Fix false positive when anonymous function is used as value argument (#…

…2718) Closes #2694
pinterest · Jun 25, 2024 · 2ecb753 · 2ecb753
1 parent 9d9ad58
commit 2ecb753
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diff --git a/...main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/BlankLineBeforeDeclarationRule.kt b/...main/kotlin/com/pinterest/ktlint/ruleset/standard/rules/BlankLineBeforeDeclarationRule.kt
@@ -14,6 +14,7 @@ import com.pinterest.ktlint.rule.engine.core.api.ElementType.OBJECT_LITERAL
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.PROPERTY
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.PROPERTY_ACCESSOR
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.RETURN_KEYWORD
+import com.pinterest.ktlint.rule.engine.core.api.ElementType.VALUE_ARGUMENT
 import com.pinterest.ktlint.rule.engine.core.api.ElementType.WHEN
 import com.pinterest.ktlint.rule.engine.core.api.Rule
 import com.pinterest.ktlint.rule.engine.core.api.RuleId
@@ -132,6 +133,12 @@ public class BlankLineBeforeDeclarationRule :
             return
         }
 
+        if (node.elementType == FUN && node.treeParent.elementType == VALUE_ARGUMENT) {
+            // Allow:
+            //   val foo1 = foo2(fun() = 42)
+            return
+        }
+
         if (node.elementType == OBJECT_DECLARATION && node.treeParent.elementType == OBJECT_LITERAL) {
             // Allow:
             //   fun foo() =

diff --git a/.../kotlin/com/pinterest/ktlint/ruleset/standard/rules/BlankLineBeforeDeclarationRuleTest.kt b/.../kotlin/com/pinterest/ktlint/ruleset/standard/rules/BlankLineBeforeDeclarationRuleTest.kt
@@ -506,4 +506,18 @@ class BlankLineBeforeDeclarationRuleTest {
             """.trimIndent()
         blankLineBeforeDeclarationRuleAssertThat(code).hasNoLintViolations()
     }
+
+    @Test
+    fun `Issue 2694 - Given a call expression with an anonymous function as argument`() {
+        val code =
+            """
+            val foo1 =
+                foo(
+                    fun() = 42,
+                )
+
+            val foo2 = foo(fun() = 42)
+            """.trimIndent()
+        blankLineBeforeDeclarationRuleAssertThat(code).hasNoLintViolations()
+    }
 }