Upgrade dependencies to the latest versions

Co-authored-by: japborst <japborst@gmail.com>
Co-authored-by: Gijs de Jong <berichtaangijs@gmail.com>

.github/ISSUE_TEMPLATE/feature_request.md

@@ -17,24 +17,23 @@ you'd like to be solved through Error Prone Support. -->
 
 - [ ] Support a stylistic preference.
 - [ ] Avoid a common gotcha, or potential problem.
-- [ ] Improve performance.
 
 <!--
 Here, provide a clear and concise description of the desired change.
 
 If possible, provide a simple and minimal example using the following format:
+
+  I would like to rewrite the following code:
+  ```java
+  // XXX: Write the code to match here.
+  ```
+
+  to:
+  ```java
+  // XXX: Write the desired code here.
+  ```
 -->
 
-I would like to rewrite the following code:
-```java
-// XXX: Write the code to match here.
-```
-
-to:
-```java
-// XXX: Write the desired code here.
-```
-
 ### Considerations
 
 <!--

.github/workflows/build.yaml

@@ -7,27 +7,10 @@ permissions:
   contents: read
 jobs:
   build:
+    runs-on: ubuntu-22.04
     strategy:
       matrix:
-        os: [ ubuntu-22.04 ]
-        jdk: [ 11.0.16, 17.0.4, 19 ]
-        distribution: [ temurin ]
-        experimental: [ false ]
-        include:
-          - os: macos-12
-            jdk: 17.0.4
-            distribution: temurin
-            experimental: false
-          - os: windows-2022
-            jdk: 17.0.4
-            distribution: temurin
-            experimental: false
-          - os: ubuntu-22.04
-            jdk: 20-ea
-            distribution: zulu
-            experimental: true
-    runs-on: ${{ matrix.os }}
-    continue-on-error: ${{ matrix.experimental }}
+        jdk: [ 11.0.16, 17.0.4 ]
     steps:
         # We run the build twice for each supported JDK: once against the
         # original Error Prone release, using only Error Prone checks available
@@ -37,10 +20,10 @@ jobs:
       - name: Check out code
         uses: actions/checkout@v3.1.0
       - name: Set up JDK
-        uses: actions/setup-java@v3.8.0
+        uses: actions/setup-java@v3.5.1
         with:
           java-version: ${{ matrix.jdk }}
-          distribution: ${{ matrix.distribution }}
+          distribution: temurin
           cache: maven
       - name: Display build environment details
         run: mvn --version

.github/workflows/deploy-website.yaml

@@ -3,47 +3,41 @@ on:
   pull_request:
   push:
     branches: [ master, website ]
+permissions:
+  contents: read
+  id-token: write
+  pages: write
 concurrency:
-  group: ${{ github.workflow }}-${{ github.ref }}
+  group: pages
+  cancel-in-progress: true
 jobs:
   build:
-    permissions:
-      contents: read
     runs-on: ubuntu-22.04
     steps:
       - name: Check out code
         uses: actions/checkout@v3.1.0
-      - uses: ruby/setup-ruby@v1.126.0
+      - uses: ruby/setup-ruby@v1.117.0
         with:
           working-directory: ./website
           bundler-cache: true
       - name: Configure Github Pages
-        uses: actions/configure-pages@v2.1.3
-      - name: Set up JDK
-        uses: actions/setup-java@v3.5.1
-        with:
-          java-version: 17.0.4
-          distribution: temurin
-          cache: maven
-      - name: Compile project and extract data
-        # XXX: Remove `-Dverification.{skip|warn}` and update `website/README.md`
-        # once module `docgen` has no errors.
-        run: |
-          mvn -T1C clean install -DskipTests -Dverification.warn
-          mvn -T1C clean install -DskipTests -Dverification.skip -Pdocgen
+        uses: actions/configure-pages@v2.1.1
+      # XXX: Run website/generate-docs.rb instead.
       - name: Generate documentation
         working-directory: ./website
         run: bundle exec ruby generate-docs.rb
+      - name: Validate HTML output
+        working-directory: ./website
+        # XXX: Drop `--disable_external true` once we fully adopted the
+        # "Refaster rules" terminology on our website and in the code.
+        run: bundle exec htmlproofer --disable_external true --check-external-hash false ./_site
       - name: Upload website as artifact
-        uses: actions/upload-pages-artifact@v1.0.5
+        uses: actions/upload-pages-artifact@v1.0.4
         with:
           path: ./website/_site
   deploy:
     if: github.ref == 'refs/heads/website'
     needs: build
-    permissions:
-      id-token: write
-      pages: write
     runs-on: ubuntu-22.04
     environment:
       name: github-pages
@@ -51,4 +45,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v1.2.3
+        uses: actions/deploy-pages@v1.2.1

.github/workflows/pitest-analyze-pr.yml

@@ -1,37 +0,0 @@
-# Performs mutation testing analysis on the files changed by a pull request and
-# uploads the results. The associated PR is subsequently updated by the
-# `pitest-update-pr.yml` workflow. See https://blog.pitest.org/oss-pitest-pr/
-# for details.
-name: "Mutation testing"
-on:
-  pull_request:
-permissions:
-  contents: read
-jobs:
-  analyze-pr:
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Check out code
-        uses: actions/checkout@v3.1.0
-        with:
-          fetch-depth: 2
-      - name: Set up JDK
-        uses: actions/setup-java@v3.8.0
-        with:
-          java-version: 17.0.4
-          distribution: temurin
-          cache: maven
-      - name: Run Pitest
-        # By running with features `+GIT(from[HEAD~1]), +gitci`, Pitest only
-        # analyzes lines changed in the associated pull request, as GitHub
-        # exposes the changes unique to the PR as a single commit on top of the
-        # target branch. See https://blog.pitest.org/pitest-pr-setup for
-        # details.
-        run: mvn test pitest:mutationCoverage -DargLine.xmx=2048m -Dverification.skip -Dfeatures="+GIT(from[HEAD~1]), +gitci"
-      - name: Aggregate Pitest reports
-        run: mvn pitest-git:aggregate -DkilledEmoji=":tada:" -DmutantEmoji=":zombie:" -DtrailingText="Mutation testing report by [Pitest](https://pitest.org/). Review any surviving mutants by inspecting the line comments under [_Files changed_](${{ github.event.number }}/files)."
-      - name: Upload Pitest reports as artifact
-        uses: actions/upload-artifact@v3.1.1
-        with:
-          name: pitest-reports
-          path: ./target/pit-reports-ci

.github/workflows/pitest-update-pr.yml

@@ -1,35 +0,0 @@
-# Updates a pull request based on the corresponding mutation testing analysis
-# performed by the `pitest-analyze-pr.yml` workflow. See
-# https://blog.pitest.org/oss-pitest-pr/ for details.
-name: "Mutation testing: post results"
-on:
-  workflow_run:
-    workflows: ["Mutation testing"]
-    types:
-      - completed
-permissions:
-  actions: read
-  checks: write
-  contents: read
-  pull-requests: write
-jobs:
-  update-pr:
-    if: ${{ github.event.workflow_run.conclusion == 'success' }}
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Check out code
-        uses: actions/checkout@v3.1.0
-      - name: Set up JDK
-        uses: actions/setup-java@v3.8.0
-        with:
-          java-version: 17.0.4
-          distribution: temurin
-          cache: maven
-      - name: Download Pitest analysis artifact
-        uses: dawidd6/action-download-artifact@v2.24.2
-        with:
-          workflow: ${{ github.event.workflow_run.workflow_id }}
-          name: pitest-reports
-          path: ./target/pit-reports-ci
-      - name: Update PR
-        run: mvn -DrepoToken="${{ secrets.GITHUB_TOKEN }}" pitest-github:updatePR

.mvn/maven.config

@@ -1,3 +1 @@
---batch-mode
---errors
---strict-checksums
+--batch-mode --errors --strict-checksums

.renovaterc.json

@@ -10,7 +10,7 @@
     },
     {
       "matchPackagePatterns": [
-        "^ruby\\/setup-ruby$"
+        "^com\\.palantir\\.baseline:baseline-error-prone$"
       ],
       "schedule": "* * 1 * *"
     }

LICENSE.md

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017-2023 Picnic Technologies BV
+Copyright (c) 2017-2022 Picnic Technologies BV
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -20,7 +20,6 @@ loves Error Prone: producing high-quality and consistent Java
 code_][picnic-blog-ep-post].
 
 [![Maven Central][maven-central-badge]][maven-central-search]
-[![Reproducible Builds][reproducible-builds-badge]][reproducible-builds-report]
 [![GitHub Actions][github-actions-build-badge]][github-actions-build-master]
 [![License][license-badge]][license]
 [![PRs Welcome][pr-badge]][contributing]
@@ -36,9 +35,7 @@ code_][picnic-blog-ep-post].
 ### Installation
 
 This library is built on top of [Error Prone][error-prone-orig-repo]. To use
-it, read the installation guide for Maven or Gradle below.
-
-#### Maven
+it:
 
 1. First, follow Error Prone's [installation
    guide][error-prone-installation-guide].
@@ -96,31 +93,6 @@ it, read the installation guide for Maven or Gradle below.
 Prone Support. Alternatively reference this project's `self-check` profile
 definition. -->
 
-#### Gradle
-
-1. First, follow the [installation guide]
-   [error-prone-gradle-installation-guide] of the `gradle-errorprone-plugin`.
-2. Next, edit your `build.gradle` file to add one or more Error Prone Support
-   modules:
-
-   ```groovy
-   dependencies {
-       // Error Prone itself.
-       errorprone("com.google.errorprone:error_prone_core:${errorProneVersion}")
-       // Error Prone Support's additional bug checkers.
-       errorprone("tech.picnic.error-prone-support:error-prone-contrib:${errorProneSupportVersion}")
-       // Error Prone Support's Refaster rules.
-       errorprone("tech.picnic.error-prone-support:refaster-runner:${errorProneSupportVersion}")
-   }
-
-   tasks.withType(JavaCompile).configureEach {
-       options.errorprone.disableWarningsInGeneratedCode = true
-       // Add other Error Prone flags here. See:
-       // - https://github.com/tbroyer/gradle-errorprone-plugin#configuration
-       // - https://errorprone.info/docs/flags
-   }
-   ```
-
 ### Seeing it in action
 
 Consider the following example code:
@@ -147,13 +119,16 @@ code with Maven should yield two compiler warnings:
 ```sh
 $ mvn clean install
 ...
-[INFO] Example.java:[9,34] [Refaster Rule] BigDecimalRules.BigDecimalZero: Refactoring opportunity
-    (see https://error-prone.picnic.tech/refasterrules/BigDecimalRules#BigDecimalZero)
+[INFO] -------------------------------------------------------------
+[WARNING] COMPILATION WARNING :
+[INFO] -------------------------------------------------------------
+[WARNING] Example.java:[9,34] [tech.picnic.errorprone.refasterrules.BigDecimalRules.BigDecimalZero]
   Did you mean 'return BigDecimal.ZERO;'?
-...
 [WARNING] Example.java:[13,35] [IdentityConversion] This method invocation appears redundant; remove it or suppress this warning and add a comment explaining its purpose
     (see https://error-prone.picnic.tech/bugpatterns/IdentityConversion)
   Did you mean 'return set;' or '@SuppressWarnings("IdentityConversion") public ImmutableSet<Integer> getSet() {'?
+[INFO] 2 warnings
+[INFO] -------------------------------------------------------------
 ...
 ```
 
@@ -193,7 +168,7 @@ Some other commands one may find relevant:
 
 - `mvn fmt:format` formats the code using
   [`google-java-format`][google-java-format].
-- `./run-mutation-tests.sh` runs mutation tests using [Pitest][pitest]. The
+- `./run-mutation-tests.sh` runs mutation tests using [PIT][pitest]. The
   results can be reviewed by opening the respective
   `target/pit-reports/index.html` files. For more information check the [PIT
   Maven plugin][pitest-maven].
@@ -234,7 +209,6 @@ guidelines][contributing].
 [error-prone-bugchecker]: https://github.com/google/error-prone/blob/master/check_api/src/main/java/com/google/errorprone/bugpatterns/BugChecker.java
 [error-prone-fork-jitpack]: https://jitpack.io/#PicnicSupermarket/error-prone
 [error-prone-fork-repo]: https://github.com/PicnicSupermarket/error-prone
-[error-prone-gradle-installation-guide]: https://github.com/tbroyer/gradle-errorprone-plugin
 [error-prone-installation-guide]: https://errorprone.info/docs/installation#maven
 [error-prone-orig-repo]: https://github.com/google/error-prone
 [error-prone-pull-3301]: https://github.com/google/error-prone/pull/3301
@@ -255,5 +229,3 @@ guidelines][contributing].
 [refaster]: https://errorprone.info/docs/refaster
 [refaster-rules-bigdecimal]: https://github.com/PicnicSupermarket/error-prone-support/blob/master/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/BigDecimalRules.java
 [refaster-rules]: https://github.com/PicnicSupermarket/error-prone-support/blob/master/error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/
-[reproducible-builds-badge]: https://img.shields.io/badge/Reproducible_Builds-ok-success?labelColor=1e5b96
-[reproducible-builds-report]: https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/tech/picnic/error-prone-support/error-prone-support/README.md

apply-error-prone-suggestions.sh

@@ -9,14 +9,13 @@
 set -e -u -o pipefail
 
 if [ "${#}" -gt 1 ]; then
-  echo "Usage: ${0} [PatchChecks]"
+  echo "Usage: ./$(basename "${0}") [PatchChecks]"
   exit 1
 fi
 
 patchChecks=${1:-}
 
 mvn clean test-compile fmt:format \
-  -s "$(dirname "${0}")/settings.xml" \
   -T 1.0C \
   -Perror-prone \
   -Perror-prone-fork \

cdg-pitest-licence.txt

@@ -1,7 +0,0 @@
-# Arcmutate license for Error Prone Support, requested by sending an email to
-# support@arcmutate.com.
-expires=07/11/2023
-keyVersion=1
-signature=MhZxMbnO6UovNfllM0JuVWkZyvRT3/G5o/uT0Mm36c7200VpZNVu03gTAGivnl9W5RzvZhfpIHccuQ5ctjQkrqhsFSrl4fyqPqu3y5V2fsHIdFXP/G72EGj6Kay9ndLpaEHalqE0bEwxdnHMzEYq5y3O9vUPv8MhUl57xk+rvBo\=
-packages=tech.picnic.errorprone.*
-type=OSSS

docgen/pom.xml

@@ -0,0 +1,53 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>tech.picnic.error-prone-support</groupId>
+        <artifactId>error-prone-support</artifactId>
+        <version>0.3.1-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>docgen</artifactId>
+
+    <name>Picnic :: Error Prone Support :: Docgen</name>
+    <description>Docgen.</description>
+
+    <dependencies>
+        <dependency>
+            <groupId>${groupId.error-prone}</groupId>
+            <artifactId>error_prone_annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>${groupId.error-prone}</groupId>
+            <artifactId>error_prone_check_api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>${groupId.error-prone}</groupId>
+            <artifactId>error_prone_core</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto.service</groupId>
+            <artifactId>auto-service-annotations</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.auto.value</groupId>
+            <artifactId>auto-value-annotations</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>jsr305</artifactId>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+        </dependency>
+    </dependencies>
+</project>

docgen/src/main/java/tech/picnic/errorprone/plugin/BugPatternExtractor.java

@@ -0,0 +1,26 @@
+package tech.picnic.errorprone.plugin;
+
+import com.google.common.collect.ImmutableList;
+import com.google.errorprone.BugPattern;
+import com.google.errorprone.VisitorState;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.util.TaskEvent;
+import tech.picnic.errorprone.plugin.models.BugPatternData;
+
+public final class BugPatternExtractor implements DocExtractor<BugPatternData> {
+  @Override
+  public BugPatternData extractData(ClassTree tree, TaskEvent taskEvent, VisitorState state) {
+    BugPattern annotation = taskEvent.getTypeElement().getAnnotation(BugPattern.class);
+    return BugPatternData.create(
+        taskEvent.getTypeElement().getQualifiedName().toString(),
+        taskEvent.getTypeElement().getSimpleName().toString(),
+        ImmutableList.copyOf(annotation.altNames()),
+        annotation.linkType(),
+        annotation.link(),
+        ImmutableList.copyOf(annotation.tags()),
+        annotation.summary(),
+        annotation.explanation(),
+        annotation.severity(),
+        annotation.disableable());
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/BugPatternTestsExtractor.java

@@ -0,0 +1,104 @@
+package tech.picnic.errorprone.plugin;
+
+import static com.google.errorprone.matchers.Matchers.allOf;
+import static com.google.errorprone.matchers.Matchers.hasAnnotation;
+import static com.google.errorprone.matchers.Matchers.instanceMethod;
+
+import com.google.errorprone.VisitorState;
+import com.google.errorprone.annotations.Var;
+import com.google.errorprone.matchers.Matcher;
+import com.google.errorprone.util.ASTHelpers;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.tree.ExpressionTree;
+import com.sun.source.tree.MethodInvocationTree;
+import com.sun.source.tree.MethodTree;
+import com.sun.source.util.TaskEvent;
+import com.sun.source.util.TreeScanner;
+import java.util.ArrayList;
+import java.util.List;
+import tech.picnic.errorprone.plugin.models.BugPatternReplacementTestData;
+import tech.picnic.errorprone.plugin.models.BugPatternTestData;
+
+/** XXX: Write this. */
+// XXX: Take into account `expectUnchanged()`.
+public final class BugPatternTestsExtractor implements DocExtractor<BugPatternTestData> {
+  private static final Matcher<MethodTree> JUNIT_TEST_METHOD =
+      allOf(hasAnnotation("org.junit.jupiter.api.Test"));
+
+  private static final Matcher<ExpressionTree> IDENTIFICATION_SOURCE_LINES =
+      instanceMethod()
+          .onDescendantOf("com.google.errorprone.CompilationTestHelper")
+          .named("addSourceLines");
+  private static final Matcher<ExpressionTree> REPLACEMENT_INPUT =
+      instanceMethod()
+          .onDescendantOf("com.google.errorprone.BugCheckerRefactoringTestHelper")
+          .named("addInputLines");
+  private static final Matcher<ExpressionTree> REPLACEMENT_OUTPUT =
+      instanceMethod()
+          .onDescendantOf("com.google.errorprone.BugCheckerRefactoringTestHelper.ExpectOutput")
+          .named("addOutputLines");
+
+  @Override
+  public BugPatternTestData extractData(ClassTree tree, TaskEvent taskEvent, VisitorState state) {
+    String name = tree.getSimpleName().toString().replace("Test", "");
+    ScanBugCheckerTestData scanner = new ScanBugCheckerTestData(state);
+
+    tree.getMembers().stream()
+        .filter(MethodTree.class::isInstance)
+        .map(MethodTree.class::cast)
+        .filter(m -> JUNIT_TEST_METHOD.matches(m, state))
+        .forEach(m -> scanner.scan(m, null));
+
+    return BugPatternTestData.create(
+        name, scanner.getIdentificationTests(), scanner.getReplacementTests());
+  }
+
+  private static final class ScanBugCheckerTestData extends TreeScanner<Void, Void> {
+    private final VisitorState state;
+    private final List<String> identificationTests = new ArrayList<>();
+    private final List<BugPatternReplacementTestData> replacementTests = new ArrayList<>();
+
+    // XXX: Using this output field is a bit hacky. Come up with a better solution.
+    @Var private String output;
+
+    ScanBugCheckerTestData(VisitorState state) {
+      this.state = state;
+    }
+
+    public List<String> getIdentificationTests() {
+      return identificationTests;
+    }
+
+    public List<BugPatternReplacementTestData> getReplacementTests() {
+      return replacementTests;
+    }
+
+    @Override
+    public Void visitMethodInvocation(MethodInvocationTree node, Void unused) {
+      if (IDENTIFICATION_SOURCE_LINES.matches(node, state)) {
+        identificationTests.add(getSourceLines(node));
+      } else if (REPLACEMENT_INPUT.matches(node, state)) {
+        replacementTests.add(BugPatternReplacementTestData.create(getSourceLines(node), output));
+      } else if (REPLACEMENT_OUTPUT.matches(node, state)) {
+        output = getSourceLines(node);
+      }
+      return super.visitMethodInvocation(node, unused);
+    }
+
+    private static String getSourceLines(MethodInvocationTree tree) {
+      List<? extends ExpressionTree> sourceLines =
+          tree.getArguments().subList(1, tree.getArguments().size());
+      StringBuilder source = new StringBuilder();
+
+      for (ExpressionTree sourceLine : sourceLines) {
+        Object value = ASTHelpers.constValue(sourceLine);
+        if (value == null) {
+          return "";
+        }
+        source.append(value).append('\n');
+      }
+
+      return source.toString();
+    }
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/DocExtractor.java

@@ -0,0 +1,9 @@
+package tech.picnic.errorprone.plugin;
+
+import com.google.errorprone.VisitorState;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.util.TaskEvent;
+
+public interface DocExtractor<T> {
+  T extractData(ClassTree tree, TaskEvent taskEvent, VisitorState state);
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/DocType.java

