From 2239b9a98a510ed87b46fb6e615b86105d916250 Mon Sep 17 00:00:00 2001
From: Toshiaki Kameyama <kmymtsak@gmail.com>
Date: Wed, 5 Oct 2022 10:04:24 +0900
Subject: [PATCH] UnusedPrivateMember: fix false negative with named arguments

---
 .../detekt/rules/style/UnusedPrivateMember.kt |  5 ++-
 .../rules/style/UnusedPrivateMemberSpec.kt    | 32 +++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMember.kt b/detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMember.kt
index eaf21701784e..ee5effeed4f8 100644
--- a/detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMember.kt
+++ b/detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMember.kt
@@ -39,6 +39,7 @@ import org.jetbrains.kotlin.psi.KtProperty
 import org.jetbrains.kotlin.psi.KtPropertyDelegate
 import org.jetbrains.kotlin.psi.KtReferenceExpression
 import org.jetbrains.kotlin.psi.KtSecondaryConstructor
+import org.jetbrains.kotlin.psi.KtValueArgumentName
 import org.jetbrains.kotlin.psi.psiUtil.containingClassOrObject
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.isPrivate
@@ -258,7 +259,9 @@ private class UnusedParameterVisitor(allowedNames: Regex) : UnusedMemberVisitor(
             }
 
             override fun visitReferenceExpression(expression: KtReferenceExpression) {
-                parameters.remove(expression.text.removeSurrounding("`"))
+                if (expression.parent !is KtValueArgumentName) {
+                    parameters.remove(expression.text.removeSurrounding("`"))
+                }
                 super.visitReferenceExpression(expression)
             }
         })
diff --git a/detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMemberSpec.kt b/detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMemberSpec.kt
index 62812d702259..d28b1a150e5f 100644
--- a/detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMemberSpec.kt
+++ b/detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/UnusedPrivateMemberSpec.kt
@@ -1648,4 +1648,36 @@ class UnusedPrivateMemberSpec(val env: KotlinCoreEnvironment) {
             assertThat(subject.lint(code)).hasSize(1).hasStartSourceLocation(6, 9)
         }
     }
+
+    @Nested
+    inner class `parameter with the same name as a named argument #5373` {
+        @Test
+        fun `unused parameter`() {
+            val code = """
+                fun foo(modifier: Int) {
+                    bar(modifier = 1)
+                }
+                
+                fun bar(modifier: Int) {
+                    println(modifier)
+                }
+            """.trimIndent()
+            assertThat(subject.compileAndLintWithContext(env, code))
+                .hasSize(1).hasStartSourceLocation(1, 9)
+        }
+
+        @Test
+        fun `used parameter`() {
+            val code = """
+                fun foo(modifier: Int) {
+                    bar(modifier = modifier)
+                }
+                
+                fun bar(modifier: Int) {
+                    println(modifier)
+                }
+            """.trimIndent()
+            assertThat(subject.compileAndLintWithContext(env, code)).isEmpty()
+        }
+    }
 }