Add support for manageTrailingCommas (cortinico#272)

Fixes cortinico#260

CHANGELOG.md

@@ -7,6 +7,7 @@ Please add your entries according to this format.
 ## Unreleased
 
 - Make `KtfmtCheckTask` cacheable
+- Add support for `manageTrailingCommas` and enables it by default for googleStyle
 
 ## Version 0.17.0 *(2024-01-31)*
 

README.md

@@ -92,7 +92,7 @@ ktfmt {
     // Dropbox style - 4 space indentation
     dropboxStyle()
 
-    // Google style - 2 space indentation
+    // Google style - 2 space indentation & automatically adds/removes trailing commas
     googleStyle()
 
     // KotlinLang style - 4 space indentation - From kotlinlang.org/docs/coding-conventions.html
@@ -112,6 +112,8 @@ ktfmt {
     continuationIndent.set(8)
     // Whether ktfmt should remove imports that are not used.
     removeUnusedImports.set(false)
+    // Whether ktfmt should automatically add/remove trailing commas.
+    manageTrailingCommas.set(false)
 }
 ```
 
@@ -144,4 +146,4 @@ Feel free to open a issue or submit a pull request for any bugs/improvements.
 
 ## License 📄
 
-This project is licensed under the MIT License - see the [License](License) file for details
+This project is licensed under the MIT License - see the [License](License) file for details

plugin-build/plugin/api/plugin.api

@@ -4,6 +4,7 @@ public abstract class com/ncorti/ktfmt/gradle/KtfmtExtension {
 	public abstract fun getBlockIndent ()Lorg/gradle/api/provider/Property;
 	public abstract fun getContinuationIndent ()Lorg/gradle/api/provider/Property;
 	public abstract fun getDebuggingPrintOpsAfterFormatting ()Lorg/gradle/api/provider/Property;
+	public abstract fun getManageTrailingCommas ()Lorg/gradle/api/provider/Property;
 	public abstract fun getMaxWidth ()Lorg/gradle/api/provider/Property;
 	public abstract fun getRemoveUnusedImports ()Lorg/gradle/api/provider/Property;
 	public final fun googleStyle ()V

plugin-build/plugin/src/main/java/com/ncorti/ktfmt/gradle/FormattingOptionsBean.kt

@@ -34,14 +34,23 @@ internal data class FormattingOptionsBean(
      */
     val continuationIndent: Int = 4,
 
+    /**
+     * Automatically remove and insert trialing commas.
+     *
+     * Lists that cannot fit on one line will have trailing commas inserted. Lists that span
+     * multiple lines will have them removed. Manually inserted trailing commas cannot be used as a
+     * hint to force breaking lists to multiple lines.
+     */
+    val manageTrailingCommas: Boolean = false,
+
     /** Whether ktfmt should remove imports that are not used. */
     val removeUnusedImports: Boolean = true,
 
     /**
      * Print the Ops generated by KotlinInputAstVisitor to help reason about formatting (i.e.,
      * newline) decisions
      */
-    val debuggingPrintOpsAfterFormatting: Boolean = false
+    val debuggingPrintOpsAfterFormatting: Boolean = false,
 ) : Serializable {
     enum class Style {
         FACEBOOK,

plugin-build/plugin/src/main/java/com/ncorti/ktfmt/gradle/KtfmtExtension.kt

@@ -14,6 +14,7 @@ abstract class KtfmtExtension {
         continuationIndent.convention(DEFAULT_CONTINUATION_INDENT)
         removeUnusedImports.convention(DEFAULT_REMOVE_UNUSED_IMPORTS)
         debuggingPrintOpsAfterFormatting.convention(DEFAULT_DEBUGGING_PRINT_OPTS)
+        manageTrailingCommas.convention(DEFAULT_MANAGE_TRAILING_COMMAS)
     }
 
     internal var ktfmtStyle = FACEBOOK
@@ -45,6 +46,15 @@ abstract class KtfmtExtension {
      */
     abstract val continuationIndent: Property<Int>
 