@@ -0,0 +1,25 @@
+package tech.picnic.errorprone.plugin;
+
+public enum DocType {
+  BUG_PATTERN("bug-pattern", new BugPatternExtractor()),
+  BUG_PATTERN_TEST("bug-pattern-test", new BugPatternTestsExtractor()),
+  //  REFASTER("refaster", new RefasterExtractor()),
+  REFASTER_TEMPLATE_TEST_INPUT("refaster-test-input", new RefasterTestExtractor()),
+  REFASTER_TEMPLATE_TEST_OUTPUT("refaster-test-output", new RefasterTestExtractor());
+
+  private final String outputFileNamePrefix;
+  private final DocExtractor<?> docExtractor;
+
+  DocType(String outputFileNamePrefix, DocExtractor<?> docExtractor) {
+    this.outputFileNamePrefix = outputFileNamePrefix;
+    this.docExtractor = docExtractor;
+  }
+
+  public String getOutputFileNamePrefix() {
+    return outputFileNamePrefix;
+  }
+
+  public DocExtractor<?> getDocExtractor() {
+    return docExtractor;
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/Docgen.java

@@ -0,0 +1,21 @@
+package tech.picnic.errorprone.plugin;
+
+import com.google.auto.service.AutoService;
+import com.sun.source.util.JavacTask;
+import com.sun.source.util.Plugin;
+import com.sun.tools.javac.api.BasicJavacTask;
+
+/** XXX: Write. */
+@AutoService(Plugin.class)
+public final class Docgen implements Plugin {
+  @Override
+  public String getName() {
+    return getClass().getSimpleName();
+  }
+
+  @Override
+  public void init(JavacTask javacTask, String... args) {
+    javacTask.addTaskListener(
+        new DocgenTaskListener(((BasicJavacTask) javacTask).getContext(), args[0]));
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/DocgenTaskListener.java

@@ -0,0 +1,123 @@
+package tech.picnic.errorprone.plugin;
+
+import static tech.picnic.errorprone.plugin.DocType.BUG_PATTERN;
+import static tech.picnic.errorprone.plugin.DocType.BUG_PATTERN_TEST;
+import static tech.picnic.errorprone.plugin.DocType.REFASTER_TEMPLATE_TEST_INPUT;
+import static tech.picnic.errorprone.plugin.DocType.REFASTER_TEMPLATE_TEST_OUTPUT;
+
+import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
+import com.fasterxml.jackson.annotation.PropertyAccessor;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationFeature;
+import com.google.errorprone.BugPattern;
+import com.google.errorprone.VisitorState;
+import com.google.errorprone.util.ASTHelpers;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.tree.VariableTree;
+import com.sun.source.util.TaskEvent;
+import com.sun.source.util.TaskListener;
+import com.sun.tools.javac.api.JavacTrees;
+import com.sun.tools.javac.util.Context;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Optional;
+import javax.tools.JavaFileObject;
+
+/** XXX: Write this. */
+final class DocgenTaskListener implements TaskListener {
+  private final Context context;
+
+  private final String basePath;
+
+  private final VisitorState state;
+
+  private final ObjectMapper mapper =
+      new ObjectMapper()
+          .setVisibility(PropertyAccessor.FIELD, Visibility.ANY)
+          .configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false)
+          .configure(JsonGenerator.Feature.AUTO_CLOSE_TARGET, false);
+
+  DocgenTaskListener(Context context, String path) {
+    this.context = context;
+    this.basePath = path.substring(path.indexOf('=') + 1) + "/docs";
+    this.state = VisitorState.createForUtilityPurposes(context);
+
+    // XXX: Move this somewhere else?
+    try {
+      Files.createDirectories(Paths.get(basePath));
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  @Override
+  @SuppressWarnings("SystemOut")
+  public void finished(TaskEvent taskEvent) {
+    ClassTree tree = JavacTrees.instance(context).getTree(taskEvent.getTypeElement());
+    JavaFileObject sourceFile = taskEvent.getSourceFile();
+    if (tree == null || sourceFile == null || taskEvent.getKind() != TaskEvent.Kind.ANALYZE) {
+      return;
+    }
+
+    getDocType(tree, sourceFile)
+        .ifPresent(
+            docType ->
+                writeToFile(
+                    docType.getDocExtractor().extractData(tree, taskEvent, state),
+                    docType.getOutputFileNamePrefix(),
+                    getSimpleClassName(sourceFile.getName())));
+  }
+
+  private static Optional<DocType> getDocType(ClassTree tree, JavaFileObject sourceFile) {
+    if (isBugPattern(tree)) {
+      return Optional.of(BUG_PATTERN);
+    } else if (isBugPatternTest(tree)) {
+      return Optional.of(BUG_PATTERN_TEST);
+    } else if (sourceFile.getName().contains("TestInput")) {
+      return Optional.of(REFASTER_TEMPLATE_TEST_INPUT);
+    } else if (sourceFile.getName().contains("TestOutput")) {
+      return Optional.of(REFASTER_TEMPLATE_TEST_OUTPUT);
+    }
+    return Optional.empty();
+  }
+
+  private <T> void writeToFile(T data, String fileName, String name) {
+    File file = new File(basePath + "/" + fileName + "-" + name + ".json");
+    // XXX: Use Path instead of File.
+
+    try (FileWriter fileWriter = new FileWriter(file, true)) {
+      mapper.writeValue(fileWriter, data);
+      fileWriter.write("\n");
+    } catch (IOException e) {
+      e.printStackTrace();
+    }
+  }
+
+  private static boolean isBugPattern(ClassTree tree) {
+    return ASTHelpers.hasDirectAnnotationWithSimpleName(tree, BugPattern.class.getSimpleName());
+  }
+
+  private static boolean isBugPatternTest(ClassTree tree) {
+    return tree.getSimpleName().toString().endsWith("Test")
+        // XXX: Instead, omit files from the util directory
+        && !tree.getSimpleName().toString().equals("MethodMatcherFactoryTest")
+        && tree.getMembers().stream()
+            .filter(VariableTree.class::isInstance)
+            .map(VariableTree.class::cast)
+            .map(vt -> vt.getType().toString())
+            .anyMatch(
+                vt ->
+                    vt.equals("BugCheckerRefactoringTestHelper")
+                        || vt.equals("CompilationTestHelper"));
+  }
+
+  private static String getSimpleClassName(String path) {
+    int index = path.lastIndexOf('/');
+    String fileName = path.substring(index + 1);
+    return fileName.replace(".java", "");
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/RefasterTestExtractor.java

@@ -0,0 +1,35 @@
+package tech.picnic.errorprone.plugin;
+
+import static com.google.common.collect.ImmutableList.toImmutableList;
+
+import com.google.common.collect.ImmutableList;
+import com.google.errorprone.VisitorState;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.tree.MethodTree;
+import com.sun.source.util.TaskEvent;
+import tech.picnic.errorprone.plugin.models.RefasterTemplateCollectionTestData;
+import tech.picnic.errorprone.plugin.models.RefasterTemplateTestData;
+
+public final class RefasterTestExtractor
+    implements DocExtractor<RefasterTemplateCollectionTestData> {
+  @Override
+  public RefasterTemplateCollectionTestData extractData(
+      ClassTree tree, TaskEvent taskEvent, VisitorState state) {
+    String templateCollectionName = tree.getSimpleName().toString().replace("Test", "");
+    boolean isInput = taskEvent.getSourceFile().getName().contains("Input");
+
+    ImmutableList<RefasterTemplateTestData> templateTests =
+        tree.getMembers().stream()
+            .filter(MethodTree.class::isInstance)
+            .map(MethodTree.class::cast)
+            .filter(m -> m.getName().toString().startsWith("test"))
+            .map(
+                m ->
+                    RefasterTemplateTestData.create(
+                        m.getName().toString().replace("test", ""), m.toString()))
+            .collect(toImmutableList());
+
+    return RefasterTemplateCollectionTestData.create(
+        templateCollectionName, isInput, templateTests);
+  }
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/BugPatternData.java

@@ -0,0 +1,55 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableList;
+import com.google.errorprone.BugPattern.LinkType;
+import com.google.errorprone.BugPattern.SeverityLevel;
+
+/** XXX: Write. */
+// XXX: What about `SuppressionAnnotations` and `DocumentSuppression`?
+@AutoValue
+public abstract class BugPatternData {
+  public static BugPatternData create(
+      String fullyQualifiedName,
+      String name,
+      ImmutableList<String> altNames,
+      LinkType linkType,
+      String link,
+      ImmutableList<String> tags,
+      String summary,
+      String explanation,
+      SeverityLevel severityLevel,
+      boolean disableable) {
+    return new AutoValue_BugPatternData(
+        fullyQualifiedName,
+        name,
+        altNames,
+        linkType,
+        link,
+        tags,
+        summary,
+        explanation,
+        severityLevel,
+        disableable);
+  }
+
+  abstract String fullyQualifiedName();
+
+  abstract String name();
+
+  abstract ImmutableList<String> altNames();
+
+  abstract LinkType linkType();
+
+  abstract String link();
+
+  abstract ImmutableList<String> tags();
+
+  abstract String summary();
+
+  abstract String explanation();
+
+  abstract SeverityLevel severityLevel();
+
+  abstract boolean disableable();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/BugPatternReplacementTestData.java

@@ -0,0 +1,17 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import javax.annotation.Nullable;
+
+@AutoValue
+public abstract class BugPatternReplacementTestData {
+  public static BugPatternReplacementTestData create(String inputLines, String outputLines) {
+    return new AutoValue_BugPatternReplacementTestData(inputLines, outputLines);
+  }
+
+  @Nullable
+  abstract String inputLines();
+
+  @Nullable
+  abstract String outputLines();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/BugPatternTestData.java

@@ -0,0 +1,23 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import java.util.List;
+import javax.annotation.Nullable;
+
+@AutoValue
+public abstract class BugPatternTestData {
+  public static BugPatternTestData create(
+      String name,
+      List<String> identificationTests,
+      List<BugPatternReplacementTestData> replacementTests) {
+    return new AutoValue_BugPatternTestData(name, identificationTests, replacementTests);
+  }
+
+  abstract String name();
+
+  @Nullable
+  abstract List<String> identificationTests();
+
+  @Nullable
+  abstract List<BugPatternReplacementTestData> replacementTests();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/RefasterTemplateCollectionData.java

@@ -0,0 +1,24 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import java.util.List;
+
+/**
+ * Object containing all data related to a Refaster template collection. This is solely used for
+ * serialization.
+ */
+@AutoValue
+public abstract class RefasterTemplateCollectionData {
+  public static RefasterTemplateCollectionData create(
+      String name, String description, String link, List<RefasterTemplateData> templates) {
+    return new AutoValue_RefasterTemplateCollectionData(name, description, link, templates);
+  }
+
+  abstract String name();
+
+  abstract String description();
+
+  abstract String link();
+
+  abstract List<RefasterTemplateData> templates();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/RefasterTemplateCollectionTestData.java

@@ -0,0 +1,19 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import java.util.List;
+
+@AutoValue
+public abstract class RefasterTemplateCollectionTestData {
+  public static RefasterTemplateCollectionTestData create(
+      String templateCollection, boolean isInput, List<RefasterTemplateTestData> templatesTests) {
+    return new AutoValue_RefasterTemplateCollectionTestData(
+        templateCollection, isInput, templatesTests);
+  }
+
+  abstract String templateCollection();
+
+  abstract boolean isInput();
+
+  abstract List<RefasterTemplateTestData> templateTests();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/RefasterTemplateData.java

@@ -0,0 +1,20 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+import com.google.errorprone.BugPattern.SeverityLevel;
+
+@AutoValue
+public abstract class RefasterTemplateData {
+  public static RefasterTemplateData create(
+      String name, String description, String link, SeverityLevel severityLevel) {
+    return new AutoValue_RefasterTemplateData(name, description, link, severityLevel);
+  }
+
+  abstract String name();
+
+  abstract String description();
+
+  abstract String link();
+
+  abstract SeverityLevel severityLevel();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/models/RefasterTemplateTestData.java

@@ -0,0 +1,14 @@
+package tech.picnic.errorprone.plugin.models;
+
+import com.google.auto.value.AutoValue;
+
+@AutoValue
+public abstract class RefasterTemplateTestData {
+  public static RefasterTemplateTestData create(String templateName, String templateTestContent) {
+    return new AutoValue_RefasterTemplateTestData(templateName, templateTestContent);
+  }
+
+  abstract String templateName();
+
+  abstract String templateTestContent();
+}

docgen/src/main/java/tech/picnic/errorprone/plugin/package-info.java

@@ -0,0 +1,4 @@
+/** A Java compiler plugin that XXX: fill in. */
+@com.google.errorprone.annotations.CheckReturnValue
+@javax.annotation.ParametersAreNonnullByDefault
+package tech.picnic.errorprone.plugin;

documentation-support/pom.xml

@@ -1,87 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-
-    <parent>
-        <groupId>tech.picnic.error-prone-support</groupId>
-        <artifactId>error-prone-support</artifactId>
-        <version>0.8.1-SNAPSHOT</version>
-    </parent>
-
-    <artifactId>documentation-support</artifactId>
-
-    <name>Picnic :: Error Prone Support :: Documentation Support</name>
-    <description>Data extraction support for the purpose of documentation generation.</description>
-
-    <dependencies>
-        <dependency>
-            <groupId>${groupId.error-prone}</groupId>
-            <artifactId>error_prone_annotation</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>${groupId.error-prone}</groupId>
-            <artifactId>error_prone_annotations</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>${groupId.error-prone}</groupId>
-            <artifactId>error_prone_check_api</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>${groupId.error-prone}</groupId>
-            <artifactId>error_prone_test_helpers</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>com.fasterxml.jackson.core</groupId>
-            <artifactId>jackson-annotations</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>com.fasterxml.jackson.core</groupId>
-            <artifactId>jackson-databind</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>com.google.auto</groupId>
-            <artifactId>auto-common</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>com.google.auto.service</groupId>
-            <artifactId>auto-service-annotations</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>com.google.auto.value</groupId>
-            <artifactId>auto-value-annotations</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.assertj</groupId>
-            <artifactId>assertj-core</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.jspecify</groupId>
-            <artifactId>jspecify</artifactId>
-            <scope>provided</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-engine</artifactId>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-params</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
-</project>

documentation-support/src/main/java/tech/picnic/errorprone/documentation/BugPatternExtractor.java

@@ -1,105 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.common.base.Verify.verify;
-import static com.google.common.collect.ImmutableList.toImmutableList;
-import static java.util.Objects.requireNonNull;
-
-import com.google.auto.common.AnnotationMirrors;
-import com.google.auto.value.AutoValue;
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.BugPattern.SeverityLevel;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.annotations.Immutable;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.AnnotationTree;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.util.TaskEvent;
-import com.sun.tools.javac.code.Attribute;
-import com.sun.tools.javac.code.Symbol.ClassSymbol;
-import com.sun.tools.javac.util.Context;
-import javax.lang.model.element.AnnotationValue;
-import tech.picnic.errorprone.documentation.BugPatternExtractor.BugPatternDocumentation;
-
-/**
- * An {@link Extractor} that describes how to extract data from a {@code @BugPattern} annotation.
- */
-@Immutable
-final class BugPatternExtractor implements Extractor<BugPatternDocumentation> {
-  @Override
-  public BugPatternDocumentation extract(ClassTree tree, Context context, TaskEvent taskEvent) {
-    ClassSymbol symbol = ASTHelpers.getSymbol(tree);
-    BugPattern annotation = symbol.getAnnotation(BugPattern.class);
-    requireNonNull(annotation, "BugPattern annotation must be present");
-
-    return new AutoValue_BugPatternExtractor_BugPatternDocumentation(
-        symbol.getQualifiedName().toString(),
-        annotation.name().isEmpty() ? tree.getSimpleName().toString() : annotation.name(),
-        ImmutableList.copyOf(annotation.altNames()),
-        annotation.link(),
-        ImmutableList.copyOf(annotation.tags()),
-        annotation.summary(),
-        annotation.explanation(),
-        annotation.severity(),
-        annotation.disableable(),
-        annotation.documentSuppression() ? getSuppressionAnnotations(tree) : ImmutableList.of());
-  }
-
-  @Override
-  public boolean canExtract(ClassTree tree, VisitorState state) {
-    return ASTHelpers.hasDirectAnnotationWithSimpleName(tree, BugPattern.class.getSimpleName());
-  }
-
-  /**
-   * Returns the fully-qualified class names of suppression annotations specified by the {@link
-   * BugPattern} annotation located on the given tree.
-   *
-   * @implNote This method cannot simply invoke {@link BugPattern#suppressionAnnotations()}, as that
-   *     will yield an "Attempt to access Class objects for TypeMirrors" exception.
-   */
-  private static ImmutableList<String> getSuppressionAnnotations(ClassTree tree) {
-    AnnotationTree annotationTree =
-        ASTHelpers.getAnnotationWithSimpleName(
-            ASTHelpers.getAnnotations(tree), BugPattern.class.getSimpleName());
-    requireNonNull(annotationTree, "BugPattern annotation must be present");
-
-    Attribute.Array types =
-        doCast(
-            AnnotationMirrors.getAnnotationValue(
-                ASTHelpers.getAnnotationMirror(annotationTree), "suppressionAnnotations"),
-            Attribute.Array.class);
-
-    return types.getValue().stream()
-        .map(v -> doCast(v, Attribute.Class.class).classType.toString())
-        .collect(toImmutableList());
-  }
-
-  @SuppressWarnings("unchecked")
-  private static <T extends AnnotationValue> T doCast(AnnotationValue value, Class<T> target) {
-    verify(target.isInstance(value), "Value '%s' is not of type '%s'", value, target);
-    return (T) value;
-  }
-
-  @AutoValue
-  abstract static class BugPatternDocumentation {
-    abstract String fullyQualifiedName();
-
-    abstract String name();
-
-    abstract ImmutableList<String> altNames();
-
-    abstract String link();
-
-    abstract ImmutableList<String> tags();
-
-    abstract String summary();
-
-    abstract String explanation();
-
-    abstract SeverityLevel severityLevel();
-
-    abstract boolean canDisable();
-
-    abstract ImmutableList<String> suppressionAnnotations();
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/BugPatternTestExtractor.java

