Remove trailing comma if last two enum entries are on the same line a…

…nd trailing commas are not allowed Closes #1905
pinterest · Mar 31, 2023 · b3208ca · b3208ca
1 parent 75cfb75
commit b3208ca
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Showing 3 changed files with 33 additions and 11 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -275,6 +275,7 @@ Previously the default value for `.editorconfig` property `max_line_length` was
 * Wrap each type parameter in a multiline type parameter list `wrapping` ([#1867](https://github.com/pinterest/ktlint/issues/1867))
 * Allow value arguments with a multiline expression to be indented on a separate line `indent` ([#1217](https://github.com/pinterest/ktlint/issues/1217))
 * When enabled, the ktlint rule checking is disabled for all code surrounded by the formatter tags (see [faq](https://pinterest.github.io/ktlint/faq/#are-formatter-tags-respected)) ([#670](https://github.com/pinterest/ktlint/issues/670)) 
+* Remove trailing comma if last two enum entries are on the same line and trailing commas are not allowed. `trailing-comma-on-declaration-site` ([#1905](https://github.com/pinterest/ktlint/issues/1905))
 
 ### Changed
 * Wrap the parameters of a function literal containing a multiline parameter list (only in `ktlint_official` code style) `parameter-list-wrapping` ([#1681](https://github.com/pinterest/ktlint/issues/1681)).

diff --git a/.../kotlin/com/pinterest/ktlint/ruleset/standard/rules/TrailingCommaOnDeclarationSiteRule.kt b/.../kotlin/com/pinterest/ktlint/ruleset/standard/rules/TrailingCommaOnDeclarationSiteRule.kt
@@ -6,6 +6,7 @@ import com.pinterest.ktlint.rule.engine.core.api.ElementType.CLASS
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.DESTRUCTURING_DECLARATION
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.FUNCTION_LITERAL
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.FUNCTION_TYPE
+import com.pinterest.ktlint.rule.engine.core.api.ElementType.RBRACE
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.TYPE_PARAMETER_LIST
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.VALUE_PARAMETER_LIST
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.WHEN_ENTRY
@@ -184,6 +185,7 @@ public class TrailingCommaOnDeclarationSiteRule :
             emit = emit,
         )
     }
+
     private fun visitClass(
         node: ASTNode,
         emit: (offset: Int, errorMessage: String, canBeAutoCorrected: Boolean) -> Unit,
@@ -195,18 +197,30 @@ public class TrailingCommaOnDeclarationSiteRule :
         node
             .takeIf { psi.isEnum() }
             ?.findChildByType(ElementType.CLASS_BODY)
-            ?.takeUnless {
-                it.noEnumEntries() || it.lastTwoEnumEntriesAreOnSameLine()
-            }?.let { classBody ->
+            ?.takeUnless { it.noEnumEntries() }
+            ?.let { classBody ->
                 classBody
                     .findNodeAfterLastEnumEntry()
                     ?.let { nodeAfterLastEnumEntry ->
-                        node.reportAndCorrectTrailingCommaNodeBefore(
-                            inspectNode = nodeAfterLastEnumEntry,
-                            isTrailingCommaAllowed = node.isTrailingCommaAllowed(),
-                            autoCorrect = autoCorrect,
-                            emit = emit,
-                        )
+                        when {
+                            !node.isTrailingCommaAllowed() && nodeAfterLastEnumEntry.elementType == RBRACE -> {
+                                node.reportAndCorrectTrailingCommaNodeBefore(
+                                    inspectNode = nodeAfterLastEnumEntry,
+                                    isTrailingCommaAllowed = false,
+                                    autoCorrect = autoCorrect,
+                                    emit = emit,
+                                )
+                            }
+
+                            !classBody.lastTwoEnumEntriesAreOnSameLine() -> {
+                                node.reportAndCorrectTrailingCommaNodeBefore(
+                                    inspectNode = nodeAfterLastEnumEntry,
+                                    isTrailingCommaAllowed = node.isTrailingCommaAllowed(),
+                                    autoCorrect = autoCorrect,
+                                    emit = emit,
+                                )
+                            }
+                        }
                     }
             }
     }

diff --git a/...lin/com/pinterest/ktlint/ruleset/standard/rules/TrailingCommaOnDeclarationSiteRuleTest.kt b/...lin/com/pinterest/ktlint/ruleset/standard/rules/TrailingCommaOnDeclarationSiteRuleTest.kt
@@ -708,16 +708,23 @@ class TrailingCommaOnDeclarationSiteRuleTest {
     }
 
     @Test
-    fun `Given that a trailing comma is not allowed then it is not removed for enums where last two entries are on same line`() {
+    fun `Given that a trailing comma is not allowed then remove it for enums where last two entries are on same line and followed by trailing comma`() {
         val code =
             """
             enum class Shape {
                 SQUARE, TRIANGLE,
             }
             """.trimIndent()
+        val formattedCode =
+            """
+            enum class Shape {
+                SQUARE, TRIANGLE
+            }
+            """.trimIndent()
         trailingCommaOnDeclarationSiteRuleAssertThat(code)
             .withEditorConfigOverride(TRAILING_COMMA_ON_DECLARATION_SITE_PROPERTY to false)
-            .hasNoLintViolations()
+            .hasLintViolation(2, 21, "Unnecessary trailing comma before \"}\"")
+            .isFormattedAs(formattedCode)
     }
 
     @Nested