+    /**
+     * Automatically remove and insert trialing commas.
+     *
+     * Lists that cannot fit on one line will have trailing commas inserted. Lists that span
+     * multiple lines will have them removed. Manually inserted trailing commas cannot be used as a
+     * hint to force breaking lists to multiple lines.
+     */
+    abstract val manageTrailingCommas: Property<Boolean>
+
     /** Whether ktfmt should remove imports that are not used. */
     abstract val removeUnusedImports: Property<Boolean>
 
@@ -68,6 +78,7 @@ abstract class KtfmtExtension {
         ktfmtStyle = GOOGLE
         blockIndent.set(2)
         continuationIndent.set(2)
+        manageTrailingCommas.set(true)
     }
 
     /**
@@ -88,6 +99,7 @@ abstract class KtfmtExtension {
             blockIndent = blockIndent.get(),
             continuationIndent = continuationIndent.get(),
             removeUnusedImports = removeUnusedImports.get(),
+            manageTrailingCommas = manageTrailingCommas.get(),
             debuggingPrintOpsAfterFormatting = debuggingPrintOpsAfterFormatting.get()
         )
 
@@ -97,5 +109,6 @@ abstract class KtfmtExtension {
         internal const val DEFAULT_CONTINUATION_INDENT: Int = 4
         internal const val DEFAULT_REMOVE_UNUSED_IMPORTS: Boolean = true
         internal const val DEFAULT_DEBUGGING_PRINT_OPTS: Boolean = false
+        internal const val DEFAULT_MANAGE_TRAILING_COMMAS: Boolean = false
     }
 }

plugin-build/plugin/src/main/java/com/ncorti/ktfmt/gradle/tasks/worker/KtfmtFormatter.kt

@@ -60,6 +60,7 @@ internal fun FormattingOptionsBean.toFormattingOptions(): FormattingOptions =
         blockIndent = blockIndent,
         continuationIndent = continuationIndent,
         removeUnusedImports = removeUnusedImports,
+        manageTrailingCommas = manageTrailingCommas,
         debuggingPrintOpsAfterFormatting = debuggingPrintOpsAfterFormatting
     )
 

plugin-build/plugin/src/test/java/com/ncorti/ktfmt/gradle/FormattingOptionsBeanTest.kt

@@ -14,6 +14,7 @@ class FormattingOptionsBeanTest {
                 blockIndent = 43,
                 continuationIndent = 44,
                 removeUnusedImports = false,
+                manageTrailingCommas = true,
                 debuggingPrintOpsAfterFormatting = true
             )
 
@@ -23,6 +24,7 @@ class FormattingOptionsBeanTest {
         assertThat(opts.blockIndent).isEqualTo(43)
         assertThat(opts.continuationIndent).isEqualTo(44)
         assertThat(opts.removeUnusedImports).isEqualTo(false)
+        assertThat(opts.manageTrailingCommas).isEqualTo(true)
         assertThat(opts.debuggingPrintOpsAfterFormatting).isEqualTo(true)
     }
 }

plugin-build/plugin/src/test/java/com/ncorti/ktfmt/gradle/KtfmtExtensionTest.kt

@@ -90,6 +90,7 @@ class KtfmtExtensionTest {
         extension.blockIndent.set(43)
         extension.continuationIndent.set(44)
         extension.removeUnusedImports.set(false)
+        extension.manageTrailingCommas.set(true)
         extension.debuggingPrintOpsAfterFormatting.set(true)
 
         val bean = extension.toBean()
@@ -98,6 +99,7 @@ class KtfmtExtensionTest {
         assertThat(bean.blockIndent).isEqualTo(43)
         assertThat(bean.continuationIndent).isEqualTo(44)
         assertThat(bean.removeUnusedImports).isEqualTo(false)
+        assertThat(bean.manageTrailingCommas).isEqualTo(true)
         assertThat(bean.debuggingPrintOpsAfterFormatting).isEqualTo(true)
     }