@@ -1,180 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.errorprone.matchers.Matchers.hasAnnotation;
-import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-
-import com.google.auto.value.AutoValue;
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.annotations.Immutable;
-import com.google.errorprone.annotations.Var;
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.MemberSelectTree;
-import com.sun.source.tree.MethodInvocationTree;
-import com.sun.source.tree.MethodTree;
-import com.sun.source.util.TaskEvent;
-import com.sun.source.util.TreeScanner;
-import com.sun.tools.javac.util.Context;
-import java.util.ArrayList;
-import java.util.List;
-import org.jspecify.annotations.Nullable;
-import tech.picnic.errorprone.documentation.BugPatternTestExtractor.BugPatternTestDocumentation;
-
-/**
- * An {@link Extractor} that describes how to extract data from a test that tests a {@code
- * BugChecker}.
- */
-@Immutable
-final class BugPatternTestExtractor implements Extractor<BugPatternTestDocumentation> {
-  private static final Matcher<MethodTree> JUNIT_TEST_METHOD =
-      hasAnnotation("org.junit.jupiter.api.Test");
-
-  // XXX: Improve support for correctly extracting multiple sources from a single
-  // `{BugCheckerRefactoring,Compilation}TestHelper` test.
-  @Override
-  public BugPatternTestDocumentation extract(ClassTree tree, Context context, TaskEvent event) {
-    VisitorState state = VisitorState.createForUtilityPurposes(context);
-    CollectBugPatternTests scanner = new CollectBugPatternTests(state);
-
-    tree.getMembers().stream()
-        .filter(MethodTree.class::isInstance)
-        .map(MethodTree.class::cast)
-        .filter(m -> JUNIT_TEST_METHOD.matches(m, state))
-        .forEach(m -> scanner.scan(m, null));
-
-    String className = tree.getSimpleName().toString();
-    return new AutoValue_BugPatternTestExtractor_BugPatternTestDocumentation(
-        className.substring(0, className.lastIndexOf("Test")),
-        scanner.getIdentificationTests(),
-        scanner.getReplacementTests());
-  }
-
-  @Override
-  public boolean canExtract(ClassTree tree, VisitorState state) {
-    String className = tree.getSimpleName().toString();
-    if (!className.endsWith("Test")) {
-      return false;
-    }
-
-    ScanBugPatternTest scanBugPatternTest = new ScanBugPatternTest();
-    scanBugPatternTest.scan(tree, state);
-
-    String bugPatternName = className.substring(0, className.lastIndexOf("Test"));
-    return scanBugPatternTest.hasTestUsingClassInstance(bugPatternName);
-  }
-
-  private static final class ScanBugPatternTest extends TreeScanner<@Nullable Void, VisitorState> {
-    private static final Matcher<ExpressionTree> BUG_PATTERN_TEST_METHOD =
-        staticMethod()
-            .onDescendantOfAny(
-                "com.google.errorprone.CompilationTestHelper",
-                "com.google.errorprone.BugCheckerRefactoringTestHelper")
-            .named("newInstance");
-
-    private final List<String> encounteredClasses = new ArrayList<>();
-
-    boolean hasTestUsingClassInstance(String clazz) {
-      return encounteredClasses.contains(clazz);
-    }
-
-    @Override
-    public @Nullable Void visitMethodInvocation(MethodInvocationTree node, VisitorState state) {
-      if (BUG_PATTERN_TEST_METHOD.matches(node, state)) {
-        MemberSelectTree firstArgumentTree = (MemberSelectTree) node.getArguments().get(0);
-        encounteredClasses.add(firstArgumentTree.getExpression().toString());
-      }
-      return super.visitMethodInvocation(node, state);
-    }
-  }
-
-  private static final class CollectBugPatternTests
-      extends TreeScanner<@Nullable Void, @Nullable Void> {
-    private static final Matcher<ExpressionTree> IDENTIFICATION_SOURCE_LINES =
-        instanceMethod()
-            .onDescendantOf("com.google.errorprone.CompilationTestHelper")
-            .named("addSourceLines");
-    private static final Matcher<ExpressionTree> REPLACEMENT_INPUT =
-        instanceMethod()
-            .onDescendantOf("com.google.errorprone.BugCheckerRefactoringTestHelper")
-            .named("addInputLines");
-    private static final Matcher<ExpressionTree> REPLACEMENT_OUTPUT =
-        instanceMethod()
-            .onDescendantOf("com.google.errorprone.BugCheckerRefactoringTestHelper.ExpectOutput")
-            .named("addOutputLines");
-
-    private final VisitorState state;
-    private final List<String> identificationTests = new ArrayList<>();
-    private final List<BugPatternReplacementTestDocumentation> replacementTests = new ArrayList<>();
-
-    @Var private String replacementOutputLines = "";
-
-    CollectBugPatternTests(VisitorState state) {
-      this.state = state;
-    }
-
-    public ImmutableList<String> getIdentificationTests() {
-      return ImmutableList.copyOf(identificationTests);
-    }
-
-    public ImmutableList<BugPatternReplacementTestDocumentation> getReplacementTests() {
-      return ImmutableList.copyOf(replacementTests);
-    }
-
-    @Override
-    public @Nullable Void visitMethodInvocation(MethodInvocationTree node, @Nullable Void unused) {
-      if (IDENTIFICATION_SOURCE_LINES.matches(node, state)) {
-        identificationTests.add(getSourceLines(node));
-      } else if (REPLACEMENT_INPUT.matches(node, state)) {
-        /* The visitor starts with `addOutputLines` and in the next visit it will go over the `addInputLines`. */
-        replacementTests.add(
-            BugPatternReplacementTestDocumentation.create(
-                getSourceLines(node), replacementOutputLines));
-      } else if (REPLACEMENT_OUTPUT.matches(node, state)) {
-        replacementOutputLines = getSourceLines(node);
-      }
-      return super.visitMethodInvocation(node, unused);
-    }
-
-    // XXX: Duplicate from `ErrorProneTestSourceFormat`, should we move this to `SourceCode` util?
-    private static String getSourceLines(MethodInvocationTree tree) {
-      List<? extends ExpressionTree> sourceLines =
-          tree.getArguments().subList(1, tree.getArguments().size());
-      StringBuilder source = new StringBuilder();
-
-      for (ExpressionTree sourceLine : sourceLines) {
-        Object value = ASTHelpers.constValue(sourceLine);
-        if (value == null) {
-          return "";
-        }
-        source.append(value).append('\n');
-      }
-
-      return source.toString();
-    }
-  }
-
-  @AutoValue
-  abstract static class BugPatternTestDocumentation {
-    abstract String name();
-
-    abstract ImmutableList<String> identificationTests();
-
-    abstract ImmutableList<BugPatternReplacementTestDocumentation> replacementTests();
-  }
-
-  @AutoValue
-  abstract static class BugPatternReplacementTestDocumentation {
-    static BugPatternReplacementTestDocumentation create(String sourceLines, String outputLines) {
-      return new AutoValue_BugPatternTestExtractor_BugPatternReplacementTestDocumentation(
-          sourceLines, outputLines);
-    }
-
-    abstract String inputLines();
-
-    abstract String outputLines();
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/DocumentationGenerator.java

@@ -1,56 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.common.base.Preconditions.checkArgument;
-
-import com.google.auto.service.AutoService;
-import com.google.common.annotations.VisibleForTesting;
-import com.sun.source.util.JavacTask;
-import com.sun.source.util.Plugin;
-import com.sun.tools.javac.api.BasicJavacTask;
-import java.nio.file.InvalidPathException;
-import java.nio.file.Path;
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
-
-/**
- * A compiler {@link Plugin} that analyzes and extracts relevant information for documentation
- * purposes from processed files.
- */
-// XXX: Find a better name for this class; it doesn't generate documentation per se.
-@AutoService(Plugin.class)
-public final class DocumentationGenerator implements Plugin {
-  @VisibleForTesting static final String OUTPUT_DIRECTORY_FLAG = "-XoutputDirectory";
-  private static final Pattern OUTPUT_DIRECTORY_FLAG_PATTERN =
-      Pattern.compile(Pattern.quote(OUTPUT_DIRECTORY_FLAG) + "=(.*)");
-
-  /** Instantiates a new {@link DocumentationGenerator} instance. */
-  public DocumentationGenerator() {}
-
-  @Override
-  public String getName() {
-    return getClass().getSimpleName();
-  }
-
-  @Override
-  public void init(JavacTask javacTask, String... args) {
-    checkArgument(args.length == 1, "Precisely one path must be provided");
-
-    javacTask.addTaskListener(
-        new DocumentationGeneratorTaskListener(
-            ((BasicJavacTask) javacTask).getContext(), getOutputPath(args[0])));
-  }
-
-  @VisibleForTesting
-  static Path getOutputPath(String pathArg) {
-    Matcher matcher = OUTPUT_DIRECTORY_FLAG_PATTERN.matcher(pathArg);
-    checkArgument(
-        matcher.matches(), "'%s' must be of the form '%s=<value>'", pathArg, OUTPUT_DIRECTORY_FLAG);
-
-    String path = matcher.group(1);
-    try {
-      return Path.of(path);
-    } catch (InvalidPathException e) {
-      throw new IllegalArgumentException(String.format("Invalid path '%s'", path), e);
-    }
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/DocumentationGeneratorTaskListener.java

@@ -1,92 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static java.nio.charset.StandardCharsets.UTF_8;
-
-import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
-import com.fasterxml.jackson.annotation.PropertyAccessor;
-import com.fasterxml.jackson.databind.ObjectMapper;
-import com.google.errorprone.VisitorState;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.util.TaskEvent;
-import com.sun.source.util.TaskEvent.Kind;
-import com.sun.source.util.TaskListener;
-import com.sun.tools.javac.api.JavacTrees;
-import com.sun.tools.javac.util.Context;
-import java.io.File;
-import java.io.FileWriter;
-import java.io.IOException;
-import java.io.UncheckedIOException;
-import java.net.URI;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import javax.tools.JavaFileObject;
-
-/**
- * A {@link TaskListener} that identifies and extracts relevant content for documentation generation
- * and writes it to disk.
- */
-// XXX: Find a better name for this class; it doesn't generate documentation per se.
-final class DocumentationGeneratorTaskListener implements TaskListener {
-  private static final ObjectMapper OBJECT_MAPPER =
-      new ObjectMapper().setVisibility(PropertyAccessor.FIELD, Visibility.ANY);
-
-  private final Context context;
-  private final Path docsPath;
-
-  DocumentationGeneratorTaskListener(Context context, Path path) {
-    this.context = context;
-    this.docsPath = path;
-  }
-
-  @Override
-  public void started(TaskEvent taskEvent) {
-    if (taskEvent.getKind() == Kind.ANALYZE) {
-      createDocsDirectory();
-    }
-  }
-
-  @Override
-  public void finished(TaskEvent taskEvent) {
-    if (taskEvent.getKind() != Kind.ANALYZE) {
-      return;
-    }
-
-    ClassTree classTree = JavacTrees.instance(context).getTree(taskEvent.getTypeElement());
-    JavaFileObject sourceFile = taskEvent.getSourceFile();
-    if (classTree == null || sourceFile == null) {
-      return;
-    }
-
-    ExtractorType.findMatchingType(classTree, VisitorState.createForUtilityPurposes(context))
-        .ifPresent(
-            extractorType ->
-                writeToFile(
-                    extractorType.getIdentifier(),
-                    getSimpleClassName(sourceFile.toUri()),
-                    extractorType.getExtractor().extract(classTree, context, taskEvent)));
-  }
-
-  private void createDocsDirectory() {
-    try {
-      Files.createDirectories(docsPath);
-    } catch (IOException e) {
-      throw new IllegalStateException(
-          String.format("Error while creating directory with path '%s'", docsPath), e);
-    }
-  }
-
-  private <T> void writeToFile(String identifier, String className, T data) {
-    File file = docsPath.resolve(String.format("%s-%s.json", identifier, className)).toFile();
-
-    try (FileWriter fileWriter = new FileWriter(file, UTF_8)) {
-      OBJECT_MAPPER.writeValue(fileWriter, data);
-    } catch (IOException e) {
-      throw new UncheckedIOException(String.format("Cannot write to file '%s'", file.getPath()), e);
-    }
-  }
-
-  private static String getSimpleClassName(URI path) {
-    return Paths.get(path).getFileName().toString().replace(".java", "");
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/Extractor.java

@@ -1,38 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.annotations.Immutable;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.util.TaskEvent;
-import com.sun.tools.javac.util.Context;
-
-/**
- * Interface implemented by classes that define how to extract data of some type {@link T} from a
- * given {@link ClassTree}.
- *
- * @param <T> The type of data that is extracted.
- */
-@Immutable
-interface Extractor<T> {
-  /**
-   * Extracts and returns an instance of {@link T} using the provided arguments.
-   *
-   * @param tree      The {@link ClassTree} to analyze and from which to extract instances of {@link T}.
-   * @param context   The {@link Context} in which the current compilation takes place.
-   * @param taskEvent The {@link TaskEvent} in which the current compilation takes place.
-   * @return A non-null instance of {@link T}.
-   */
-  // XXX: Drop `Context` parameter unless used.
-  T extract(ClassTree tree, Context context, TaskEvent taskEvent);
-
-  /**
-   * Tells whether this {@link Extractor} can extract documentation content from the given {@link
-   * ClassTree}.
-   *
-   * @param tree The {@link ClassTree} of interest.
-   * @param state A {@link VisitorState} describes the context in which the given {@link ClassTree}
-   *     is found.
-   * @return {@code true} iff data extraction is supported.
-   */
-  boolean canExtract(ClassTree tree, VisitorState state);
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/ExtractorType.java

@@ -1,40 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.Sets;
-import com.google.errorprone.VisitorState;
-import com.sun.source.tree.ClassTree;
-import java.util.EnumSet;
-import java.util.Optional;
-
-/** An enumeration of {@link Extractor} types. */
-enum ExtractorType {
-  BUG_PATTERN("bugpattern", new BugPatternExtractor()),
-  BUG_PATTERN_TEST("bugpattern-test", new BugPatternTestExtractor()),
-  //  REFASTER("refaster", new RefasterExtractor()),
-  REFASTER_TEMPLATE_TEST_INPUT("refaster-test-input", new RefasterTestExtractor()),
-  REFASTER_TEMPLATE_TEST_OUTPUT("refaster-test-output", new RefasterTestExtractor());
-
-  private static final ImmutableSet<ExtractorType> TYPES =
-      Sets.immutableEnumSet(EnumSet.allOf(ExtractorType.class));
-
-  private final String identifier;
-  private final Extractor<?> extractor;
-
-  ExtractorType(String identifier, Extractor<?> extractor) {
-    this.identifier = identifier;
-    this.extractor = extractor;
-  }
-
-  String getIdentifier() {
-    return identifier;
-  }
-
-  Extractor<?> getExtractor() {
-    return extractor;
-  }
-
-  static Optional<ExtractorType> findMatchingType(ClassTree tree, VisitorState state) {
-    return TYPES.stream().filter(type -> type.getExtractor().canExtract(tree, state)).findFirst();
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/RefasterTestExtractor.java

@@ -1,66 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.common.collect.ImmutableList.toImmutableList;
-
-import com.google.auto.value.AutoValue;
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.VisitorState;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.tree.MethodTree;
-import com.sun.source.util.TaskEvent;
-import com.sun.source.util.TreePath;
-import com.sun.tools.javac.util.Context;
-import java.util.List;
-
-public final class RefasterTestExtractor
-    implements Extractor<RefasterTestExtractor.RefasterTemplateCollectionTestData> {
-  @Override
-  public RefasterTemplateCollectionTestData extract(
-      ClassTree tree, Context context, TaskEvent taskEvent) {
-    String templateCollectionName = tree.getSimpleName().toString().replace("Test", "");
-    boolean isInput = taskEvent.getSourceFile().getName().contains("Input");
-    VisitorState stateWithPath =
-        VisitorState.createForUtilityPurposes(context)
-            .withPath(TreePath.getPath(taskEvent.getCompilationUnit(), tree));
-
-    ImmutableList<RefasterTemplateTestData> templateTests =
-        tree.getMembers().stream()
-            .filter(MethodTree.class::isInstance)
-            .map(MethodTree.class::cast)
-            .filter(m -> m.getName().toString().startsWith("test"))
-            .map(
-                m -> {
-                  String src = stateWithPath.getSourceForNode(tree);
-                  return new AutoValue_RefasterTestExtractor_RefasterTemplateTestData(
-                      m.getName().toString().replace("test", ""),
-                      src != null ? src : tree.toString());
-                })
-            .collect(toImmutableList());
-
-    return new AutoValue_RefasterTestExtractor_RefasterTemplateCollectionTestData(
-        templateCollectionName, isInput, templateTests);
-  }
-
-  @Override
-  public boolean canExtract(ClassTree tree, VisitorState state) {
-    String className = tree.getSimpleName().toString();
-    return className.endsWith("TestInput") || className.endsWith("TestOutput");
-  }
-
-  @AutoValue
-  abstract static class RefasterTemplateTestData {
-
-    abstract String templateName();
-
-    abstract String templateTestContent();
-  }
-
-  @AutoValue
-  abstract static class RefasterTemplateCollectionTestData {
-    abstract String templateCollection();
-
-    abstract boolean isInput();
-
-    abstract List<RefasterTemplateTestData> templateTests();
-  }
-}

documentation-support/src/main/java/tech/picnic/errorprone/documentation/package-info.java

@@ -1,7 +0,0 @@
-/**
- * A Java compiler plugin that extracts data from compiled classes, in support of the Error Prone
- * Support documentation.
- */
-@com.google.errorprone.annotations.CheckReturnValue
-@org.jspecify.annotations.NullMarked
-package tech.picnic.errorprone.documentation;

documentation-support/src/test/java/tech/picnic/errorprone/documentation/BugPatternExtractorTest.java

@@ -1,153 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-
-import com.google.common.io.Resources;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.CompilationTestHelper;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
-import com.google.errorprone.matchers.Description;
-import com.sun.source.tree.ClassTree;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.io.TempDir;
-
-final class BugPatternExtractorTest {
-  @Test
-  void noBugPattern(@TempDir Path outputDirectory) {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerWithoutAnnotation.java",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "",
-        "public final class TestCheckerWithoutAnnotation extends BugChecker {}");
-
-    assertThat(outputDirectory.toAbsolutePath()).isEmptyDirectory();
-  }
-
-  @Test
-  void minimalBugPattern(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "MinimalBugChecker.java",
-        "package pkg;",
-        "",
-        "import com.google.errorprone.BugPattern;",
-        "import com.google.errorprone.BugPattern.SeverityLevel;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "",
-        "@BugPattern(summary = \"MinimalBugChecker summary\", severity = SeverityLevel.ERROR)",
-        "public final class MinimalBugChecker extends BugChecker {}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-MinimalBugChecker.json",
-        "bugpattern-documentation-minimal.json");
-  }
-
-  @Test
-  void completeBugPattern(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "CompleteBugChecker.java",
-        "package pkg;",
-        "",
-        "import com.google.errorprone.BugPattern;",
-        "import com.google.errorprone.BugPattern.SeverityLevel;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "@BugPattern(",
-        "    name = \"OtherName\",",
-        "    summary = \"CompleteBugChecker summary\",",
-        "    linkType = BugPattern.LinkType.CUSTOM,",
-        "    link = \"https://error-prone.picnic.tech\",",
-        "    explanation = \"Example explanation\",",
-        "    severity = SeverityLevel.SUGGESTION,",
-        "    altNames = \"Check\",",
-        "    tags = BugPattern.StandardTags.SIMPLIFICATION,",
-        "    disableable = false,",
-        "    suppressionAnnotations = {BugPattern.class, Test.class})",
-        "public final class CompleteBugChecker extends BugChecker {}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-CompleteBugChecker.json",
-        "bugpattern-documentation-complete.json");
-  }
-
-  @Test
-  void undocumentedSuppressionBugPattern(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "UndocumentedSuppressionBugPattern.java",
-        "package pkg;",
-        "",
-        "import com.google.errorprone.BugPattern;",
-        "import com.google.errorprone.BugPattern.SeverityLevel;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "",
-        "@BugPattern(",
-        "    summary = \"UndocumentedSuppressionBugPattern summary\",",
-        "    severity = SeverityLevel.WARNING,",
-        "    documentSuppression = false)",
-        "public final class UndocumentedSuppressionBugPattern extends BugChecker {}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-UndocumentedSuppressionBugPattern.json",
-        "bugpattern-documentation-undocumented-suppression.json");
-  }
-
-  @Test
-  void bugPatternAnnotationIsAbsent() {
-    CompilationTestHelper.newInstance(TestChecker.class, getClass())
-        .addSourceLines(
-            "TestChecker.java",
-            "import com.google.errorprone.bugpatterns.BugChecker;",
-            "",
-            "// BUG: Diagnostic contains: Can extract: false",
-            "public final class TestChecker extends BugChecker {}")
-        .doTest();
-  }
-
-  private static void verifyFileMatchesResource(
-      Path outputDirectory, String fileName, String resourceName) throws IOException {
-    assertThat(Files.readString(outputDirectory.resolve(fileName)))
-        .isEqualToIgnoringWhitespace(getResource(resourceName));
-  }
-
-  // XXX: Once we support only JDK 15+, drop this method in favour of including the resources as
-  // text blocks in this class. (This also requires renaming the `verifyFileMatchesResource`
-  // method.)
-  private static String getResource(String resourceName) throws IOException {
-    return Resources.toString(
-        Resources.getResource(BugPatternExtractorTest.class, resourceName), UTF_8);
-  }
-
-  /** A {@link BugChecker} that validates the {@link BugPatternExtractor}. */
-  @BugPattern(summary = "Validates `BugPatternExtractor` extraction", severity = ERROR)
-  public static final class TestChecker extends BugChecker implements ClassTreeMatcher {
-    private static final long serialVersionUID = 1L;
-
-    @Override
-    public Description matchClass(ClassTree tree, VisitorState state) {
-      BugPatternExtractor extractor = new BugPatternExtractor();
-
-      assertThatThrownBy(() -> extractor.extract(tree, state.context, null))
-          .isInstanceOf(NullPointerException.class)
-          .hasMessage("BugPattern annotation must be present");
-
-      return buildDescription(tree)
-          .setMessage(String.format("Can extract: %s", extractor.canExtract(tree, state)))
-          .build();
-    }
-  }
-}

documentation-support/src/test/java/tech/picnic/errorprone/documentation/BugPatternTestExtractorTest.java

