Add tests showing how to exclude custom config properties in plugins (#2192)

* Add tests showing how to exclude custom plugin properties in configuration files - #2169

* Mention config validation excludes in the website under extensions

detekt-cli/src/main/kotlin/io/gitlab/arturbosch/detekt/cli/CliArgs.kt

@@ -16,7 +16,7 @@ class CliArgs : Args {
         description = "Input paths to analyze. Multiple paths are separated by comma. If not specified the " +
             "current working directory is used."
     )
-    private var input: String? = null
+    var input: String? = null
 
     @Parameter(
         names = ["--includes", "-in"],

detekt-sample-extensions/build.gradle.kts

@@ -3,13 +3,15 @@ val junitPlatformVersion: String by project
 val spekVersion: String by project
 
 dependencies {
-    // When creating a sample extension, change this dependency to the detekt-api version you build against, e.g.
-    // io.gitlab.arturbosch.detekt:detekt-api:1.0.0-RC15
+    // When creating a sample extension, change this dependency to the detekt-api version you build against
+    // e.g. io.gitlab.arturbosch.detekt:detekt-api:1.x.x
     implementation(project(":detekt-api"))
-
-    // When creating a sample extension, change this dependency to the detekt-test version you build against, e.g.
-    // io.gitlab.arturbosch.detekt:detekt-test:1.0.0-RC15
+    // When creating a sample extension, change this dependency to the detekt-test version you build against
+    // e.g. io.gitlab.arturbosch.detekt:detekt-test:1.x.x
     testImplementation(project(":detekt-test"))
+    // Do you want to write integration or system tests? Add the cli dependency.
+    testImplementation(project(":detekt-cli"))
+
     testImplementation("org.assertj:assertj-core:$assertjVersion")
     testImplementation("org.spekframework.spek2:spek-dsl-jvm:$spekVersion")
 

detekt-sample-extensions/src/test/kotlin/io/gitlab/arturbosch/detekt/sample/extensions/SupportConfigValidationSpec.kt

@@ -0,0 +1,38 @@
+package io.gitlab.arturbosch.detekt.sample.extensions
+
+import io.gitlab.arturbosch.detekt.cli.CliArgs
+import io.gitlab.arturbosch.detekt.cli.InvalidConfig
+import io.gitlab.arturbosch.detekt.cli.runners.Runner
+import org.assertj.core.api.Assertions.assertThatCode
+import org.spekframework.spek2.Spek
+import org.spekframework.spek2.style.specification.describe
+import java.nio.file.Files
+
+class SupportConfigValidationSpec : Spek({
+
+    describe("support config validation") {
+
+        val testDir = Files.createTempDirectory("detekt-sample")
+
+        it("fails when new rule set is not excluded") {
+            val args = CliArgs {
+                input = testDir.toString()
+                configResource = "included-config.yml"
+            }
+
+            assertThatCode { Runner(args).execute() }
+                .isInstanceOf(InvalidConfig::class.java)
+                .hasMessage("Run failed with 1 invalid config property.")
+        }
+
+        it("passes with excluded new rule set") {
+            val args = CliArgs {
+                input = testDir.toString()
+                configResource = "excluded-config.yml"
+            }
+
+            assertThatCode { Runner(args).execute() }
+                .doesNotThrowAnyException()
+        }
+    }
+})

detekt-sample-extensions/src/test/resources/excluded-config.yml

@@ -0,0 +1,9 @@
+config:
+  validation: true
+  # 1. exclude rule set 'sample' and all its nested members
+  # 2. exclude every property in every rule under the rule set 'sample'
+  excludes: "sample.*,sample>.*>.*"
+
+sample:
+  TooManyFunctions:
+    active: true

detekt-sample-extensions/src/test/resources/included-config.yml

@@ -0,0 +1,3 @@
+sample:
+  TooManyFunctions:
+    active: true

docs/pages/extensions.md

@@ -97,6 +97,17 @@ By specifying the rule set and rule ids, _detekt_ will use the sub configuration
 
 ```val threshold = valueOrDefault("threshold", THRESHOLD)```
 
+Note: As of version 1.2.0 detekt now verifies if all configured properties actually exist in a configuration created by `--generate-config`.
+This means that by default detekt does not know about your new properties.
+Therefore we need to mention them in the configuration under `config>excludes`:
+
+```yaml
+config:
+  validation: true
+  # 1. exclude rule set 'sample' and all its nested members
+  # 2. exclude every property in every rule under the rule set 'sample'
+  excludes: "sample.*,sample>.*>.*"
+```
 
 ##### <a name="testing">Testing your rules</a>