From 3b25af66921a24d12df2c65ae57dabd211bd37a5 Mon Sep 17 00:00:00 2001
From: Paul Dingemans <paul-dingemans@users.noreply.github.com>
Date: Sat, 3 Feb 2024 16:13:42 +0100
Subject: [PATCH] Fix false positive newline expected before comment in enum
 (#2527)

Closes #2510
---
 .../standard/rules/EnumWrappingRule.kt        | 11 +++++---
 .../standard/rules/EnumWrappingRuleTest.kt    | 28 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRule.kt b/ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRule.kt
index 6bbf36e2c9..8b197d48ec 100644
--- a/ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRule.kt
+++ b/ktlint-ruleset-standard/src/main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRule.kt
@@ -15,9 +15,11 @@ import com.pinterest.ktlint.rule.engine.core.api.children
 import com.pinterest.ktlint.rule.engine.core.api.editorconfig.EditorConfig
 import com.pinterest.ktlint.rule.engine.core.api.editorconfig.INDENT_SIZE_PROPERTY
 import com.pinterest.ktlint.rule.engine.core.api.editorconfig.INDENT_STYLE_PROPERTY
+import com.pinterest.ktlint.rule.engine.core.api.firstChildLeafOrSelf
 import com.pinterest.ktlint.rule.engine.core.api.isPartOfComment
 import com.pinterest.ktlint.rule.engine.core.api.isWhiteSpaceWithNewline
 import com.pinterest.ktlint.rule.engine.core.api.isWhiteSpaceWithoutNewline
+import com.pinterest.ktlint.rule.engine.core.api.leavesIncludingSelf
 import com.pinterest.ktlint.rule.engine.core.api.nextCodeSibling
 import com.pinterest.ktlint.rule.engine.core.api.nextSibling
 import com.pinterest.ktlint.rule.engine.core.api.prevLeaf
@@ -85,16 +87,17 @@ public class EnumWrappingRule :
         emit: (offset: Int, errorMessage: String, canBeAutoCorrected: Boolean) -> Unit,
         autoCorrect: Boolean,
     ): Boolean {
-        val firstEnumEntry = node.findChildByType(ENUM_ENTRY)
+        val firstEnumEntry = node.findChildByType(ENUM_ENTRY)?.firstChildLeafOrSelf()
         if (firstEnumEntry != null) {
             node
-                .children()
+                .firstChildLeafOrSelf()
+                .leavesIncludingSelf()
                 .takeWhile { it != firstEnumEntry }
                 .firstOrNull { it.isPartOfComment() }
                 ?.let { commentBeforeFirstEnumEntry ->
-                    val expectedIndent = indentConfig.parentIndentOf(node)
+                    val expectedIndent = indentConfig.childIndentOf(node)
                     if (commentBeforeFirstEnumEntry.prevLeaf()?.text != expectedIndent) {
-                        emit(node.startOffset, "Expected a newline before comment", true)
+                        emit(node.startOffset, "Expected a (single) newline before comment", true)
                         if (autoCorrect) {
                             commentBeforeFirstEnumEntry.upsertWhitespaceBeforeMe(indentConfig.siblingIndentOf(node))
                         }
diff --git a/ktlint-ruleset-standard/src/test/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRuleTest.kt b/ktlint-ruleset-standard/src/test/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRuleTest.kt
index 314ff057a4..771d39a903 100644
--- a/ktlint-ruleset-standard/src/test/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRuleTest.kt
+++ b/ktlint-ruleset-standard/src/test/kotlin/com/pinterest/ktlint/ruleset/standard/rules/EnumWrappingRuleTest.kt
@@ -153,7 +153,7 @@ class EnumWrappingRuleTest {
                 """.trimIndent()
             enumWrappingRuleAssertThat(code)
                 .hasLintViolations(
-                    LintViolation(1, 16, "Expected a newline before comment"),
+                    LintViolation(1, 16, "Expected a (single) newline before comment"),
                     LintViolation(1, 32, "Enum entry should start on a separate line"),
                     LintViolation(1, 35, "Enum entry should start on a separate line"),
                     LintViolation(1, 37, "Expected newline before '}'"),
@@ -242,4 +242,30 @@ class EnumWrappingRuleTest {
             """.trimIndent()
         enumWrappingRuleAssertThat(code).hasNoLintViolations()
     }
+
+    @Test
+    fun `Issue 2510 - Given an enum class with comment before the first entry`() {
+        val code =
+            """
+            enum class FooBar {
+
+                // Some comment about FooBar
+
+                // Foo
+                Foo,
+            }
+            """.trimIndent()
+        val formattedCode =
+            """
+            enum class FooBar {
+                // Some comment about FooBar
+
+                // Foo
+                Foo,
+            }
+            """.trimIndent()
+        enumWrappingRuleAssertThat(code)
+            .hasLintViolation(1, 19, "Expected a (single) newline before comment")
+            .isFormattedAs(formattedCode)
+    }
 }