@@ -1,337 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static java.nio.charset.StandardCharsets.UTF_8;
-import static org.assertj.core.api.Assertions.assertThat;
-
-import com.google.common.io.Resources;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.io.TempDir;
-
-final class BugPatternTestExtractorTest {
-  @Test
-  void noBugPatternTest(@TempDir Path outputDirectory) {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerWithoutAnnotation.java",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "",
-        "public final class TestCheckerWithoutAnnotation extends BugChecker {}");
-
-    assertThat(outputDirectory.toAbsolutePath()).isEmptyDirectory();
-  }
-
-  @Test
-  void minimalBugPatternTest(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  CompilationTestHelper compilationTestHelper = CompilationTestHelper.newInstance(TestChecker.class, getClass());",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-minimal.json");
-  }
-
-  @Test
-  void differentBugPatternAsClassVariableTest(@TempDir Path outputDirectory) {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class DifferentChecker extends BugChecker {}",
-        "",
-        "  CompilationTestHelper compilationTestHelper = CompilationTestHelper.newInstance(DifferentChecker.class, getClass());",
-        "}");
-
-    assertThat(outputDirectory.toAbsolutePath()).isEmptyDirectory();
-  }
-
-  @Test
-  void differentBugPatternAsLocalVariable(@TempDir Path outputDirectory) {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class DifferentChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void identification() {",
-        "    CompilationTestHelper.newInstance(DifferentChecker.class, getClass())",
-        "        .addSourceLines(\"A.java\", \"class A {}\")",
-        "        .doTest();",
-        "  }",
-        "}");
-
-    assertThat(outputDirectory.toAbsolutePath()).isEmptyDirectory();
-  }
-
-  @Test
-  void bugPatternTestSingleIdentification(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void identification() {",
-        "    CompilationTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addSourceLines(\"A.java\", \"class A {}\")",
-        "        .doTest();",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-identification.json");
-  }
-
-  @Test
-  void bugPatternTestIdentificationMultipleSourceLines(@TempDir Path outputDirectory)
-      throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "package pkg;",
-        "",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void identification() {",
-        "    CompilationTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addSourceLines(\"A.java\", \"class A {}\")",
-        "        .addSourceLines(\"B.java\", \"class B {}\")",
-        "        .doTest();",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-identification-two-sources.json");
-  }
-
-  @Test
-  void bugPatternTestSingleReplacement(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void replacement() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addInputLines(\"A.java\", \"class A {}\")",
-        "        .addOutputLines(\"A.java\", \"class A {}\")",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-replacement.json");
-  }
-
-  @Test
-  void bugPatternTestMultipleReplacementSources(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void replacement() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addInputLines(\"A.java\", \"class A {}\")",
-        "        .addOutputLines(\"A.java\", \"class A {}\")",
-        "        .addInputLines(\"B.java\", \"class B {}\")",
-        "        .addOutputLines(\"B.java\", \"class B {}\")",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-replacement-two-sources.json");
-  }
-
-  @Test
-  void bugPatternReplacementExpectUnchanged(@TempDir Path outputDirectory) throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void replacement() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addInputLines(\"A.java\", \"class A {}\")",
-        "        .expectUnchanged()",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-replacement-expect-unchanged.json");
-  }
-
-  @Test
-  void bugPatternTestIdentificationAndReplacement(@TempDir Path outputDirectory)
-      throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void identification() {",
-        "    CompilationTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addSourceLines(\"A.java\", \"class A {}\")",
-        "        .doTest();",
-        "  }",
-        "",
-        "  @Test",
-        "  void replacement() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addInputLines(\"A.java\", \"class A {}\")",
-        "        .addOutputLines(\"A.java\", \"class A {}\")",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-identification-and-replacement.json");
-  }
-
-  @Test
-  void bugPatternTestMultipleIdentificationAndReplacement(@TempDir Path outputDirectory)
-      throws IOException {
-    Compilation.compileWithDocumentationGenerator(
-        outputDirectory,
-        "TestCheckerTest.java",
-        "package pkg;",
-        "",
-        "import static com.google.errorprone.BugCheckerRefactoringTestHelper.FixChoosers.SECOND;",
-        "",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper;",
-        "import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;",
-        "import com.google.errorprone.bugpatterns.BugChecker;",
-        "import com.google.errorprone.CompilationTestHelper;",
-        "import org.junit.jupiter.api.Test;",
-        "",
-        "final class TestCheckerTest {",
-        "  private static class TestChecker extends BugChecker {}",
-        "",
-        "  @Test",
-        "  void identification() {",
-        "    CompilationTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addSourceLines(\"A.java\", \"class A {}\")",
-        "        .doTest();",
-        "  }",
-        "",
-        "  @Test",
-        "  void identification2() {",
-        "    CompilationTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addSourceLines(\"B.java\", \"class B {}\")",
-        "        .doTest();",
-        "  }",
-        "",
-        "  @Test",
-        "  void replacementFirstSuggestedFix() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .addInputLines(\"A.java\", \"class A {}\")",
-        "        .addOutputLines(\"A.java\", \"class A {}\")",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "",
-        "  @Test",
-        "  void replacementSecondSuggestedFix() {",
-        "    BugCheckerRefactoringTestHelper.newInstance(TestChecker.class, getClass())",
-        "        .setFixChooser(SECOND)",
-        "        .addInputLines(\"B.java\", \"class B {}\")",
-        "        .addOutputLines(\"B.java\", \"class B {}\")",
-        "        .doTest(TestMode.TEXT_MATCH);",
-        "  }",
-        "}");
-
-    verifyFileMatchesResource(
-        outputDirectory,
-        "bugpattern-test-TestCheckerTest.json",
-        "bugpattern-test-documentation-multiple-identification-and-replacement.json");
-  }
-
-  private static void verifyFileMatchesResource(
-      Path outputDirectory, String fileName, String resourceName) throws IOException {
-    assertThat(Files.readString(outputDirectory.resolve(fileName)))
-        .isEqualToIgnoringWhitespace(getResource(resourceName));
-  }
-
-  // XXX: Once we support only JDK 15+, drop this method in favour of including the resources as
-  // text blocks in this class. (This also requires renaming the `verifyFileMatchesResource`
-  // method.)
-  private static String getResource(String resourceName) throws IOException {
-    return Resources.toString(
-        Resources.getResource(BugPatternTestExtractorTest.class, resourceName), UTF_8);
-  }
-}

documentation-support/src/test/java/tech/picnic/errorprone/documentation/Compilation.java

@@ -1,45 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.FileManagers;
-import com.google.errorprone.FileObjects;
-import com.sun.tools.javac.api.JavacTaskImpl;
-import com.sun.tools.javac.api.JavacTool;
-import com.sun.tools.javac.file.JavacFileManager;
-import java.nio.file.Path;
-import javax.tools.JavaCompiler;
-import javax.tools.JavaFileObject;
-
-// XXX: Generalize and move this class so that it can also be used by `refaster-compiler`.
-// XXX: Add support for this class to the `ErrorProneTestHelperSourceFormat` check.
-public final class Compilation {
-  private Compilation() {}
-
-  public static void compileWithDocumentationGenerator(
-      Path outputDirectory, String fileName, String... lines) {
-    compileWithDocumentationGenerator(outputDirectory.toAbsolutePath().toString(), fileName, lines);
-  }
-
-  public static void compileWithDocumentationGenerator(
-      String outputDirectory, String fileName, String... lines) {
-    compile(
-        ImmutableList.of("-Xplugin:DocumentationGenerator -XoutputDirectory=" + outputDirectory),
-        FileObjects.forSourceLines(fileName, lines));
-  }
-
-  private static void compile(ImmutableList<String> options, JavaFileObject javaFileObject) {
-    JavacFileManager javacFileManager = FileManagers.testFileManager();
-    JavaCompiler compiler = JavacTool.create();
-    JavacTaskImpl task =
-        (JavacTaskImpl)
-            compiler.getTask(
-                null,
-                javacFileManager,
-                null,
-                options,
-                ImmutableList.of(),
-                ImmutableList.of(javaFileObject));
-
-    task.call();
-  }
-}

documentation-support/src/test/java/tech/picnic/errorprone/documentation/DocumentationGeneratorTaskListenerTest.java

@@ -1,77 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static com.google.common.collect.ImmutableList.toImmutableList;
-import static java.nio.file.attribute.AclEntryPermission.ADD_SUBDIRECTORY;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-import static org.junit.jupiter.api.condition.OS.WINDOWS;
-
-import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.Sets;
-import java.io.IOException;
-import java.nio.file.FileSystemException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.attribute.AclEntry;
-import java.nio.file.attribute.AclFileAttributeView;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.condition.DisabledOnOs;
-import org.junit.jupiter.api.condition.EnabledOnOs;
-import org.junit.jupiter.api.io.TempDir;
-
-final class DocumentationGeneratorTaskListenerTest {
-  @EnabledOnOs(WINDOWS)
-  @Test
-  void readOnlyFileSystemWindows(@TempDir Path outputDirectory) throws IOException {
-    AclFileAttributeView view =
-        Files.getFileAttributeView(outputDirectory, AclFileAttributeView.class);
-    view.setAcl(
-        view.getAcl().stream()
-            .map(
-                entry ->
-                    AclEntry.newBuilder(entry)
-                        .setPermissions(
-                            Sets.difference(entry.permissions(), ImmutableSet.of(ADD_SUBDIRECTORY)))
-                        .build())
-            .collect(toImmutableList()));
-
-    readOnlyFileSystemFailsToWrite(outputDirectory.resolve("nonexistent"));
-  }
-
-  @DisabledOnOs(WINDOWS)
-  @Test
-  void readOnlyFileSystemNonWindows(@TempDir Path outputDirectory) {
-    assertThat(outputDirectory.toFile().setWritable(false))
-        .describedAs("Failed to make test directory unwritable")
-        .isTrue();
-
-    readOnlyFileSystemFailsToWrite(outputDirectory.resolve("nonexistent"));
-  }
-
-  private static void readOnlyFileSystemFailsToWrite(Path outputDirectory) {
-    assertThatThrownBy(
-            () ->
-                Compilation.compileWithDocumentationGenerator(
-                    outputDirectory, "A.java", "class A {}"))
-        .hasRootCauseInstanceOf(FileSystemException.class)
-        .hasCauseInstanceOf(IllegalStateException.class)
-        .hasMessageEndingWith("Error while creating directory with path '%s'", outputDirectory);
-  }
-
-  @Test
-  void noClassNoOutput(@TempDir Path outputDirectory) {
-    Compilation.compileWithDocumentationGenerator(outputDirectory, "A.java", "package pkg;");
-
-    assertThat(outputDirectory).isEmptyDirectory();
-  }
-
-  @Test
-  void excessArguments(@TempDir Path outputDirectory) {
-    assertThatThrownBy(
-            () ->
-                Compilation.compileWithDocumentationGenerator(
-                    outputDirectory.toAbsolutePath() + " extra-arg", "A.java", "package pkg;"))
-        .isInstanceOf(IllegalArgumentException.class)
-        .hasMessage("Precisely one path must be provided");
-  }
-}

documentation-support/src/test/java/tech/picnic/errorprone/documentation/DocumentationGeneratorTest.java

@@ -1,38 +0,0 @@
-package tech.picnic.errorprone.documentation;
-
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatThrownBy;
-import static tech.picnic.errorprone.documentation.DocumentationGenerator.OUTPUT_DIRECTORY_FLAG;
-
-import java.nio.file.InvalidPathException;
-import java.nio.file.Path;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.params.ParameterizedTest;
-import org.junit.jupiter.params.provider.ValueSource;
-
-final class DocumentationGeneratorTest {
-  @ParameterizedTest
-  @ValueSource(strings = {"bar", "foo"})
-  void getOutputPath(String path) {
-    assertThat(DocumentationGenerator.getOutputPath(OUTPUT_DIRECTORY_FLAG + '=' + path))
-        .isEqualTo(Path.of(path));
-  }
-
-  @ParameterizedTest
-  @ValueSource(strings = {"", "-XoutputDirectory", "invalidOption=Test", "nothing"})
-  void getOutputPathWithInvalidArgument(String pathArg) {
-    assertThatThrownBy(() -> DocumentationGenerator.getOutputPath(pathArg))
-        .isInstanceOf(IllegalArgumentException.class)
-        .hasMessage("'%s' must be of the form '%s=<value>'", pathArg, OUTPUT_DIRECTORY_FLAG);
-  }
-
-  @Test
-  void getOutputPathWithInvalidPath() {
-    String basePath = "path-with-null-char-\0";
-    assertThatThrownBy(
-            () -> DocumentationGenerator.getOutputPath(OUTPUT_DIRECTORY_FLAG + '=' + basePath))
-        .isInstanceOf(IllegalArgumentException.class)
-        .hasCauseInstanceOf(InvalidPathException.class)
-        .hasMessageEndingWith("Invalid path '%s'", basePath);
-  }
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-documentation-complete.json

@@ -1,19 +0,0 @@
-{
-  "fullyQualifiedName": "pkg.CompleteBugChecker",
-  "name": "OtherName",
-  "altNames": [
-    "Check"
-  ],
-  "link": "https://error-prone.picnic.tech",
-  "tags": [
-    "Simplification"
-  ],
-  "summary": "CompleteBugChecker summary",
-  "explanation": "Example explanation",
-  "severityLevel": "SUGGESTION",
-  "canDisable": false,
-  "suppressionAnnotations": [
-    "com.google.errorprone.BugPattern",
-    "org.junit.jupiter.api.Test"
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-documentation-minimal.json

@@ -1,14 +0,0 @@
-{
-  "fullyQualifiedName": "pkg.MinimalBugChecker",
-  "name": "MinimalBugChecker",
-  "altNames": [],
-  "link": "",
-  "tags": [],
-  "summary": "MinimalBugChecker summary",
-  "explanation": "",
-  "severityLevel": "ERROR",
-  "canDisable": true,
-  "suppressionAnnotations": [
-    "java.lang.SuppressWarnings"
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-documentation-undocumented-suppression.json

@@ -1,12 +0,0 @@
-{
-  "fullyQualifiedName": "pkg.UndocumentedSuppressionBugPattern",
-  "name": "UndocumentedSuppressionBugPattern",
-  "altNames": [],
-  "link": "",
-  "tags": [],
-  "summary": "UndocumentedSuppressionBugPattern summary",
-  "explanation": "",
-  "severityLevel": "WARNING",
-  "canDisable": true,
-  "suppressionAnnotations": []
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-identification-and-replacement.json

@@ -1,12 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [
-    "class A {}\n"
-  ],
-  "replacementTests": [
-    {
-      "inputLines": "class A {}\n",
-      "outputLines": "class A {}\n"
-    }
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-identification-two-sources.json

@@ -1,8 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [
-    "class B {}\n",
-    "class A {}\n"
-  ],
-  "replacementTests": []
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-identification.json

@@ -1,7 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [
-    "class A {}\n"
-  ],
-  "replacementTests": []
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-minimal.json

@@ -1,5 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [],
-  "replacementTests": []
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-multiple-identification-and-replacement.json

@@ -1,17 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [
-    "class A {}\n",
-    "class B {}\n"
-  ],
-  "replacementTests": [
-    {
-      "inputLines": "class A {}\n",
-      "outputLines": "class A {}\n"
-    },
-    {
-      "inputLines": "class B {}\n",
-      "outputLines": "class B {}\n"
-    }
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-replacement-expect-unchanged.json

@@ -1,10 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [],
-  "replacementTests": [
-    {
-      "inputLines": "class A {}\n",
-      "outputLines": ""
-    }
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-replacement-two-sources.json

@@ -1,14 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [],
-  "replacementTests": [
-    {
-      "inputLines": "class B {}\n",
-      "outputLines": "class B {}\n"
-    },
-    {
-      "inputLines": "class A {}\n",
-      "outputLines": "class A {}\n"
-    }
-  ]
-}

documentation-support/src/test/resources/tech/picnic/errorprone/documentation/bugpattern-test-documentation-replacement.json

@@ -1,10 +0,0 @@
-{
-  "name": "TestChecker",
-  "identificationTests": [],
-  "replacementTests": [
-    {
-      "inputLines": "class A {}\n",
-      "outputLines": "class A {}\n"
-    }
-  ]
-}

error-prone-contrib/pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>tech.picnic.error-prone-support</groupId>
         <artifactId>error-prone-support</artifactId>
-        <version>0.8.1-SNAPSHOT</version>
+        <version>0.3.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>error-prone-contrib</artifactId>
@@ -39,14 +39,6 @@
             <artifactId>error_prone_test_helpers</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>${project.groupId}</groupId>
-            <artifactId>documentation-support</artifactId>
-            <!-- This dependency is declared only as a hint to Maven that
-            compilation depends on it; see the `maven-compiler-plugin`'s
-            `annotationProcessorPaths` configuration below. -->
-            <scope>provided</scope>
-        </dependency>
         <dependency>
             <groupId>${project.groupId}</groupId>
             <artifactId>refaster-support</artifactId>
@@ -72,6 +64,11 @@
             <artifactId>auto-service-annotations</artifactId>
             <scope>provided</scope>
         </dependency>
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>jsr305</artifactId>
+            <scope>provided</scope>
+        </dependency>
         <dependency>
             <groupId>com.google.googlejavaformat</groupId>
             <artifactId>google-java-format</artifactId>
@@ -101,11 +98,6 @@
             <artifactId>reactor-adapter</artifactId>
             <scope>provided</scope>
         </dependency>
-        <dependency>
-            <groupId>io.projectreactor.addons</groupId>
-            <artifactId>reactor-extra</artifactId>
-            <scope>provided</scope>
-        </dependency>
         <dependency>
             <groupId>io.reactivex.rxjava2</groupId>
             <artifactId>rxjava</artifactId>
@@ -154,7 +146,7 @@
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-api</artifactId>
-            <scope>provided</scope>
+            <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
@@ -181,11 +173,6 @@
             <artifactId>slf4j-api</artifactId>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>org.springframework</groupId>
-            <artifactId>spring-context</artifactId>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-test</artifactId>
@@ -221,11 +208,6 @@
                     <artifactId>maven-compiler-plugin</artifactId>
                     <configuration>
                         <annotationProcessorPaths combine.children="append">
-                            <path>
-                                <groupId>${project.groupId}</groupId>
-                                <artifactId>documentation-support</artifactId>
-                                <version>${project.version}</version>
-                            </path>
                             <path>
                                 <groupId>${project.groupId}</groupId>
                                 <artifactId>refaster-compiler</artifactId>
@@ -239,7 +221,6 @@
                         </annotationProcessorPaths>
                         <compilerArgs combine.children="append">
                             <arg>-Xplugin:RefasterRuleCompiler</arg>
-                            <arg>-Xplugin:DocumentationGenerator -XoutputDirectory=${project.build.directory}/docs</arg>
                         </compilerArgs>
                     </configuration>
                 </plugin>
@@ -257,4 +238,33 @@
             </plugins>
         </pluginManagement>
     </build>
+
+    <profiles>
+        <profile>
+            <id>docgen</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.codehaus.mojo</groupId>
+                        <artifactId>build-helper-maven-plugin</artifactId>
+                        <version>3.3.0</version>
+                        <executions>
+                            <execution>
+                                <id>add-test-source</id>
+                                <goals>
+                                    <goal>add-test-source</goal>
+                                </goals>
+                                <phase>generate-test-sources</phase>
+                                <configuration>
+                                    <sources>
+                                        <source>src/test/resources</source>
+                                    </sources>
+                                </configuration>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
 </project>

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AmbiguousJsonCreator.java

@@ -36,9 +36,6 @@ public final class AmbiguousJsonCreator extends BugChecker implements Annotation
   private static final Matcher<AnnotationTree> IS_JSON_CREATOR_ANNOTATION =
       isType("com.fasterxml.jackson.annotation.JsonCreator");
 
-  /** Instantiates a new {@link AmbiguousJsonCreator} instance. */
-  public AmbiguousJsonCreator() {}
-
   @Override
   public Description matchAnnotation(AnnotationTree tree, VisitorState state) {
     if (!IS_JSON_CREATOR_ANNOTATION.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AssertJIsNull.java

@@ -44,9 +44,6 @@ public final class AssertJIsNull extends BugChecker implements MethodInvocationT
           argumentCount(1),
           argument(0, nullLiteral()));
 
-  /** Instantiates a new {@link AssertJIsNull} instance. */
-  public AssertJIsNull() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (!ASSERT_IS_EQUAL_TO_NULL.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/AutowiredConstructor.java

@@ -15,6 +15,7 @@ import com.google.errorprone.BugPattern;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker;
 import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
+import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.MultiMatcher;
 import com.google.errorprone.util.ASTHelpers;
@@ -23,7 +24,6 @@ import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.MethodTree;
 import com.sun.source.tree.Tree;
 import java.util.List;
-import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags redundant {@code @Autowired} constructor annotations. */
 @AutoService(BugChecker.class)
@@ -38,9 +38,6 @@ public final class AutowiredConstructor extends BugChecker implements ClassTreeM
   private static final MultiMatcher<Tree, AnnotationTree> AUTOWIRED_ANNOTATION =
       annotations(AT_LEAST_ONE, isType("org.springframework.beans.factory.annotation.Autowired"));
 
-  /** Instantiates a new {@link AutowiredConstructor} instance. */
-  public AutowiredConstructor() {}
-
   @Override
   public Description matchClass(ClassTree tree, VisitorState state) {
     List<MethodTree> constructors = ASTHelpers.getConstructors(tree);
@@ -62,6 +59,6 @@ public final class AutowiredConstructor extends BugChecker implements ClassTreeM
      * leave flagging the unused import to Error Prone's `RemoveUnusedImports` check.
      */
     AnnotationTree annotation = Iterables.getOnlyElement(annotations);
-    return describeMatch(annotation, SourceCode.deleteWithTrailingWhitespace(annotation, state));
+    return describeMatch(annotation, SuggestedFix.delete(annotation));
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CanonicalAnnotationSyntax.java

@@ -46,9 +46,6 @@ public final class CanonicalAnnotationSyntax extends BugChecker implements Annot
               CanonicalAnnotationSyntax::dropRedundantValueAttribute,
               CanonicalAnnotationSyntax::dropRedundantCurlies);
 
-  /** Instantiates a new {@link CanonicalAnnotationSyntax} instance. */
-  public CanonicalAnnotationSyntax() {}
-
   @Override
   public Description matchAnnotation(AnnotationTree tree, VisitorState state) {
     return FIX_FACTORIES.stream()

