Update documentation for TrailingComma rules (#5513)

* Update default config of TrailingComma to upstream

* Update detekt-formatting/src/main/kotlin/io/gitlab/arturbosch/detekt/formatting/wrappers/TrailingCommaOnDeclarationSite.kt

Co-authored-by: Matthew Haughton <3flex@users.noreply.github.com>

* Update detekt-formatting/src/main/kotlin/io/gitlab/arturbosch/detekt/formatting/wrappers/TrailingCommaOnCallSite.kt

Co-authored-by: Matthew Haughton <3flex@users.noreply.github.com>

* Update doc to reflect ktlint to be an upstream

* Update .gitignore

Co-authored-by: Matthew Haughton <3flex@users.noreply.github.com>

detekt-formatting/src/main/kotlin/io/gitlab/arturbosch/detekt/formatting/wrappers/TrailingCommaOnCallSite.kt

@@ -3,22 +3,32 @@ package io.gitlab.arturbosch.detekt.formatting.wrappers
 import com.pinterest.ktlint.core.api.UsesEditorConfigProperties
 import com.pinterest.ktlint.ruleset.standard.TrailingCommaOnCallSiteRule
 import io.gitlab.arturbosch.detekt.api.Config
-import io.gitlab.arturbosch.detekt.api.config
+import io.gitlab.arturbosch.detekt.api.configWithAndroidVariants
 import io.gitlab.arturbosch.detekt.api.internal.AutoCorrectable
 import io.gitlab.arturbosch.detekt.api.internal.Configuration
 import io.gitlab.arturbosch.detekt.formatting.FormattingRule
 
 /**
  * See [ktlint docs](https://pinterest.github.io/ktlint/rules/standard/) for documentation.
+ *
+ * The default config comes from ktlint and follows these conventions:
+ * - [Kotlin coding convention](https://kotlinlang.org/docs/coding-conventions.html#trailing-commas) recommends
+ * trailing comma encourage the use of trailing commas at the declaration site and
+ * leaves it at your discretion for the call site.
+ * - [Android Kotlin style guide](https://developer.android.com/kotlin/style-guide) does not include
+ * trailing comma usage yet.
  */
 @AutoCorrectable(since = "1.22.0")
 class TrailingCommaOnCallSite(config: Config) : FormattingRule(config) {
 
     override val wrapping = TrailingCommaOnCallSiteRule()
     override val issue = issueFor("Rule to mandate/forbid trailing commas at call sites")
 
-    @Configuration("Defines whether a trailing comma (or no trailing comma) should be enforced at call sites")
-    private val useTrailingCommaOnCallSite by config(false)
+    @Configuration("Defines whether trailing commas are required (true) or forbidden (false) at call sites")
+    private val useTrailingCommaOnCallSite by configWithAndroidVariants(
+        defaultValue = true,
+        defaultAndroidValue = false,
+    )
 
     override fun overrideEditorConfigProperties(): Map<UsesEditorConfigProperties.EditorConfigProperty<*>, String> =
         mapOf(

detekt-formatting/src/main/kotlin/io/gitlab/arturbosch/detekt/formatting/wrappers/TrailingCommaOnDeclarationSite.kt

@@ -3,22 +3,32 @@ package io.gitlab.arturbosch.detekt.formatting.wrappers
 import com.pinterest.ktlint.core.api.UsesEditorConfigProperties
 import com.pinterest.ktlint.ruleset.standard.TrailingCommaOnDeclarationSiteRule
 import io.gitlab.arturbosch.detekt.api.Config
-import io.gitlab.arturbosch.detekt.api.config
+import io.gitlab.arturbosch.detekt.api.configWithAndroidVariants
 import io.gitlab.arturbosch.detekt.api.internal.AutoCorrectable
 import io.gitlab.arturbosch.detekt.api.internal.Configuration
 import io.gitlab.arturbosch.detekt.formatting.FormattingRule
 
 /**
  * See [ktlint docs](https://pinterest.github.io/ktlint/rules/standard/) for documentation.
+ *
+ * The default config comes from ktlint and follows these conventions:
+ * - [Kotlin coding convention](https://kotlinlang.org/docs/coding-conventions.html#trailing-commas) recommends
+ * trailing comma encourage the use of trailing commas at the declaration site and
+ * leaves it at your discretion for the call site.
+ * - [Android Kotlin style guide](https://developer.android.com/kotlin/style-guide) does not include
+ * trailing comma usage yet.
  */
 @AutoCorrectable(since = "1.22.0")
 class TrailingCommaOnDeclarationSite(config: Config) : FormattingRule(config) {
 
     override val wrapping = TrailingCommaOnDeclarationSiteRule()
     override val issue = issueFor("Rule to mandate/forbid trailing commas at declaration sites")
 
-    @Configuration("Defines whether a trailing comma (or no trailing comma) should be enforced at declaration sites")
-    private val useTrailingCommaOnDeclarationSite by config(false)
+    @Configuration("Defines whether trailing commas are required (true) or forbidden (false) at declaration sites")
+    private val useTrailingCommaOnDeclarationSite by configWithAndroidVariants(
+        defaultValue = true,
+        defaultAndroidValue = false,
+    )
 
     override fun overrideEditorConfigProperties(): Map<UsesEditorConfigProperties.EditorConfigProperty<*>, String> =
         mapOf(

detekt-formatting/src/main/resources/config/config.yml

@@ -182,11 +182,11 @@ formatting:
   TrailingCommaOnCallSite:
     active: false
     autoCorrect: true
-    useTrailingCommaOnCallSite: false
+    useTrailingCommaOnCallSite: true
   TrailingCommaOnDeclarationSite:
     active: false
     autoCorrect: true
-    useTrailingCommaOnDeclarationSite: false
+    useTrailingCommaOnDeclarationSite: true
   TypeArgumentListSpacing:
     active: false
     autoCorrect: true