Update Checkstyle integration test (#1424)

Summary of changes:
- Move Checkstyle-specific build parameters out of
  `run-integration-test.sh`.
- Build with `-Dmaven.compiler.failOnError=true` to compensate for
  `<failOnError>false</failOnError>` configured by the enabled Maven
  profiles.
- Tweak `XdocGenerator.java` logic prior to integration test execution,
  to work around a subtle semantic difference introduced by the
  `FilesCreateTempFileToFile` Refaster rule.
- Document this difference on the relevant Refaster rules.
- To aid debugging, run Maven commands with `set -x`, such that the
  exact command executed is logged.
- Update the patch file containing the expected changes.

error-prone-contrib/src/main/java/tech/picnic/errorprone/refasterrules/FileRules.java

@@ -93,6 +93,12 @@ final class FileRules {
   /**
    * Prefer {@link Files#createTempFile(String, String, FileAttribute[])} over alternatives that
    * create files with more liberal permissions.
+   *
+   * <p>Note that {@link File#createTempFile} treats the given prefix as a path, and ignores all but
+   * its file name. That is, the actual prefix used is derived from all characters following the
+   * final file separator (if any). This is not the case with {@link Files#createTempFile}, which
+   * will instead throw an {@link IllegalArgumentException} if the prefix contains any file
+   * separators.
    */
   static final class FilesCreateTempFileToFile {
     @BeforeTemplate
@@ -117,6 +123,12 @@ final class FileRules {
   /**
    * Prefer {@link Files#createTempFile(Path, String, String, FileAttribute[])} over alternatives
    * that create files with more liberal permissions.
+   *
+   * <p>Note that {@link File#createTempFile} treats the given prefix as a path, and ignores all but
+   * its file name. That is, the actual prefix used is derived from all characters following the
+   * final file separator (if any). This is not the case with {@link Files#createTempFile}, which
+   * will instead throw an {@link IllegalArgumentException} if the prefix contains any file
+   * separators.
    */
   static final class FilesCreateTempFileInCustomDirectoryToFile {
     @BeforeTemplate

integration-tests/checkstyle-init.patch

@@ -134,6 +134,26 @@
  public class TreeWalkerTest extends AbstractModuleTestSupport {
  
      @TempDir
+--- a/src/test/java/com/puppycrawl/tools/checkstyle/internal/utils/XdocGenerator.java
++++ b/src/test/java/com/puppycrawl/tools/checkstyle/internal/utils/XdocGenerator.java
+@@ -55,7 +55,8 @@ public final class XdocGenerator {
+         for (Path path : templatesFilePaths) {
+             final String pathToFile = path.toString();
+             final File inputFile = new File(pathToFile);
+-            final File tempFile = File.createTempFile(pathToFile.replace(".template", ""), "");
++            final File outputFile = new File(pathToFile.replace(".template", ""));
++            final File tempFile = File.createTempFile(outputFile.getName(), "");
+             tempFile.deleteOnExit();
+             final XdocsTemplateSinkFactory sinkFactory = (XdocsTemplateSinkFactory)
+                     plexus.lookup(SinkFactory.ROLE, XDOCS_TEMPLATE_HINT);
+@@ -70,7 +71,6 @@ public final class XdocGenerator {
+             finally {
+                 sink.close();
+             }
+-            final File outputFile = new File(pathToFile.replace(".template", ""));
+             final StandardCopyOption copyOption = StandardCopyOption.REPLACE_EXISTING;
+             Files.copy(tempFile.toPath(), outputFile.toPath(), copyOption);
+         }
 --- a/src/test/java/com/puppycrawl/tools/checkstyle/utils/CheckUtilTest.java
 +++ b/src/test/java/com/puppycrawl/tools/checkstyle/utils/CheckUtilTest.java
 @@ -47,6 +47,8 @@ import com.puppycrawl.tools.checkstyle.checks.coding.NestedIfDepthCheck;

integration-tests/checkstyle.sh

@@ -7,7 +7,7 @@ project='checkstyle'
 repository='https://github.com/checkstyle/checkstyle.git'
 revision='checkstyle-10.14.0'
 # XXX: Configure Renovate to manage the AssertJ version declared here.
-additional_build_flags='-Dassertj.version=3.24.2'
+additional_build_flags='-Perror-prone-compile,error-prone-test-compile -Dassertj.version=3.24.2 -Dmaven.compiler.failOnError=true'
 additional_source_directories='${project.basedir}${file.separator}src${file.separator}it${file.separator}java,${project.basedir}${file.separator}src${file.separator}xdocs-examples${file.separator}java'
 patch_error_prone_flags=''
 validation_error_prone_flags=''

integration-tests/run-integration-test.sh

@@ -52,7 +52,6 @@ case "$(uname -s)" in
 esac
 
 shared_build_flags="
-  -Perror-prone-compile,error-prone-test-compile
   -Derror-prone.version=$(
     mvn -f "${error_prone_support_root}" help:evaluate -Dexpression=version.error-prone -q -DforceStdout
   )
@@ -141,10 +140,13 @@ diff_base="$(git rev-parse HEAD)"
 function apply_patch() {
   local extra_build_args="${1}"
 
-  mvn ${shared_build_flags} ${extra_build_args} \
-    package "${format_goal}" \
-    -Derror-prone.configuration-args="${error_prone_patch_flags}" \
-    -DskipTests
+  (
+    set -x \
+      && mvn ${shared_build_flags} ${extra_build_args} \
+           package "${format_goal}" \
+           -Derror-prone.configuration-args="${error_prone_patch_flags}" \
+           -DskipTests
+  )
 
   if ! git diff --exit-code; then
     git commit -m 'minor: Apply patches' .
@@ -168,12 +170,13 @@ apply_patch ''
 # By also running the tests, we validate that the (majority of) applied changes
 # are behavior preserving.
 validation_build_log="${report_directory}/${test_name}-validation-build-log.txt"
-mvn ${shared_build_flags} \
-      clean package \
-      -Derror-prone.configuration-args="${error_prone_validation_flags}" \
-      ${validation_build_flags} \
-    | tee "${validation_build_log}" \
-  || failure=1
+(
+  set -x \
+    && mvn ${shared_build_flags} \
+         clean package \
+         -Derror-prone.configuration-args="${error_prone_validation_flags}" \
+         ${validation_build_flags}
+) | tee "${validation_build_log}" || failure=1
 
 # Collect the applied changes.
 expected_changes="${integration_test_root}/${test_name}-expected-changes.patch"