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CollectorMutability.java

@@ -18,7 +18,6 @@ import com.google.errorprone.matchers.Matcher;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MethodInvocationTree;
 import java.util.stream.Collector;
-import tech.picnic.errorprone.bugpatterns.util.ThirdPartyLibrary;
 
 /**
  * A {@link BugChecker} that flags {@link Collector Collectors} that don't clearly express
@@ -46,13 +45,9 @@ public final class CollectorMutability extends BugChecker implements MethodInvoc
   private static final Matcher<ExpressionTree> SET_COLLECTOR =
       staticMethod().anyClass().named("toSet");
 
-  /** Instantiates a new {@link CollectorMutability} instance. */
-  public CollectorMutability() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    if (!ThirdPartyLibrary.GUAVA.isIntroductionAllowed(state)
-        || !COLLECTOR_METHOD.matches(tree, state)) {
+    if (!COLLECTOR_METHOD.matches(tree, state)) {
       return Description.NO_MATCH;
     }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/EmptyMethod.java

@@ -14,6 +14,7 @@ import com.google.errorprone.BugPattern;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker;
 import com.google.errorprone.bugpatterns.BugChecker.MethodTreeMatcher;
+import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matcher;
 import com.google.errorprone.util.ASTHelpers;
@@ -21,7 +22,6 @@ import com.sun.source.tree.ClassTree;
 import com.sun.source.tree.MethodTree;
 import com.sun.source.tree.Tree;
 import java.util.Optional;
-import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags empty methods that seemingly can simply be deleted. */
 @AutoService(BugChecker.class)
@@ -38,9 +38,6 @@ public final class EmptyMethod extends BugChecker implements MethodTreeMatcher {
           AT_LEAST_ONE,
           anyOf(isType("java.lang.Override"), isType("org.aspectj.lang.annotation.Pointcut")));
 
-  /** Instantiates a new {@link EmptyMethod} instance. */
-  public EmptyMethod() {}
-
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
     if (tree.getBody() == null
@@ -55,7 +52,7 @@ public final class EmptyMethod extends BugChecker implements MethodTreeMatcher {
       return Description.NO_MATCH;
     }
 
-    return describeMatch(tree, SourceCode.deleteWithTrailingWhitespace(tree, state));
+    return describeMatch(tree, SuggestedFix.delete(tree));
   }
 
   private static boolean isInPossibleTestHelperClass(VisitorState state) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ErrorProneTestHelperSourceFormat.java

@@ -72,9 +72,6 @@ public final class ErrorProneTestHelperSourceFormat extends BugChecker
           .onDescendantOf("com.google.errorprone.BugCheckerRefactoringTestHelper.ExpectOutput")
           .named("addOutputLines");
 
-  /** Instantiates a new {@link ErrorProneTestHelperSourceFormat} instance. */
-  public ErrorProneTestHelperSourceFormat() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     boolean isOutputSource = OUTPUT_SOURCE_ACCEPTING_METHOD.matches(tree, state);

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ExplicitEnumOrdering.java

@@ -46,9 +46,6 @@ public final class ExplicitEnumOrdering extends BugChecker implements MethodInvo
   private static final Matcher<ExpressionTree> EXPLICIT_ORDERING =
       staticMethod().onClass(Ordering.class.getName()).named("explicit");
 
-  /** Instantiates a new {@link ExplicitEnumOrdering} instance. */
-  public ExplicitEnumOrdering() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (!EXPLICIT_ORDERING.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/FluxFlatMapUsage.java

@@ -5,10 +5,6 @@ import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
 import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
 import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.generic;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.subOf;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.type;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.unbound;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.Iterables;
@@ -21,14 +17,11 @@ import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.fixes.SuggestedFixes;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.suppliers.Supplier;
-import com.google.errorprone.suppliers.Suppliers;
-import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.ExpressionTree;
 import com.sun.source.tree.MemberReferenceTree;
 import com.sun.source.tree.MethodInvocationTree;
-import com.sun.tools.javac.code.Type;
 import java.util.function.Function;
+import java.util.function.Supplier;
 import reactor.core.publisher.Flux;
 
 /**
@@ -40,12 +33,11 @@ import reactor.core.publisher.Flux;
  * former interleaves values as they are emitted, yielding nondeterministic results. In most cases
  * {@link Flux#concatMap(Function)} should be preferred, as it produces consistent results and
  * avoids potentially saturating the thread pool on which subscription happens. If {@code
- * concatMap}'s sequential-subscription semantics are undesirable one should invoke a {@code
- * flatMap} or {@code flatMapSequential} overload with an explicit concurrency level.
+ * concatMap}'s single-subscription semantics are undesirable one should invoke a {@code flatMap} or
+ * {@code flatMapSequential} overload with an explicit concurrency level.
  *
- * <p>NB: The rarely-used overload {@link Flux#flatMap(Function, Function,
- * java.util.function.Supplier)} is not flagged by this check because there is no clear alternative
- * to point to.
+ * <p>NB: The rarely-used overload {@link Flux#flatMap(Function, Function, Supplier)} is not flagged
+ * by this check because there is no clear alternative to point to.
  */
 @AutoService(BugChecker.class)
 @BugPattern(
@@ -60,19 +52,11 @@ public final class FluxFlatMapUsage extends BugChecker
     implements MethodInvocationTreeMatcher, MemberReferenceTreeMatcher {
   private static final long serialVersionUID = 1L;
   private static final String MAX_CONCURRENCY_ARG_NAME = "MAX_CONCURRENCY";
-  private static final Supplier<Type> FLUX =
-      Suppliers.typeFromString("reactor.core.publisher.Flux");
   private static final Matcher<ExpressionTree> FLUX_FLATMAP =
       instanceMethod()
-          .onDescendantOf(FLUX)
+          .onDescendantOf("reactor.core.publisher.Flux")
           .namedAnyOf("flatMap", "flatMapSequential")
           .withParameters(Function.class.getName());
-  private static final Supplier<Type> FLUX_OF_PUBLISHERS =
-      VisitorState.memoize(
-          generic(FLUX, subOf(generic(type("org.reactivestreams.Publisher"), unbound()))));
-
-  /** Instantiates a new {@link FluxFlatMapUsage} instance. */
-  public FluxFlatMapUsage() {}
 
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
@@ -80,27 +64,14 @@ public final class FluxFlatMapUsage extends BugChecker
       return Description.NO_MATCH;
     }
 
-    SuggestedFix serializationFix = SuggestedFixes.renameMethodInvocation(tree, "concatMap", state);
-    SuggestedFix concurrencyCapFix =
-        SuggestedFix.builder()
-            .postfixWith(
-                Iterables.getOnlyElement(tree.getArguments()), ", " + MAX_CONCURRENCY_ARG_NAME)
-            .build();
-
-    Description.Builder description = buildDescription(tree);
-
-    if (state.getTypes().isSubtype(ASTHelpers.getType(tree), FLUX_OF_PUBLISHERS.get(state))) {
-      /*
-       * Nested publishers may need to be subscribed to eagerly in order to avoid a deadlock, e.g.
-       * if they are produced by `Flux#groupBy`. In this case we suggest specifying an explicit
-       * concurrently bound, in favour of sequential subscriptions using `Flux#concatMap`.
-       */
-      description.addFix(concurrencyCapFix).addFix(serializationFix);
-    } else {
-      description.addFix(serializationFix).addFix(concurrencyCapFix);
-    }
-
-    return description.build();
+    return buildDescription(tree)
+        .addFix(SuggestedFixes.renameMethodInvocation(tree, "concatMap", state))
+        .addFix(
+            SuggestedFix.builder()
+                .postfixWith(
+                    Iterables.getOnlyElement(tree.getArguments()), ", " + MAX_CONCURRENCY_ARG_NAME)
+                .build())
+        .build();
   }
 
   @Override

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/FormatStringConcatenation.java

@@ -32,7 +32,7 @@ import com.sun.source.util.SimpleTreeVisitor;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
-import org.jspecify.annotations.Nullable;
+import javax.annotation.Nullable;
 import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
@@ -129,9 +129,6 @@ public final class FormatStringConcatenation extends BugChecker
           .onDescendantOf("org.slf4j.Logger")
           .namedAnyOf("debug", "error", "info", "trace", "warn");
 
-  /** Instantiates a new {@link FormatStringConcatenation} instance. */
-  public FormatStringConcatenation() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (hasNonConstantStringConcatenationArgument(tree, 0, state)) {
@@ -207,7 +204,7 @@ public final class FormatStringConcatenation extends BugChecker
   }
 
   private static class ReplacementArgumentsConstructor
-      extends SimpleTreeVisitor<@Nullable Void, VisitorState> {
+      extends SimpleTreeVisitor<Void, VisitorState> {
     private final StringBuilder formatString = new StringBuilder();
     private final List<Tree> formatArguments = new ArrayList<>();
     private final String formatSpecifier;
@@ -216,8 +213,9 @@ public final class FormatStringConcatenation extends BugChecker
       this.formatSpecifier = formatSpecifier;
     }
 
+    @Nullable
     @Override
-    public @Nullable Void visitBinary(BinaryTree tree, VisitorState state) {
+    public Void visitBinary(BinaryTree tree, VisitorState state) {
       if (tree.getKind() == Kind.PLUS && isStringTyped(tree, state)) {
         tree.getLeftOperand().accept(this, state);
         tree.getRightOperand().accept(this, state);
@@ -228,13 +226,15 @@ public final class FormatStringConcatenation extends BugChecker
       return null;
     }
 
+    @Nullable
     @Override
-    public @Nullable Void visitParenthesized(ParenthesizedTree tree, VisitorState state) {
+    public Void visitParenthesized(ParenthesizedTree tree, VisitorState state) {
       return tree.getExpression().accept(this, state);
     }
 
+    @Nullable
     @Override
-    protected @Nullable Void defaultAction(Tree tree, VisitorState state) {
+    protected Void defaultAction(Tree tree, VisitorState state) {
       appendExpression(tree);
       return null;
     }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/IdentityConversion.java

@@ -23,7 +23,6 @@ import com.google.errorprone.matchers.Matcher;
 import com.google.errorprone.util.ASTHelpers;
 import com.google.errorprone.util.ASTHelpers.TargetType;
 import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.MemberSelectTree;
 import com.sun.source.tree.MethodInvocationTree;
 import com.sun.tools.javac.code.Type;
 import com.sun.tools.javac.code.Types;
@@ -33,7 +32,7 @@ import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags redundant identity conversions. */
 // XXX: Consider detecting cases where a flagged expression is passed to a method, and where removal
-// of the identity conversion would cause a different method overload to be selected. Depending on
+// of the identify conversion would cause a different method overload to be selected. Depending on
 // the target method such a modification may change the code's semantics or performance.
 @AutoService(BugChecker.class)
 @BugPattern(
@@ -46,13 +45,6 @@ public final class IdentityConversion extends BugChecker implements MethodInvoca
   private static final long serialVersionUID = 1L;
   private static final Matcher<ExpressionTree> IS_CONVERSION_METHOD =
       anyOf(
-          staticMethod()
-              .onClassAny(
-                  Primitives.allWrapperTypes().stream()
-                      .map(Class::getName)
-                      .collect(toImmutableSet()))
-              .named("valueOf"),
-          staticMethod().onClass(String.class.getName()).named("valueOf"),
           staticMethod()
               .onClassAny(
                   "com.google.common.collect.ImmutableBiMap",
@@ -68,17 +60,18 @@ public final class IdentityConversion extends BugChecker implements MethodInvoca
                   "com.google.common.collect.ImmutableTable")
               .named("copyOf"),
           staticMethod()
-              .onClass("com.google.errorprone.matchers.Matchers")
-              .namedAnyOf("allOf", "anyOf"),
+              .onClassAny(
+                  Primitives.allWrapperTypes().stream()
+                      .map(Class::getName)
+                      .collect(toImmutableSet()))
+              .named("valueOf"),
+          staticMethod().onClass(String.class.getName()).named("valueOf"),
           staticMethod().onClass("reactor.adapter.rxjava.RxJava2Adapter"),
           staticMethod()
               .onClass("reactor.core.publisher.Flux")
               .namedAnyOf("concat", "firstWithSignal", "from", "merge"),
           staticMethod().onClass("reactor.core.publisher.Mono").namedAnyOf("from", "fromDirect"));
 
-  /** Instantiates a new {@link IdentityConversion} instance. */
-  public IdentityConversion() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     List<? extends ExpressionTree> arguments = tree.getArguments();
@@ -99,15 +92,6 @@ public final class IdentityConversion extends BugChecker implements MethodInvoca
       return Description.NO_MATCH;
     }
 
-    if (sourceType.isPrimitive()
-        && state.getPath().getParentPath().getLeaf() instanceof MemberSelectTree) {
-      /*
-       * The result of the conversion method is dereferenced, while the source type is a primitive:
-       * dropping the conversion would yield uncompilable code.
-       */
-      return Description.NO_MATCH;
-    }
-
     return buildDescription(tree)
         .setMessage(
             "This method invocation appears redundant; remove it or suppress this warning and "

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ImmutablesSortedSetComparator.java

@@ -67,9 +67,6 @@ public final class ImmutablesSortedSetComparator extends BugChecker implements M
                   hasAnnotation("org.immutables.value.Value.NaturalOrder"),
                   hasAnnotation("org.immutables.value.Value.ReverseOrder"))));
 
-  /** Instantiates a new {@link ImmutablesSortedSetComparator} instance. */
-  public ImmutablesSortedSetComparator() {}
-
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
     if (!METHOD_LACKS_ANNOTATION.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/IsInstanceLambdaUsage.java

@@ -1,60 +0,0 @@
-package tech.picnic.errorprone.bugpatterns;
-
-import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
-import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
-import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
-import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-
-import com.google.auto.service.AutoService;
-import com.google.common.collect.Iterables;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.LambdaExpressionTreeMatcher;
-import com.google.errorprone.fixes.SuggestedFix;
-import com.google.errorprone.matchers.Description;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.InstanceOfTree;
-import com.sun.source.tree.LambdaExpressionTree;
-import com.sun.source.tree.Tree.Kind;
-import com.sun.source.tree.VariableTree;
-import tech.picnic.errorprone.bugpatterns.util.SourceCode;
-
-/**
- * A {@link BugChecker} that flags lambda expressions that can be replaced with a method reference
- * of the form {@code T.class::isInstance}.
- *
- * @see MethodReferenceUsage
- */
-// XXX: Consider folding this logic into the `MethodReferenceUsage` check.
-@AutoService(BugChecker.class)
-@BugPattern(
-    summary = "Prefer `Class::isInstance` method reference over equivalent lambda expression",
-    link = BUG_PATTERNS_BASE_URL + "IsInstanceLambdaUsage",
-    linkType = CUSTOM,
-    severity = SUGGESTION,
-    tags = SIMPLIFICATION)
-public final class IsInstanceLambdaUsage extends BugChecker implements LambdaExpressionTreeMatcher {
-  private static final long serialVersionUID = 1L;
-
-  /** Instantiates a new {@link IsInstanceLambdaUsage} instance. */
-  public IsInstanceLambdaUsage() {}
-
-  @Override
-  public Description matchLambdaExpression(LambdaExpressionTree tree, VisitorState state) {
-    if (tree.getParameters().size() != 1 || tree.getBody().getKind() != Kind.INSTANCE_OF) {
-      return Description.NO_MATCH;
-    }
-
-    VariableTree param = Iterables.getOnlyElement(tree.getParameters());
-    InstanceOfTree instanceOf = (InstanceOfTree) tree.getBody();
-    if (!ASTHelpers.getSymbol(param).equals(ASTHelpers.getSymbol(instanceOf.getExpression()))) {
-      return Description.NO_MATCH;
-    }
-
-    return describeMatch(
-        tree,
-        SuggestedFix.replace(
-            tree, SourceCode.treeToString(instanceOf.getType(), state) + ".class::isInstance"));
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitClassModifiers.java

@@ -1,82 +0,0 @@
-package tech.picnic.errorprone.bugpatterns;
-
-import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
-import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
-import static com.google.errorprone.BugPattern.StandardTags.STYLE;
-import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
-import static com.google.errorprone.matchers.Matchers.allOf;
-import static com.google.errorprone.matchers.Matchers.annotations;
-import static com.google.errorprone.matchers.Matchers.anyOf;
-import static com.google.errorprone.matchers.Matchers.hasMethod;
-import static com.google.errorprone.matchers.Matchers.hasModifier;
-import static com.google.errorprone.matchers.Matchers.isType;
-import static com.google.errorprone.matchers.Matchers.not;
-import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.TEST_METHOD;
-import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.hasMetaAnnotation;
-
-import com.google.auto.service.AutoService;
-import com.google.common.collect.ImmutableSet;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.ClassTreeMatcher;
-import com.google.errorprone.fixes.SuggestedFix;
-import com.google.errorprone.fixes.SuggestedFixes;
-import com.google.errorprone.matchers.Description;
-import com.google.errorprone.matchers.Matcher;
-import com.sun.source.tree.ClassTree;
-import javax.lang.model.element.Modifier;
-
-/**
- * A {@link BugChecker} that flags non-final and non package-private JUnit test class declarations,
- * unless abstract.
- */
-@AutoService(BugChecker.class)
-@BugPattern(
-    summary = "Non-abstract JUnit test classes should be declared package-private and final",
-    linkType = CUSTOM,
-    link = BUG_PATTERNS_BASE_URL + "JUnitClassModifiers",
-    severity = SUGGESTION,
-    tags = STYLE)
-public final class JUnitClassModifiers extends BugChecker implements ClassTreeMatcher {
-  private static final long serialVersionUID = 1L;
-  private static final Matcher<ClassTree> HAS_SPRING_CONFIGURATION_ANNOTATION =
-      annotations(
-          AT_LEAST_ONE,
-          anyOf(
-              isType("org.springframework.context.annotation.Configuration"),
-              hasMetaAnnotation("org.springframework.context.annotation.Configuration")));
-  private static final Matcher<ClassTree> TEST_CLASS_WITH_INCORRECT_MODIFIERS =
-      allOf(
-          hasMethod(TEST_METHOD),
-          not(hasModifier(Modifier.ABSTRACT)),
-          anyOf(
-              hasModifier(Modifier.PRIVATE),
-              hasModifier(Modifier.PROTECTED),
-              hasModifier(Modifier.PUBLIC),
-              allOf(not(hasModifier(Modifier.FINAL)), not(HAS_SPRING_CONFIGURATION_ANNOTATION))));
-
-  /** Instantiates a new {@link JUnitClassModifiers} instance. */
-  public JUnitClassModifiers() {}
-
-  @Override
-  public Description matchClass(ClassTree tree, VisitorState state) {
-    if (!TEST_CLASS_WITH_INCORRECT_MODIFIERS.matches(tree, state)) {
-      return Description.NO_MATCH;
-    }
-
-    SuggestedFix.Builder fixBuilder = SuggestedFix.builder();
-    SuggestedFixes.removeModifiers(
-            tree.getModifiers(),
-            state,
-            ImmutableSet.of(Modifier.PRIVATE, Modifier.PROTECTED, Modifier.PUBLIC))
-        .ifPresent(fixBuilder::merge);
-
-    if (!HAS_SPRING_CONFIGURATION_ANNOTATION.matches(tree, state)) {
-      SuggestedFixes.addModifiers(tree, state, Modifier.FINAL).ifPresent(fixBuilder::merge);
-    }
-
-    return describeMatch(tree, fixBuilder.build());
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/JUnitMethodDeclaration.java

@@ -3,18 +3,19 @@ package tech.picnic.errorprone.bugpatterns;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
+import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
 import static com.google.errorprone.matchers.Matchers.allOf;
+import static com.google.errorprone.matchers.Matchers.annotations;
+import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.enclosingClass;
 import static com.google.errorprone.matchers.Matchers.hasModifier;
-import static com.google.errorprone.matchers.Matchers.not;
+import static com.google.errorprone.matchers.Matchers.isType;
 import static java.util.function.Predicate.not;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.SETUP_OR_TEARDOWN_METHOD;
-import static tech.picnic.errorprone.bugpatterns.util.MoreJUnitMatchers.TEST_METHOD;
+import static tech.picnic.errorprone.bugpatterns.util.JavaKeywords.isReservedKeyword;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.Sets;
 import com.google.errorprone.BugPattern;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker;
@@ -23,12 +24,20 @@ import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.fixes.SuggestedFixes;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matcher;
+import com.google.errorprone.matchers.Matchers;
+import com.google.errorprone.matchers.MultiMatcher;
+import com.google.errorprone.predicates.TypePredicate;
 import com.google.errorprone.util.ASTHelpers;
+import com.sun.source.tree.AnnotationTree;
+import com.sun.source.tree.ClassTree;
+import com.sun.source.tree.ImportTree;
 import com.sun.source.tree.MethodTree;
-import com.sun.tools.javac.code.Symbol.MethodSymbol;
+import com.sun.source.tree.Tree;
+import com.sun.tools.javac.code.Symbol;
 import java.util.Optional;
 import javax.lang.model.element.Modifier;
-import tech.picnic.errorprone.bugpatterns.util.ConflictDetection;
+import javax.lang.model.element.Name;
+import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /** A {@link BugChecker} that flags non-canonical JUnit method declarations. */
 // XXX: Consider introducing a class-level check that enforces that test classes:
@@ -47,19 +56,32 @@ public final class JUnitMethodDeclaration extends BugChecker implements MethodTr
   private static final long serialVersionUID = 1L;
   private static final String TEST_PREFIX = "test";
   private static final ImmutableSet<Modifier> ILLEGAL_MODIFIERS =
-      Sets.immutableEnumSet(Modifier.PRIVATE, Modifier.PROTECTED, Modifier.PUBLIC);
-  private static final Matcher<MethodTree> IS_LIKELY_OVERRIDDEN =
-      allOf(
-          not(hasModifier(Modifier.FINAL)),
-          not(hasModifier(Modifier.PRIVATE)),
-          enclosingClass(hasModifier(Modifier.ABSTRACT)));
-
-  /** Instantiates a new {@link JUnitMethodDeclaration} instance. */
-  public JUnitMethodDeclaration() {}
+      ImmutableSet.of(Modifier.PRIVATE, Modifier.PROTECTED, Modifier.PUBLIC);
+  private static final Matcher<MethodTree> HAS_UNMODIFIABLE_SIGNATURE =
+      anyOf(
+          annotations(AT_LEAST_ONE, isType("java.lang.Override")),
+          allOf(
+              Matchers.not(hasModifier(Modifier.FINAL)),
+              Matchers.not(hasModifier(Modifier.PRIVATE)),
+              enclosingClass(hasModifier(Modifier.ABSTRACT))));
+  private static final MultiMatcher<MethodTree, AnnotationTree> TEST_METHOD =
+      annotations(
+          AT_LEAST_ONE,
+          anyOf(
+              isType("org.junit.jupiter.api.Test"),
+              hasMetaAnnotation("org.junit.jupiter.api.TestTemplate")));
+  private static final MultiMatcher<MethodTree, AnnotationTree> SETUP_OR_TEARDOWN_METHOD =
+      annotations(
+          AT_LEAST_ONE,
+          anyOf(
+              isType("org.junit.jupiter.api.AfterAll"),
+              isType("org.junit.jupiter.api.AfterEach"),
+              isType("org.junit.jupiter.api.BeforeAll"),
+              isType("org.junit.jupiter.api.BeforeEach")));
 
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
-    if (IS_LIKELY_OVERRIDDEN.matches(tree, state) || isOverride(tree, state)) {
+    if (HAS_UNMODIFIABLE_SIGNATURE.matches(tree, state)) {
       return Description.NO_MATCH;
     }
 
@@ -81,11 +103,10 @@ public final class JUnitMethodDeclaration extends BugChecker implements MethodTr
 
   private void suggestTestMethodRenameIfApplicable(
       MethodTree tree, SuggestedFix.Builder fixBuilder, VisitorState state) {
-    MethodSymbol symbol = ASTHelpers.getSymbol(tree);
-    tryCanonicalizeMethodName(symbol)
+    tryCanonicalizeMethodName(tree)
         .ifPresent(
             newName ->
-                ConflictDetection.findMethodRenameBlocker(symbol, newName, state)
+                findMethodRenameBlocker(newName, state)
                     .ifPresentOrElse(
                         blocker -> reportMethodRenameBlocker(tree, blocker, state),
                         () -> fixBuilder.merge(SuggestedFixes.renameMethod(tree, newName, state))));
@@ -101,8 +122,63 @@ public final class JUnitMethodDeclaration extends BugChecker implements MethodTr
             .build());
   }
 
-  private static Optional<String> tryCanonicalizeMethodName(MethodSymbol symbol) {
-    return Optional.of(symbol.getQualifiedName().toString())
+  /**
+   * If applicable, returns a human-readable argument against assigning the given name to an
+   * existing method.
+   *
+   * <p>This method implements imperfect heuristics. Things it currently does not consider include
+   * the following:
+   *
+   * <ul>
+   *   <li>Whether the rename would merely introduce a method overload, rather than clashing with an
+   *       existing method declaration.
+   *   <li>Whether the rename would cause a method in a superclass to be overridden.
+   *   <li>Whether the rename would in fact clash with a static import. (It could be that a static
+   *       import of the same name is only referenced from lexical scopes in which the method under
+   *       consideration cannot be referenced directly.)
+   * </ul>
+   */
+  private static Optional<String> findMethodRenameBlocker(String methodName, VisitorState state) {
+    if (isMethodInEnclosingClass(methodName, state)) {
+      return Optional.of(
+          String.format("a method named `%s` already exists in this class", methodName));
+    }
+
+    if (isSimpleNameStaticallyImported(methodName, state)) {
+      return Optional.of(String.format("`%s` is already statically imported", methodName));
+    }
+
+    if (isReservedKeyword(methodName)) {
+      return Optional.of(String.format("`%s` is a reserved keyword", methodName));
+    }
+
+    return Optional.empty();
+  }
+
+  private static boolean isMethodInEnclosingClass(String methodName, VisitorState state) {
+    return state.findEnclosing(ClassTree.class).getMembers().stream()
+        .filter(MethodTree.class::isInstance)
+        .map(MethodTree.class::cast)
+        .map(MethodTree::getName)
+        .map(Name::toString)
+        .anyMatch(methodName::equals);
+  }
+
+  private static boolean isSimpleNameStaticallyImported(String simpleName, VisitorState state) {
+    return state.getPath().getCompilationUnit().getImports().stream()
+        .filter(ImportTree::isStatic)
+        .map(ImportTree::getQualifiedIdentifier)
+        .map(tree -> getStaticImportSimpleName(tree, state))
+        .anyMatch(simpleName::contentEquals);
+  }
+
+  private static CharSequence getStaticImportSimpleName(Tree tree, VisitorState state) {
+    String source = SourceCode.treeToString(tree, state);
+    return source.subSequence(source.lastIndexOf('.') + 1, source.length());
+  }
+
+  private static Optional<String> tryCanonicalizeMethodName(MethodTree tree) {
+    return Optional.of(ASTHelpers.getSymbol(tree).getQualifiedName().toString())
         .filter(name -> name.startsWith(TEST_PREFIX))
         .map(name -> name.substring(TEST_PREFIX.length()))
         .filter(not(String::isEmpty))
@@ -110,9 +186,17 @@ public final class JUnitMethodDeclaration extends BugChecker implements MethodTr
         .filter(name -> !Character.isDigit(name.charAt(0)));
   }
 
-  private static boolean isOverride(MethodTree tree, VisitorState state) {
-    return ASTHelpers.streamSuperMethods(ASTHelpers.getSymbol(tree), state.getTypes())
-        .findAny()
-        .isPresent();
+  // XXX: Move to a `MoreMatchers` utility class.
+  private static Matcher<AnnotationTree> hasMetaAnnotation(String annotationClassName) {
+    TypePredicate typePredicate = hasAnnotation(annotationClassName);
+    return (tree, state) -> {
+      Symbol sym = ASTHelpers.getSymbol(tree);
+      return sym != null && typePredicate.apply(sym.type, state);
+    };
+  }
+
+  // XXX: Move to a `MoreTypePredicates` utility class.
+  private static TypePredicate hasAnnotation(String annotationClassName) {
+    return (type, state) -> ASTHelpers.hasAnnotation(type.tsym, annotationClassName, state);
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/LexicographicalAnnotationAttributeListing.java

@@ -40,9 +40,8 @@ import java.util.List;
 import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Stream;
-import org.jspecify.annotations.Nullable;
+import javax.annotation.Nullable;
 import tech.picnic.errorprone.bugpatterns.util.AnnotationAttributeMatcher;
-import tech.picnic.errorprone.bugpatterns.util.Flags;
 import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
@@ -83,7 +82,7 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
 
   private final AnnotationAttributeMatcher matcher;
 
-  /** Instantiates a default {@link LexicographicalAnnotationAttributeListing} instance. */
+  /** Instantiates the default {@link LexicographicalAnnotationAttributeListing}. */
   public LexicographicalAnnotationAttributeListing() {
     this(ErrorProneFlags.empty());
   }
@@ -185,15 +184,17 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
   private static ImmutableList<ImmutableList<String>> getStructure(ExpressionTree array) {
     ImmutableList.Builder<ImmutableList<String>> nodes = ImmutableList.builder();
 
-    new TreeScanner<@Nullable Void, @Nullable Void>() {
+    new TreeScanner<Void, Void>() {
+      @Nullable
       @Override
-      public @Nullable Void visitIdentifier(IdentifierTree node, @Nullable Void unused) {
+      public Void visitIdentifier(IdentifierTree node, @Nullable Void unused) {
         nodes.add(ImmutableList.of(node.getName().toString()));
         return super.visitIdentifier(node, unused);
       }
 
+      @Nullable
       @Override
-      public @Nullable Void visitLiteral(LiteralTree node, @Nullable Void unused) {
+      public Void visitLiteral(LiteralTree node, @Nullable Void unused) {
         Object value = ASTHelpers.constValue(node);
         nodes.add(
             value instanceof String
@@ -203,8 +204,9 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
         return super.visitLiteral(node, unused);
       }
 
+      @Nullable
       @Override
-      public @Nullable Void visitPrimitiveType(PrimitiveTypeTree node, @Nullable Void unused) {
+      public Void visitPrimitiveType(PrimitiveTypeTree node, @Nullable Void unused) {
         nodes.add(ImmutableList.of(node.getPrimitiveTypeKind().toString()));
         return super.visitPrimitiveType(node, unused);
       }
@@ -221,7 +223,7 @@ public final class LexicographicalAnnotationAttributeListing extends BugChecker
 
   private static ImmutableList<String> excludedAnnotations(ErrorProneFlags flags) {
     Set<String> exclusions = new HashSet<>();
-    exclusions.addAll(Flags.getList(flags, EXCLUDED_ANNOTATIONS_FLAG));
+    flags.getList(EXCLUDED_ANNOTATIONS_FLAG).ifPresent(exclusions::addAll);
     exclusions.addAll(BLACKLISTED_ANNOTATIONS);
     return ImmutableList.copyOf(exclusions);
   }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/LexicographicalAnnotationListing.java

@@ -4,13 +4,10 @@ import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.STYLE;
-import static com.sun.tools.javac.code.TypeAnnotations.AnnotationType.DECLARATION;
-import static com.sun.tools.javac.code.TypeAnnotations.AnnotationType.TYPE;
 import static java.util.Comparator.comparing;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
-import com.google.common.base.VerifyException;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Streams;
 import com.google.errorprone.BugPattern;
@@ -20,14 +17,10 @@ import com.google.errorprone.bugpatterns.BugChecker.MethodTreeMatcher;
 import com.google.errorprone.fixes.Fix;
 import com.google.errorprone.fixes.SuggestedFix;
 import com.google.errorprone.matchers.Description;
-import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.MethodTree;
-import com.sun.tools.javac.code.Symbol;
-import com.sun.tools.javac.code.TypeAnnotations.AnnotationType;
-import java.util.Comparator;
 import java.util.List;
-import org.jspecify.annotations.Nullable;
+import java.util.Optional;
 import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
@@ -46,12 +39,6 @@ import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 public final class LexicographicalAnnotationListing extends BugChecker
     implements MethodTreeMatcher {
   private static final long serialVersionUID = 1L;
-  private static final Comparator<@Nullable AnnotationType> BY_ANNOTATION_TYPE =
-      (a, b) ->
-          (a == null || a == DECLARATION) && b == TYPE ? -1 : a == TYPE && b == DECLARATION ? 1 : 0;
-
-  /** Instantiates a new {@link LexicographicalAnnotationListing} instance. */
-  public LexicographicalAnnotationListing() {}
 
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
@@ -60,29 +47,26 @@ public final class LexicographicalAnnotationListing extends BugChecker
       return Description.NO_MATCH;
     }
 
-    ImmutableList<? extends AnnotationTree> sortedAnnotations =
-        sort(originalOrdering, ASTHelpers.getSymbol(tree), state);
+    ImmutableList<? extends AnnotationTree> sortedAnnotations = sort(originalOrdering, state);
     if (originalOrdering.equals(sortedAnnotations)) {
       return Description.NO_MATCH;
     }
 
-    return describeMatch(
-        originalOrdering.get(0), fixOrdering(originalOrdering, sortedAnnotations, state));
+    Optional<Fix> fix = tryFixOrdering(originalOrdering, sortedAnnotations, state);
+
+    Description.Builder description = buildDescription(originalOrdering.get(0));
+    fix.ifPresent(description::addFix);
+    return description.build();
   }
 
   private static ImmutableList<? extends AnnotationTree> sort(
-      List<? extends AnnotationTree> annotations, Symbol symbol, VisitorState state) {
+      List<? extends AnnotationTree> annotations, VisitorState state) {
     return annotations.stream()
-        .sorted(
-            comparing(
-                    (AnnotationTree annotation) ->
-                        ASTHelpers.getAnnotationType(annotation, symbol, state),
-                    BY_ANNOTATION_TYPE)
-                .thenComparing(annotation -> SourceCode.treeToString(annotation, state)))
+        .sorted(comparing(annotation -> SourceCode.treeToString(annotation, state)))
         .collect(toImmutableList());
   }
 
-  private static Fix fixOrdering(
+  private static Optional<Fix> tryFixOrdering(
       List<? extends AnnotationTree> originalAnnotations,
       ImmutableList<? extends AnnotationTree> sortedAnnotations,
       VisitorState state) {
@@ -93,7 +77,6 @@ public final class LexicographicalAnnotationListing extends BugChecker
                 SuggestedFix.builder()
                     .replace(original, SourceCode.treeToString(replacement, state)))
         .reduce(SuggestedFix.Builder::merge)
-        .map(SuggestedFix.Builder::build)
-        .orElseThrow(() -> new VerifyException("No annotations were provided"));
+        .map(SuggestedFix.Builder::build);
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MethodReferenceUsage.java

@@ -37,8 +37,6 @@ import javax.lang.model.element.Name;
 
 /**
  * A {@link BugChecker} that flags lambda expressions that can be replaced with method references.
- *
- * @see IsInstanceLambdaUsage
  */
 // XXX: Other custom expressions we could rewrite:
 // - `a -> "str" + a` to `"str"::concat`. But only if `str` is provably non-null.
@@ -52,9 +50,6 @@ import javax.lang.model.element.Name;
 // `not(some::reference)`.
 // XXX: This check is extremely inefficient due to its reliance on `SuggestedFixes.compilesWithFix`.
 // Palantir's `LambdaMethodReference` check seems to suffer a similar issue at this time.
-// XXX: Expressions of the form `i -> SomeType.class.isInstance(i)` are not replaced; fix that using
-// a suitable generalization.
-// XXX: Consider folding the `IsInstanceLambdaUsage` check into this class.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Prefer method references over lambda expressions",
@@ -65,9 +60,6 @@ import javax.lang.model.element.Name;
 public final class MethodReferenceUsage extends BugChecker implements LambdaExpressionTreeMatcher {
   private static final long serialVersionUID = 1L;
 
-  /** Instantiates a new {@link MethodReferenceUsage} instance. */
-  public MethodReferenceUsage() {}
-
   @Override
   public Description matchLambdaExpression(LambdaExpressionTree tree, VisitorState state) {
     /*
@@ -130,7 +122,7 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
           return Optional.empty();
         }
         Symbol sym = ASTHelpers.getSymbol(methodSelect);
-        if (!ASTHelpers.isStatic(sym)) {
+        if (!sym.isStatic()) {
           return constructFix(lambdaExpr, "this", methodSelect);
         }
         return constructFix(lambdaExpr, sym.owner, methodSelect);
@@ -200,7 +192,7 @@ public final class MethodReferenceUsage extends BugChecker implements LambdaExpr
     Name sName = target.getSimpleName();
     Optional<SuggestedFix.Builder> fix = constructFix(lambdaExpr, sName, methodName);
 
-    if (!"java.lang".equals(ASTHelpers.enclosingPackage(target).toString())) {
+    if (!"java.lang".equals(target.packge().toString())) {
       Name fqName = target.getQualifiedName();
       if (!sName.equals(fqName)) {
         return fix.map(b -> b.addImport(fqName.toString()));

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MissingRefasterAnnotation.java

@@ -40,9 +40,6 @@ public final class MissingRefasterAnnotation extends BugChecker implements Class
               isType("com.google.errorprone.refaster.annotation.BeforeTemplate"),
               isType("com.google.errorprone.refaster.annotation.AfterTemplate")));
 
-  /** Instantiates a new {@link MissingRefasterAnnotation} instance. */
-  public MissingRefasterAnnotation() {}
-
   @Override
   public Description matchClass(ClassTree tree, VisitorState state) {
     long methodTypes =

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/MockitoStubbing.java

@@ -36,9 +36,6 @@ public final class MockitoStubbing extends BugChecker implements MethodInvocatio
   private static final Matcher<ExpressionTree> MOCKITO_EQ_METHOD =
       staticMethod().onClass("org.mockito.ArgumentMatchers").named("eq");
 
-  /** Instantiates a new {@link MockitoStubbing} instance. */
-  public MockitoStubbing() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     List<? extends ExpressionTree> arguments = tree.getArguments();

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NestedOptionals.java

@@ -4,11 +4,9 @@ import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.generic;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.raw;
-import static tech.picnic.errorprone.bugpatterns.util.MoreTypes.subOf;
 
 import com.google.auto.service.AutoService;
+import com.google.common.collect.Iterables;
 import com.google.errorprone.BugPattern;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker;
@@ -18,7 +16,9 @@ import com.google.errorprone.suppliers.Supplier;
 import com.google.errorprone.suppliers.Suppliers;
 import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.MethodInvocationTree;
+import com.sun.source.tree.Tree;
 import com.sun.tools.javac.code.Type;
+import com.sun.tools.javac.util.List;
 import java.util.Optional;
 
 /** A {@link BugChecker} that flags nesting of {@link Optional Optionals}. */
@@ -33,19 +33,21 @@ import java.util.Optional;
 public final class NestedOptionals extends BugChecker implements MethodInvocationTreeMatcher {
   private static final long serialVersionUID = 1L;
   private static final Supplier<Type> OPTIONAL = Suppliers.typeFromClass(Optional.class);
-  private static final Supplier<Type> OPTIONAL_OF_OPTIONAL =
-      VisitorState.memoize(generic(OPTIONAL, subOf(raw(OPTIONAL))));
-
-  /** Instantiates a new {@link NestedOptionals} instance. */
-  public NestedOptionals() {}
 
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    Type type = OPTIONAL_OF_OPTIONAL.get(state);
-    if (type == null || !state.getTypes().isSubtype(ASTHelpers.getType(tree), type)) {
-      return Description.NO_MATCH;
+    return isOptionalOfOptional(tree, state) ? describeMatch(tree) : Description.NO_MATCH;
+  }
+
+  private static boolean isOptionalOfOptional(Tree tree, VisitorState state) {
+    Type optionalType = OPTIONAL.get(state);
+    Type type = ASTHelpers.getType(tree);
+    if (!ASTHelpers.isSubtype(type, optionalType, state)) {
+      return false;
     }
 
-    return describeMatch(tree);
+    List<Type> typeArguments = type.getTypeArguments();
+    return !typeArguments.isEmpty()
+        && ASTHelpers.isSubtype(Iterables.getOnlyElement(typeArguments), optionalType, state);
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/NonEmptyMono.java

@@ -76,9 +76,6 @@ public final class NonEmptyMono extends BugChecker implements MethodInvocationTr
               .onDescendantOf("reactor.core.publisher.Mono")
               .namedAnyOf("defaultIfEmpty", "hasElement", "single"));
 
-  /** Instantiates a new {@link NonEmptyMono} instance. */
-  public NonEmptyMono() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (!MONO_SIZE_CHECK.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/PrimitiveComparison.java

@@ -70,9 +70,6 @@ public final class PrimitiveComparison extends BugChecker implements MethodInvoc
               .named("thenComparing")
               .withParameters(Function.class.getName()));
 
-  /** Instantiates a new {@link PrimitiveComparison} instance. */
-  public PrimitiveComparison() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     boolean isStatic = STATIC_COMPARISON_METHOD.matches(tree, state);

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RedundantStringConversion.java

@@ -49,7 +49,6 @@ import java.util.Locale;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.stream.Stream;
-import tech.picnic.errorprone.bugpatterns.util.Flags;
 import tech.picnic.errorprone.bugpatterns.util.MethodMatcherFactory;
 import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
@@ -64,8 +63,9 @@ import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 public final class RedundantStringConversion extends BugChecker
     implements BinaryTreeMatcher, CompoundAssignmentTreeMatcher, MethodInvocationTreeMatcher {
   private static final long serialVersionUID = 1L;
+  private static final String FLAG_PREFIX = "RedundantStringConversion:";
   private static final String EXTRA_STRING_CONVERSION_METHODS_FLAG =
-      "RedundantStringConversion:ExtraConversionMethods";
+      FLAG_PREFIX + "ExtraConversionMethods";
 
   @SuppressWarnings("UnnecessaryLambda")
   private static final Matcher<ExpressionTree> ANY_EXPR = (t, s) -> true;
@@ -141,7 +141,7 @@ public final class RedundantStringConversion extends BugChecker
 
   private final Matcher<MethodInvocationTree> conversionMethodMatcher;
 
-  /** Instantiates a default {@link RedundantStringConversion} instance. */
+  /** Instantiates the default {@link RedundantStringConversion}. */
   public RedundantStringConversion() {
     this(ErrorProneFlags.empty());
   }
@@ -374,9 +374,10 @@ public final class RedundantStringConversion extends BugChecker
       ErrorProneFlags flags) {
     // XXX: ErrorProneFlags#getList splits by comma, but method signatures may also contain commas.
     // For this class methods accepting more than one argument are not valid, but still: not nice.
-    return anyOf(
-        WELL_KNOWN_STRING_CONVERSION_METHODS,
-        new MethodMatcherFactory()
-            .create(Flags.getList(flags, EXTRA_STRING_CONVERSION_METHODS_FLAG)));
+    return flags
+        .getList(EXTRA_STRING_CONVERSION_METHODS_FLAG)
+        .map(new MethodMatcherFactory()::create)
+        .map(m -> anyOf(WELL_KNOWN_STRING_CONVERSION_METHODS, m))
+        .orElse(WELL_KNOWN_STRING_CONVERSION_METHODS);
   }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RefasterAnyOfUsage.java

@@ -37,9 +37,6 @@ public final class RefasterAnyOfUsage extends BugChecker implements MethodInvoca
   private static final Matcher<ExpressionTree> REFASTER_ANY_OF =
       staticMethod().onClass(Refaster.class.getName()).named("anyOf");
 
-  /** Instantiates a new {@link RefasterAnyOfUsage} instance. */
-  public RefasterAnyOfUsage() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (REFASTER_ANY_OF.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RefasterRuleModifiers.java

@@ -29,7 +29,7 @@ import java.util.Set;
 import javax.lang.model.element.Modifier;
 
 /**
- * A {@link BugChecker} that suggests a canonical set of modifiers for Refaster class and method
+ * A {@link BugChecker} which suggests a canonical set of modifiers for Refaster class and method
  * definitions.
  */
 @AutoService(BugChecker.class)
@@ -48,9 +48,6 @@ public final class RefasterRuleModifiers extends BugChecker
   private static final Matcher<Tree> REFASTER_METHOD =
       anyOf(BEFORE_TEMPLATE_METHOD, AFTER_TEMPLATE_METHOD, PLACEHOLDER_METHOD);
 
-  /** Instantiates a new {@link RefasterRuleModifiers} instance. */
-  public RefasterRuleModifiers() {}
-
   @Override
   public Description matchClass(ClassTree tree, VisitorState state) {
     if (!hasMatchingMember(tree, BEFORE_TEMPLATE_METHOD, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RequestMappingAnnotation.java

@@ -83,9 +83,6 @@ public final class RequestMappingAnnotation extends BugChecker implements Method
                   isSameType("org.springframework.web.util.UriBuilder"),
                   isSameType("org.springframework.web.util.UriComponentsBuilder"))));
 
-  /** Instantiates a new {@link RequestMappingAnnotation} instance. */
-  public RequestMappingAnnotation() {}
-
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
     // XXX: Auto-add `@RequestParam` where applicable.

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/RequestParamType.java

@@ -1,6 +1,5 @@
 package tech.picnic.errorprone.bugpatterns;
 
-import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
 import static com.google.errorprone.BugPattern.StandardTags.LIKELY_ERROR;
@@ -10,72 +9,38 @@ import static com.google.errorprone.matchers.Matchers.annotations;
 import static com.google.errorprone.matchers.Matchers.anyOf;
 import static com.google.errorprone.matchers.Matchers.isSubtypeOf;
 import static com.google.errorprone.matchers.Matchers.isType;
-import static com.google.errorprone.matchers.Matchers.not;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.collect.ImmutableCollection;
-import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.errorprone.BugPattern;
-import com.google.errorprone.ErrorProneFlags;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker;
 import com.google.errorprone.bugpatterns.BugChecker.VariableTreeMatcher;
 import com.google.errorprone.matchers.Description;
 import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.suppliers.Suppliers;
-import com.sun.source.tree.Tree;
 import com.sun.source.tree.VariableTree;
-import tech.picnic.errorprone.bugpatterns.util.Flags;
 
 /** A {@link BugChecker} that flags {@code @RequestParam} parameters with an unsupported type. */
 @AutoService(BugChecker.class)
 @BugPattern(
-    summary =
-        "By default, `@RequestParam` does not support `ImmutableCollection` and `ImmutableMap` subtypes",
+    summary = "`@RequestParam` does not support `ImmutableCollection` and `ImmutableMap` subtypes",
     link = BUG_PATTERNS_BASE_URL + "RequestParamType",
     linkType = CUSTOM,
     severity = ERROR,
     tags = LIKELY_ERROR)
 public final class RequestParamType extends BugChecker implements VariableTreeMatcher {
   private static final long serialVersionUID = 1L;
-  private static final String SUPPORTED_CUSTOM_TYPES_FLAG = "RequestParamType:SupportedCustomTypes";
-
-  private final Matcher<VariableTree> hasUnsupportedRequestParamType;
-
-  /** Instantiates a default {@link RequestParamType} instance. */
-  public RequestParamType() {
-    this(ErrorProneFlags.empty());
-  }
-
-  /**
-   * Instantiates a customized {@link RequestParamType} instance.
-   *
-   * @param flags Any provided command line flags.
-   */
-  public RequestParamType(ErrorProneFlags flags) {
-    hasUnsupportedRequestParamType = hasUnsupportedRequestParamType(flags);
-  }
+  private static final Matcher<VariableTree> HAS_UNSUPPORTED_REQUEST_PARAM =
+      allOf(
+          annotations(AT_LEAST_ONE, isType("org.springframework.web.bind.annotation.RequestParam")),
+          anyOf(isSubtypeOf(ImmutableCollection.class), isSubtypeOf(ImmutableMap.class)));
 
   @Override
   public Description matchVariable(VariableTree tree, VisitorState state) {
-    return hasUnsupportedRequestParamType.matches(tree, state)
+    return HAS_UNSUPPORTED_REQUEST_PARAM.matches(tree, state)
         ? describeMatch(tree)
         : Description.NO_MATCH;
   }
-
-  private static Matcher<VariableTree> hasUnsupportedRequestParamType(ErrorProneFlags flags) {
-    return allOf(
-        annotations(AT_LEAST_ONE, isType("org.springframework.web.bind.annotation.RequestParam")),
-        anyOf(isSubtypeOf(ImmutableCollection.class), isSubtypeOf(ImmutableMap.class)),
-        not(isSubtypeOfAny(Flags.getList(flags, SUPPORTED_CUSTOM_TYPES_FLAG))));
-  }
-
-  private static Matcher<Tree> isSubtypeOfAny(ImmutableList<String> inclusions) {
-    return anyOf(
-        inclusions.stream()
-            .map(inclusion -> isSubtypeOf(Suppliers.typeFromString(inclusion)))
-            .collect(toImmutableList()));
-  }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/ScheduledTransactionTrace.java

@@ -26,7 +26,6 @@ import com.google.errorprone.util.ASTHelpers;
 import com.sun.source.tree.AnnotationTree;
 import com.sun.source.tree.MethodTree;
 import com.sun.source.tree.Tree;
-import tech.picnic.errorprone.bugpatterns.util.ThirdPartyLibrary;
 
 /**
  * A {@link BugChecker} that flags methods with Spring's {@code @Scheduled} annotation that lack New
@@ -47,13 +46,9 @@ public final class ScheduledTransactionTrace extends BugChecker implements Metho
   private static final MultiMatcher<Tree, AnnotationTree> TRACE_ANNOTATION =
       annotations(AT_LEAST_ONE, isType(TRACE_ANNOTATION_FQCN));
 
-  /** Instantiates a new {@link ScheduledTransactionTrace} instance. */
-  public ScheduledTransactionTrace() {}
-
   @Override
   public Description matchMethod(MethodTree tree, VisitorState state) {
-    if (!ThirdPartyLibrary.NEW_RELIC_AGENT_API.isIntroductionAllowed(state)
-        || !IS_SCHEDULED.matches(tree, state)) {
+    if (!IS_SCHEDULED.matches(tree, state)) {
       return Description.NO_MATCH;
     }
 

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/Slf4jLogStatement.java

@@ -48,9 +48,6 @@ public final class Slf4jLogStatement extends BugChecker implements MethodInvocat
           .onDescendantOf("org.slf4j.Logger")
           .namedAnyOf("trace", "debug", "info", "warn", "error");
 
-  /** Instantiates a new {@link Slf4jLogStatement} instance. */
-  public Slf4jLogStatement() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (!SLF4J_LOGGER_INVOCATION.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/SpringMvcAnnotation.java

@@ -57,9 +57,6 @@ public final class SpringMvcAnnotation extends BugChecker implements AnnotationT
           .put("PUT", "PutMapping")
           .build();
 
-  /** Instantiates a new {@link SpringMvcAnnotation} instance. */
-  public SpringMvcAnnotation() {}
-
   @Override
   public Description matchAnnotation(AnnotationTree tree, VisitorState state) {
     // XXX: We could remove the `@RequestMapping` import if not other usages remain.

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/StaticImport.java

@@ -101,8 +101,7 @@ public final class StaticImport extends BugChecker implements MemberSelectTreeMa
           "org.springframework.http.HttpMethod",
           "org.springframework.http.MediaType",
           "org.testng.Assert",
-          "reactor.function.TupleUtils",
-          "tech.picnic.errorprone.bugpatterns.util.MoreTypes");
+          "reactor.function.TupleUtils");
 
   /** Type members that should be statically imported. */
   @VisibleForTesting
@@ -191,9 +190,6 @@ public final class StaticImport extends BugChecker implements MemberSelectTreeMa
           "of",
           "valueOf");
 
-  /** Instantiates a new {@link StaticImport} instance. */
-  public StaticImport() {}
-
   @Override
   public Description matchMemberSelect(MemberSelectTree tree, VisitorState state) {
     if (!isCandidateContext(state) || !isCandidate(tree)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/StringCaseLocaleUsage.java

@@ -1,89 +0,0 @@
-package tech.picnic.errorprone.bugpatterns;
-
-import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
-import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
-import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
-import static com.google.errorprone.matchers.method.MethodMatchers.instanceMethod;
-import static com.sun.tools.javac.parser.Tokens.TokenKind.RPAREN;
-import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
-
-import com.google.auto.service.AutoService;
-import com.google.common.collect.Streams;
-import com.google.errorprone.BugPattern;
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
-import com.google.errorprone.fixes.Fix;
-import com.google.errorprone.fixes.SuggestedFix;
-import com.google.errorprone.matchers.Description;
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.util.ASTHelpers;
-import com.google.errorprone.util.ErrorProneTokens;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.MethodInvocationTree;
-import com.sun.tools.javac.util.Position;
-import tech.picnic.errorprone.bugpatterns.util.SourceCode;
-
-/**
- * A {@link BugChecker} that flags calls to {@link String#toLowerCase()} and {@link
- * String#toUpperCase()}, as these methods implicitly rely on the environment's default locale.
- */
-// XXX: Also flag `String::toLowerCase` and `String::toUpperCase` method references. For these cases
-// the suggested fix should introduce a lambda expression with a parameter of which the name does
-// not coincide with the name of an existing variable name. Such functionality should likely be
-// introduced in a utility class.
-@AutoService(BugChecker.class)
-@BugPattern(
-    summary = "Specify a `Locale` when calling `String#to{Lower,Upper}Case`",
-    link = BUG_PATTERNS_BASE_URL + "StringCaseLocaleUsage",
-    linkType = CUSTOM,
-    severity = WARNING,
-    tags = FRAGILE_CODE)
-public final class StringCaseLocaleUsage extends BugChecker implements MethodInvocationTreeMatcher {
-  private static final long serialVersionUID = 1L;
-  private static final Matcher<ExpressionTree> DEFAULT_LOCALE_CASE_CONVERSION =
-      instanceMethod()
-          .onExactClass(String.class.getName())
-          .namedAnyOf("toLowerCase", "toUpperCase")
-          .withNoParameters();
-
-  /** Instantiates a new {@link StringCaseLocaleUsage} instance. */
-  public StringCaseLocaleUsage() {}
-
-  @Override
-  public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
-    if (!DEFAULT_LOCALE_CASE_CONVERSION.matches(tree, state)) {
-      return Description.NO_MATCH;
-    }
-
-    int closingParenPosition = getClosingParenPosition(tree, state);
-    if (closingParenPosition == Position.NOPOS) {
-      return describeMatch(tree);
-    }
-
-    return buildDescription(tree)
-        .addFix(suggestLocale(closingParenPosition, "Locale.ROOT"))
-        .addFix(suggestLocale(closingParenPosition, "Locale.getDefault()"))
-        .build();
-  }
-
-  private static Fix suggestLocale(int insertPosition, String locale) {
-    return SuggestedFix.builder()
-        .addImport("java.util.Locale")
-        .replace(insertPosition, insertPosition, locale)
-        .build();
-  }
-
-  private static int getClosingParenPosition(MethodInvocationTree tree, VisitorState state) {
-    int startPosition = ASTHelpers.getStartPosition(tree);
-    if (startPosition == Position.NOPOS) {
-      return Position.NOPOS;
-    }
-
-    return Streams.findLast(
-            ErrorProneTokens.getTokens(SourceCode.treeToString(tree, state), state.context).stream()
-                .filter(t -> t.kind() == RPAREN))
-        .map(token -> startPosition + token.pos())
-        .orElse(Position.NOPOS);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/StringJoin.java

@@ -1,10 +1,9 @@
 package tech.picnic.errorprone.bugpatterns;
 
-import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
+import static com.google.errorprone.BugPattern.LinkType.NONE;
 import static com.google.errorprone.BugPattern.SeverityLevel.SUGGESTION;
 import static com.google.errorprone.BugPattern.StandardTags.SIMPLIFICATION;
 import static com.google.errorprone.matchers.method.MethodMatchers.staticMethod;
-import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
 import com.google.common.base.Splitter;
@@ -27,12 +26,12 @@ import com.sun.tools.javac.util.Convert;
 import java.util.Formattable;
 import java.util.Iterator;
 import java.util.List;
-import org.jspecify.annotations.Nullable;
+import javax.annotation.Nullable;
 import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 
 /**
- * A {@link BugChecker} that flags {@link String#format(String, Object...)} invocations which can be
- * replaced with a {@link String#join(CharSequence, CharSequence...)} or even a {@link
+ * A {@link BugChecker} which flags {@link String#format(String, Object...)} invocations which can
+ * be replaced with a {@link String#join(CharSequence, CharSequence...)} or even a {@link
  * String#valueOf} invocation.
  */
 // XXX: What about `v1 + "sep" + v2` and similar expressions? Do we want to rewrite those to
@@ -41,8 +40,7 @@ import tech.picnic.errorprone.bugpatterns.util.SourceCode;
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "Prefer `String#join` over `String#format`",
-    link = BUG_PATTERNS_BASE_URL + "StringJoin",
-    linkType = CUSTOM,
+    linkType = NONE,
     severity = SUGGESTION,
     tags = SIMPLIFICATION)
 public final class StringJoin extends BugChecker implements MethodInvocationTreeMatcher {
@@ -54,9 +52,6 @@ public final class StringJoin extends BugChecker implements MethodInvocationTree
       Suppliers.typeFromClass(CharSequence.class);
   private static final Supplier<Type> FORMATTABLE_TYPE = Suppliers.typeFromClass(Formattable.class);
 
-  /** Instantiates a new {@link StringJoin} instance. */
-  public StringJoin() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     if (!STRING_FORMAT_INVOCATION.matches(tree, state)) {

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/TimeZoneUsage.java

@@ -26,9 +26,6 @@ import java.time.Instant;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
-import java.time.OffsetDateTime;
-import java.time.OffsetTime;
-import java.time.ZonedDateTime;
 
 /** A {@link BugChecker} that flags illegal time-zone related operations. */
 @AutoService(BugChecker.class)
@@ -61,16 +58,10 @@ public final class TimeZoneUsage extends BugChecker implements MethodInvocationT
               .onClassAny(
                   LocalDate.class.getName(),
                   LocalDateTime.class.getName(),
-                  LocalTime.class.getName(),
-                  OffsetDateTime.class.getName(),
-                  OffsetTime.class.getName(),
-                  ZonedDateTime.class.getName())
+                  LocalTime.class.getName())
               .named("now"),
           staticMethod().onClassAny(Instant.class.getName()).named("now").withNoParameters());
 
-  /** Instantiates a new {@link TimeZoneUsage} instance. */
-  public TimeZoneUsage() {}
-
   @Override
   public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
     return BANNED_TIME_METHOD.matches(tree, state)

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/package-info.java

@@ -1,4 +1,4 @@
 /** Picnic Error Prone Contrib checks. */
 @com.google.errorprone.annotations.CheckReturnValue
-@org.jspecify.annotations.NullMarked
+@javax.annotation.ParametersAreNonnullByDefault
 package tech.picnic.errorprone.bugpatterns;

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/ConflictDetection.java

@@ -1,75 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import static tech.picnic.errorprone.bugpatterns.util.JavaKeywords.isValidIdentifier;
-
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.ImportTree;
-import com.sun.source.tree.Tree;
-import com.sun.tools.javac.code.Symbol.MethodSymbol;
-import com.sun.tools.javac.code.Type;
-import java.util.Optional;
-
-/** A set of helper methods for detecting conflicts that would be caused when applying fixes. */
-public final class ConflictDetection {
-  private ConflictDetection() {}
-
-  /**
-   * If applicable, returns a human-readable argument against assigning the given name to an
-   * existing method.
-   *
-   * <p>This method implements imperfect heuristics. Things it currently does not consider include
-   * the following:
-   *
-   * <ul>
-   *   <li>Whether the rename would merely introduce a method overload, rather than clashing with an
-   *       existing method declaration in its class or a supertype.
-   *   <li>Whether the rename would in fact clash with a static import. (It could be that a static
-   *       import of the same name is only referenced from lexical scopes in which the method under
-   *       consideration cannot be referenced directly.)
-   * </ul>
-   *
-   * @param method The method considered for renaming.
-   * @param newName The newly proposed name for the method.
-   * @param state The {@link VisitorState} to use when searching for blockers.
-   * @return A human-readable argument against assigning the proposed name to the given method, or
-   *     {@link Optional#empty()} if no blocker was found.
-   */
-  public static Optional<String> findMethodRenameBlocker(
-      MethodSymbol method, String newName, VisitorState state) {
-    if (isExistingMethodName(method.owner.type, newName, state)) {
-      return Optional.of(
-          String.format(
-              "a method named `%s` is already defined in this class or a supertype", newName));
-    }
-
-    if (isSimpleNameStaticallyImported(newName, state)) {
-      return Optional.of(String.format("`%s` is already statically imported", newName));
-    }
-
-    if (!isValidIdentifier(newName)) {
-      return Optional.of(String.format("`%s` is not a valid identifier", newName));
-    }
-
-    return Optional.empty();
-  }
-
-  private static boolean isExistingMethodName(Type clazz, String name, VisitorState state) {
-    return ASTHelpers.matchingMethods(state.getName(name), method -> true, clazz, state.getTypes())
-        .findAny()
-        .isPresent();
-  }
-
-  private static boolean isSimpleNameStaticallyImported(String simpleName, VisitorState state) {
-    return state.getPath().getCompilationUnit().getImports().stream()
-        .filter(ImportTree::isStatic)
-        .map(ImportTree::getQualifiedIdentifier)
-        .map(tree -> getStaticImportSimpleName(tree, state))
-        .anyMatch(simpleName::contentEquals);
-  }
-
-  private static CharSequence getStaticImportSimpleName(Tree tree, VisitorState state) {
-    String source = SourceCode.treeToString(tree, state);
-    return source.subSequence(source.lastIndexOf('.') + 1, source.length());
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/Flags.java

@@ -1,25 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.ErrorProneFlags;
-
-/** Helper methods for working with {@link ErrorProneFlags}. */
-public final class Flags {
-  private Flags() {}
-
-  /**
-   * Returns the list of (comma-separated) arguments passed using the given Error Prone flag.
-   *
-   * @param errorProneFlags The full set of flags provided.
-   * @param name The name of the flag of interest.
-   * @return A non-{@code null} list of provided arguments; this list is empty if the flag was not
-   *     provided, or if the flag's value is the empty string.
-   */
-  public static ImmutableList<String> getList(ErrorProneFlags errorProneFlags, String name) {
-    return errorProneFlags
-        .getList(name)
-        .map(ImmutableList::copyOf)
-        .filter(flags -> !flags.equals(ImmutableList.of("")))
-        .orElseGet(ImmutableList::of);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/JavaKeywords.java

@@ -4,19 +4,7 @@ import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
 
 /** Utility class that can be used to identify reserved keywords of the Java language. */
-// XXX: This class is no longer only about keywords. Consider changing its name and class-level
-// documentation.
 public final class JavaKeywords {
-  /**
-   * Enumeration of boolean and null literals.
-   *
-   * @see <a href="https://docs.oracle.com/javase/specs/jls/se17/html/jls-3.html#jls-3.10.3">JDK 17
-   *     JLS section 3.10.3: Boolean Literals</a>
-   * @see <a href="https://docs.oracle.com/javase/specs/jls/se17/html/jls-3.html#jls-3.10.8">JDK 17
-   *     JLS section 3.10.8: The Null Literal</a>
-   */
-  private static final ImmutableSet<String> BOOLEAN_AND_NULL_LITERALS =
-      ImmutableSet.of("true", "false", "null");
   /**
    * List of all reserved keywords in the Java language.
    *
@@ -76,6 +64,7 @@ public final class JavaKeywords {
           "void",
           "volatile",
           "while");
+
   /**
    * List of all contextual keywords in the Java language.
    *
@@ -100,28 +89,13 @@ public final class JavaKeywords {
           "var",
           "with",
           "yield");
+
   /** List of all keywords in the Java language. */
   private static final ImmutableSet<String> ALL_KEYWORDS =
       Sets.union(RESERVED_KEYWORDS, CONTEXTUAL_KEYWORDS).immutableCopy();
 
   private JavaKeywords() {}
 
-  /**
-   * Tells whether the given string is a valid identifier in the Java language.
-   *
-   * @param str The string of interest.
-   * @return {@code true} if the given string is a valid identifier in the Java language.
-   * @see <a href="https://docs.oracle.com/javase/specs/jls/se17/html/jls-3.html#jls-3.8">JDK 17 JLS
-   *     section 3.8: Identifiers</a>
-   */
-  public static boolean isValidIdentifier(String str) {
-    return !str.isEmpty()
-        && !isReservedKeyword(str)
-        && !BOOLEAN_AND_NULL_LITERALS.contains(str)
-        && Character.isJavaIdentifierStart(str.codePointAt(0))
-        && str.codePoints().skip(1).allMatch(Character::isUnicodeIdentifierPart);
-  }
-
   /**
    * Tells whether the given string is a reserved keyword in the Java language.
    *

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MethodMatcherFactory.java

@@ -21,9 +21,6 @@ public final class MethodMatcherFactory {
   private static final Pattern METHOD_SIGNATURE =
       Pattern.compile("([^\\s#(,)]+)#([^\\s#(,)]+)\\(((?:[^\\s#(,)]+(?:,[^\\s#(,)]+)*)?)\\)");
 
-  /** Instantiates a new {@link MethodMatcherFactory} instance. */
-  public MethodMatcherFactory() {}
-
   /**
    * Creates a {@link Matcher} of methods with any of the given signatures.
    *

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreASTHelpers.java

@@ -1,49 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.collect.ImmutableList.toImmutableList;
-
-import com.google.common.collect.ImmutableList;
-import com.google.errorprone.VisitorState;
-import com.sun.source.tree.ClassTree;
-import com.sun.source.tree.MethodTree;
-
-/**
- * A collection of helper methods for working with the AST.
- *
- * <p>These methods are additions to the ones found in {@link
- * com.google.errorprone.util.ASTHelpers}.
- */
-public final class MoreASTHelpers {
-  private MoreASTHelpers() {}
-
-  /**
-   * Finds methods with the specified name in given the {@link VisitorState}'s current enclosing
-   * class.
-   *
-   * @param methodName The method name to search for.
-   * @param state The {@link VisitorState} from which to derive the enclosing class of interest.
-   * @return The {@link MethodTree}s of the methods with the given name in the enclosing class.
-   */
-  public static ImmutableList<MethodTree> findMethods(CharSequence methodName, VisitorState state) {
-    ClassTree clazz = state.findEnclosing(ClassTree.class);
-    checkArgument(clazz != null, "Visited node is not enclosed by a class");
-    return clazz.getMembers().stream()
-        .filter(MethodTree.class::isInstance)
-        .map(MethodTree.class::cast)
-        .filter(method -> method.getName().contentEquals(methodName))
-        .collect(toImmutableList());
-  }
-
-  /**
-   * Determines whether there are any methods with the specified name in given the {@link
-   * VisitorState}'s current enclosing class.
-   *
-   * @param methodName The method name to search for.
-   * @param state The {@link VisitorState} from which to derive the enclosing class of interest.
-   * @return Whether there are any methods with the given name in the enclosing class.
-   */
-  public static boolean methodExistsInEnclosingClass(CharSequence methodName, VisitorState state) {
-    return !findMethods(methodName, state).isEmpty();
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreJUnitMatchers.java

@@ -1,81 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import static com.google.common.collect.ImmutableSet.toImmutableSet;
-import static com.google.errorprone.matchers.ChildMultiMatcher.MatchType.AT_LEAST_ONE;
-import static com.google.errorprone.matchers.Matchers.annotations;
-import static com.google.errorprone.matchers.Matchers.anyOf;
-import static com.google.errorprone.matchers.Matchers.isType;
-import static java.util.Objects.requireNonNullElse;
-import static tech.picnic.errorprone.bugpatterns.util.MoreMatchers.hasMetaAnnotation;
-
-import com.google.common.base.Strings;
-import com.google.common.collect.ImmutableSet;
-import com.google.errorprone.matchers.AnnotationMatcherUtils;
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.matchers.MultiMatcher;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.AnnotationTree;
-import com.sun.source.tree.ExpressionTree;
-import com.sun.source.tree.MethodTree;
-import com.sun.source.tree.NewArrayTree;
-import org.jspecify.annotations.Nullable;
-
-/**
- * A collection of JUnit-specific helper methods and {@link Matcher}s.
- *
- * <p>These constants and methods are additions to the ones found in {@link
- * com.google.errorprone.matchers.JUnitMatchers}.
- */
-public final class MoreJUnitMatchers {
-  /** Matches JUnit Jupiter test methods. */
-  public static final MultiMatcher<MethodTree, AnnotationTree> TEST_METHOD =
-      annotations(
-          AT_LEAST_ONE,
-          anyOf(
-              isType("org.junit.jupiter.api.Test"),
-              hasMetaAnnotation("org.junit.jupiter.api.TestTemplate")));
-  /** Matches JUnit Jupiter setup and teardown methods. */
-  public static final MultiMatcher<MethodTree, AnnotationTree> SETUP_OR_TEARDOWN_METHOD =
-      annotations(
-          AT_LEAST_ONE,
-          anyOf(
-              isType("org.junit.jupiter.api.AfterAll"),
-              isType("org.junit.jupiter.api.AfterEach"),
-              isType("org.junit.jupiter.api.BeforeAll"),
-              isType("org.junit.jupiter.api.BeforeEach")));
-  /**
-   * Matches methods that have a {@link org.junit.jupiter.params.provider.MethodSource} annotation.
-   */
-  public static final MultiMatcher<MethodTree, AnnotationTree> HAS_METHOD_SOURCE =
-      annotations(AT_LEAST_ONE, isType("org.junit.jupiter.params.provider.MethodSource"));
-
-  private MoreJUnitMatchers() {}
-
-  /**
-   * Returns the names of the JUnit value factory methods specified by the given {@link
-   * org.junit.jupiter.params.provider.MethodSource} annotation.
-   *
-   * @param methodSourceAnnotation The annotation from which to extract value factory method names.
-   * @return One or more value factory names.
-   */
-  static ImmutableSet<String> getMethodSourceFactoryNames(
-      AnnotationTree methodSourceAnnotation, MethodTree method) {
-    String methodName = method.getName().toString();
-    ExpressionTree value = AnnotationMatcherUtils.getArgument(methodSourceAnnotation, "value");
-
-    if (!(value instanceof NewArrayTree)) {
-      return ImmutableSet.of(toMethodSourceFactoryName(value, methodName));
-    }
-
-    return ((NewArrayTree) value)
-        .getInitializers().stream()
-            .map(name -> toMethodSourceFactoryName(name, methodName))
-            .collect(toImmutableSet());
-  }
-
-  private static String toMethodSourceFactoryName(
-      @Nullable ExpressionTree tree, String annotatedMethodName) {
-    return requireNonNullElse(
-        Strings.emptyToNull(ASTHelpers.constValue(tree, String.class)), annotatedMethodName);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreMatchers.java

@@ -1,39 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import com.google.errorprone.matchers.Matcher;
-import com.google.errorprone.matchers.Matchers;
-import com.google.errorprone.predicates.TypePredicate;
-import com.google.errorprone.util.ASTHelpers;
-import com.sun.source.tree.AnnotationTree;
-import com.sun.tools.javac.code.Symbol;
-
-/**
- * A collection of general-purpose {@link Matcher}s.
- *
- * <p>These methods are additions to the ones found in {@link Matchers}.
- */
-public final class MoreMatchers {
-  private MoreMatchers() {}
-
-  /**
-   * Returns a {@link Matcher} that determines whether a given {@link AnnotationTree} has a
-   * meta-annotation of the specified type.
-   *
-   * @param <T> The type of tree to match against.
-   * @param annotationType The binary type name of the annotation (e.g.
-   *     "org.jspecify.annotations.Nullable", or "some.package.OuterClassName$InnerClassName")
-   * @return A {@link Matcher} that matches trees with the specified meta-annotation.
-   */
-  public static <T extends AnnotationTree> Matcher<T> hasMetaAnnotation(String annotationType) {
-    TypePredicate typePredicate = hasAnnotation(annotationType);
-    return (tree, state) -> {
-      Symbol sym = ASTHelpers.getSymbol(tree);
-      return sym != null && typePredicate.apply(sym.type, state);
-    };
-  }
-
-  // XXX: Consider moving to a `MoreTypePredicates` utility class.
-  private static TypePredicate hasAnnotation(String annotationClassName) {
-    return (type, state) -> ASTHelpers.hasAnnotation(type.tsym, annotationClassName, state);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/MoreTypes.java

@@ -1,132 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import static java.util.stream.Collectors.toCollection;
-
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.suppliers.Supplier;
-import com.google.errorprone.suppliers.Suppliers;
-import com.sun.tools.javac.code.BoundKind;
-import com.sun.tools.javac.code.Type;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.List;
-import java.util.Objects;
-import java.util.Optional;
-import java.util.function.BiFunction;
-
-/**
- * A set of helper methods which together define a DSL for defining {@link Type types}.
- *
- * <p>These methods are meant to be statically imported. Example usage:
- *
- * <pre>{@code
- * Supplier<Type> type =
- *     VisitorState.memoize(
- *         generic(
- *             type("reactor.core.publisher.Flux"),
- *             subOf(generic(type("org.reactivestreams.Publisher"), unbound()))));
- * }</pre>
- *
- * This statement produces a memoized supplier of the type {@code Flux<? extends Publisher<?>>}.
- */
-public final class MoreTypes {
-  private MoreTypes() {}
-
-  /**
-   * Creates a supplier of the type with the given fully qualified name.
-   *
-   * <p>This method should only be used when building more complex types in combination with other
-   * {@link MoreTypes} methods. In other cases prefer directly calling {@link
-   * Suppliers#typeFromString(String)}.
-   *
-   * @param typeName The type of interest.
-   * @return A supplier which returns the described type if available in the given state, and {@code
-   *     null} otherwise.
-   */
-  public static Supplier<Type> type(String typeName) {
-    return Suppliers.typeFromString(typeName);
-  }
-
-  /**
-   * Creates a supplier of the described generic type.
-   *
-   * @param type The base type of interest.
-   * @param typeArgs The desired type arguments.
-   * @return A supplier which returns the described type if available in the given state, and {@code
-   *     null} otherwise.
-   */
-  // XXX: The given `type` should be a generic type, so perhaps `withParams` would be a better
-  // method name. But the DSL wouldn't look as nice that way.
-  @SafeVarargs
-  @SuppressWarnings("varargs")
-  public static Supplier<Type> generic(Supplier<Type> type, Supplier<Type>... typeArgs) {
-    return propagateNull(
-        type,
-        (state, baseType) -> {
-          List<Type> params =
-              Arrays.stream(typeArgs).map(s -> s.get(state)).collect(toCollection(ArrayList::new));
-          if (params.stream().anyMatch(Objects::isNull)) {
-            return null;
-          }
-
-          return state.getType(baseType, /* isArray= */ false, params);
-        });
-  }
-
-  /**
-   * Creates a raw (erased, non-generic) variant of the given type.
-   *
-   * @param type The base type of interest.
-   * @return A supplier which returns the described type if available in the given state, and {@code
-   *     null} otherwise.
-   */
-  public static Supplier<Type> raw(Supplier<Type> type) {
-    return propagateNull(type, (state, baseType) -> baseType.tsym.erasure(state.getTypes()));
-  }
-
-  /**
-   * Creates a {@code ? super T} wildcard type, with {@code T} bound to the given type.
-   *
-   * @param type The base type of interest.
-   * @return A supplier which returns the described type if available in the given state, and {@code
-   *     null} otherwise.
-   */
-  public static Supplier<Type> superOf(Supplier<Type> type) {
-    return propagateNull(
-        type,
-        (state, baseType) ->
-            new Type.WildcardType(baseType, BoundKind.SUPER, state.getSymtab().boundClass));
-  }
-
-  /**
-   * Creates a {@code ? extends T} wildcard type, with {@code T} bound to the given type.
-   *
-   * @param type The base type of interest.
-   * @return A supplier which returns the described type if available in the given state, and {@code
-   *     null} otherwise.
-   */
-  public static Supplier<Type> subOf(Supplier<Type> type) {
-    return propagateNull(
-        type,
-        (state, baseType) ->
-            new Type.WildcardType(
-                type.get(state), BoundKind.EXTENDS, state.getSymtab().boundClass));
-  }
-
-  /**
-   * Creates an unbound wildcard type ({@code ?}).
-   *
-   * @return A supplier which returns the described type.
-   */
-  public static Supplier<Type> unbound() {
-    return state ->
-        new Type.WildcardType(
-            state.getSymtab().objectType, BoundKind.UNBOUND, state.getSymtab().boundClass);
-  }
-
-  private static Supplier<Type> propagateNull(
-      Supplier<Type> type, BiFunction<VisitorState, Type, Type> transformer) {
-    return state ->
-        Optional.ofNullable(type.get(state)).map(t -> transformer.apply(state, t)).orElse(null);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/SourceCode.java

@@ -1,21 +1,14 @@
 package tech.picnic.errorprone.bugpatterns.util;
 
-import static com.sun.tools.javac.util.Position.NOPOS;
-
-import com.google.common.base.CharMatcher;
 import com.google.errorprone.VisitorState;
-import com.google.errorprone.fixes.SuggestedFix;
 import com.sun.source.tree.Tree;
-import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
 
 /**
  * A collection of Error Prone utility methods for dealing with the source code representation of
  * AST nodes.
  */
+// XXX: Can we locate this code in a better place? Maybe contribute it upstream?
 public final class SourceCode {
-  /** The complement of {@link CharMatcher#whitespace()}. */
-  private static final CharMatcher NON_WHITESPACE_MATCHER = CharMatcher.whitespace().negate();
-
   private SourceCode() {}
 
   /**
@@ -31,32 +24,4 @@ public final class SourceCode {
     String src = state.getSourceForNode(tree);
     return src != null ? src : tree.toString();
   }
-
-  /**
-   * Creates a {@link SuggestedFix} for the deletion of the given {@link Tree}, including any
-   * whitespace that follows it.
-   *
-   * <p>Removing trailing whitespace may prevent the introduction of an empty line at the start of a
-   * code block; such empty lines are not removed when formatting the code using Google Java Format.
-   *
-   * @param tree The AST node of interest.
-   * @param state A {@link VisitorState} describing the context in which the given {@link Tree} is
-   *     found.
-   * @return A non-{@code null} {@link SuggestedFix} similar to one produced by {@link
-   *     SuggestedFix#delete(Tree)}.
-   */
-  public static SuggestedFix deleteWithTrailingWhitespace(Tree tree, VisitorState state) {
-    CharSequence sourceCode = state.getSourceCode();
-    int endPos = state.getEndPosition(tree);
-    if (sourceCode == null || endPos == NOPOS) {
-      /* We can't identify the trailing whitespace; delete just the tree. */
-      return SuggestedFix.delete(tree);
-    }
-
-    int whitespaceEndPos = NON_WHITESPACE_MATCHER.indexIn(sourceCode, endPos);
-    return SuggestedFix.replace(
-        ((DiagnosticPosition) tree).getStartPosition(),
-        whitespaceEndPos == -1 ? sourceCode.length() : whitespaceEndPos,
-        "");
-  }
 }

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/ThirdPartyLibrary.java

@@ -1,105 +0,0 @@
-package tech.picnic.errorprone.bugpatterns.util;
-
-import com.google.errorprone.VisitorState;
-import com.google.errorprone.bugpatterns.BugChecker;
-import com.google.errorprone.suppliers.Supplier;
-import com.sun.tools.javac.code.ClassFinder;
-import com.sun.tools.javac.code.Symbol.CompletionFailure;
-import com.sun.tools.javac.util.Name;
-
-/**
- * Utility class that helps decide whether it is appropriate to introduce references to (well-known)
- * third-party libraries.
- *
- * <p>This class should be used by {@link BugChecker}s that may otherwise suggest the introduction
- * of code that depends on possibly-not-present third-party libraries.
- */
-// XXX: Consider giving users more fine-grained control. This would be beneficial in cases where a
-// dependency is on the classpath, but new usages are undesirable.
-public enum ThirdPartyLibrary {
-  /**
-   * AssertJ.
-   *
-   * @see <a href="https://assertj.github.io/doc">AssertJ documentation</a>
-   */
-  ASSERTJ("org.assertj.core.api.Assertions"),
-  /**
-   * Google's Guava.
-   *
-   * @see <a href="https://github.com/google/guava">Guava on GitHub</a>
-   */
-  GUAVA("com.google.common.collect.ImmutableList"),
-  /**
-   * New Relic's Java agent API.
-   *
-   * @see <a href="https://github.com/newrelic/newrelic-java-agent/tree/main/newrelic-api">New Relic
-   *     Java agent API on GitHub</a>
-   */
-  NEW_RELIC_AGENT_API("com.newrelic.api.agent.Agent"),
-  /**
-   * VMWare's Project Reactor.
-   *
-   * @see <a href="https://projectreactor.io">Home page</a>
-   */
-  REACTOR("reactor.core.publisher.Flux");
-
-  private static final String IGNORE_CLASSPATH_COMPAT_FLAG =
-      "ErrorProneSupport:IgnoreClasspathCompat";
-
-  @SuppressWarnings("ImmutableEnumChecker" /* Supplier is deterministic. */)
-  private final Supplier<Boolean> canUse;
-
-  /**
-   * Instantiates a {@link ThirdPartyLibrary} enum value.
-   *
-   * @param witnessFqcn The fully-qualified class name of a type that is expected to be on the
-   *     classpath iff the associated third-party library is on the classpath.
-   */
-  ThirdPartyLibrary(String witnessFqcn) {
-    this.canUse = VisitorState.memoize(state -> canIntroduceUsage(witnessFqcn, state));
-  }
-
-  /**
-   * Tells whether it is okay to introduce a dependency on this well-known third party library in
-   * the given context.
-   *
-   * @param state The context under consideration.
-   * @return {@code true} iff it is okay to assume or create a dependency on this library.
-   */
-  public boolean isIntroductionAllowed(VisitorState state) {
-    return canUse.get(state);
-  }
-
-  private static boolean canIntroduceUsage(String className, VisitorState state) {
-    return shouldIgnoreClasspath(state) || isKnownClass(className, state);
-  }
-
-  /**
-   * Attempts to determine whether a class with the given FQCN is on the classpath.
-   *
-   * <p>The {@link VisitorState}'s symbol table is consulted first. If the type has not yet been
-   * loaded, then an attempt is made to do so.
-   */
-  private static boolean isKnownClass(String className, VisitorState state) {
-    return state.getTypeFromString(className) != null || canLoadClass(className, state);
-  }
-
-  private static boolean canLoadClass(String className, VisitorState state) {
-    ClassFinder classFinder = ClassFinder.instance(state.context);
-    Name binaryName = state.binaryNameFromClassname(className);
-    try {
-      classFinder.loadClass(state.getSymtab().unnamedModule, binaryName);
-      return true;
-    } catch (CompletionFailure e) {
-      return false;
-    }
-  }
-
-  private static boolean shouldIgnoreClasspath(VisitorState state) {
-    return state
-        .errorProneOptions()
-        .getFlags()
-        .getBoolean(IGNORE_CLASSPATH_COMPAT_FLAG)
-        .orElse(Boolean.FALSE);
-  }
-}

error-prone-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/util/package-info.java

@@ -1,4 +1,4 @@
 /** Auxiliary utilities for use by Error Prone checks. */
 @com.google.errorprone.annotations.CheckReturnValue
-@org.jspecify.annotations.NullMarked
+@javax.annotation.ParametersAreNonnullByDefault
 package tech.picnic.errorprone.bugpatterns.util;