From de83ec00698976406f69af2cabb86e0a6487fdbd Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Mon, 15 Sep 2025 22:10:54 +0200
Subject: [PATCH] [kotlin] unused symbol: disable for parameters of anonymous
 functions

- it's not cheap to check if the function has an explicit expected type, k1 ignored parameters anyway

^KTIJ-35651 fixed

GitOrigin-RevId: b1798d0a67e14fbf4abb798168be71848b86d549
---
 .../K2UnusedSymbolHighlightingTestGenerated.java    | 10 ++++++++++
 .../kotlin/idea/highlighting/K2UnusedSymbolUtil.kt  |  3 +++
 .../inspections/LocalInspectionTestGenerated.java   | 10 ++++++++++
 .../unusedSymbol/anonymousFunction.kt               | 13 +++++++++++++
 .../unusedSymbol/anonymousFunction1.kt              |  7 +++++++
 5 files changed, 43 insertions(+)
 create mode 100644 plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt

diff --git a/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2UnusedSymbolHighlightingTestGenerated.java b/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2UnusedSymbolHighlightingTestGenerated.java
index 28305fe34903..aa8d5dda15b8 100644
--- a/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2UnusedSymbolHighlightingTestGenerated.java
+++ b/plugins/kotlin/code-insight/inspections-k2/tests/test/org/jetbrains/kotlin/idea/k2/inspections/tests/K2UnusedSymbolHighlightingTestGenerated.java
@@ -202,6 +202,16 @@ public abstract class K2UnusedSymbolHighlightingTestGenerated extends AbstractK2
             runTest("../../../idea/tests/testData/inspectionsLocal/unusedSymbol/annotationWithUseSiteTarget.kt");
         }
 
+        @TestMetadata("anonymousFunction.kt")
+        public void testAnonymousFunction() throws Exception {
+            runTest("../../../idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt");
+        }
+
+        @TestMetadata("anonymousFunction1.kt")
+        public void testAnonymousFunction1() throws Exception {
+            runTest("../../../idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt");
+        }
+
         @TestMetadata("arrayAccessOperator.kt")
         public void testArrayAccessOperator() throws Exception {
             runTest("../../../idea/tests/testData/inspectionsLocal/unusedSymbol/arrayAccessOperator.kt");
diff --git a/plugins/kotlin/highlighting/highlighting-k2/src/org/jetbrains/kotlin/idea/highlighting/K2UnusedSymbolUtil.kt b/plugins/kotlin/highlighting/highlighting-k2/src/org/jetbrains/kotlin/idea/highlighting/K2UnusedSymbolUtil.kt
index 818c9ec9fba1..6302ff33bad6 100644
--- a/plugins/kotlin/highlighting/highlighting-k2/src/org/jetbrains/kotlin/idea/highlighting/K2UnusedSymbolUtil.kt
+++ b/plugins/kotlin/highlighting/highlighting-k2/src/org/jetbrains/kotlin/idea/highlighting/K2UnusedSymbolUtil.kt
@@ -103,6 +103,9 @@ object K2UnusedSymbolUtil {
                     if (isExpectedOrActual(containingClass)) return false
                 }
             } else if (ownerFunction is KtFunction) {
+                if (ownerFunction.name == null) {
+                    return false
+                }
                 if (ownerFunction.hasModifier(KtTokens.OPERATOR_KEYWORD)) {
                     // operator parameters are hardcoded to be used since they can't be removed at will, because operator convention would break
                     return false
diff --git a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java
index 9473b87c1969..5a511db5d880 100644
--- a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java
+++ b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java
@@ -16610,6 +16610,16 @@ public abstract class LocalInspectionTestGenerated extends AbstractLocalInspecti
                 runTest("testData/inspectionsLocal/unusedSymbol/annotationWithUseSiteTarget.kt");
             }
 
+            @TestMetadata("anonymousFunction.kt")
+            public void testAnonymousFunction() throws Exception {
+                runTest("testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt");
+            }
+
+            @TestMetadata("anonymousFunction1.kt")
+            public void testAnonymousFunction1() throws Exception {
+                runTest("testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt");
+            }
+
             @TestMetadata("arrayAccessOperator.kt")
             public void testArrayAccessOperator() throws Exception {
                 runTest("testData/inspectionsLocal/unusedSymbol/arrayAccessOperator.kt");
diff --git a/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt b/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt
new file mode 100644
index 000000000000..9f477b04b8ea
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction.kt
@@ -0,0 +1,13 @@
+// PROBLEM: none
+// WITH_STDLIB
+fun foo(p: (String) -> Unit) {
+    p("")
+}
+
+fun use() {
+    foo(
+        fun(i<caret>t: String) {
+            print("foo")
+        },
+    )
+}
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt b/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt
new file mode 100644
index 000000000000..9f5118d2869b
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/inspectionsLocal/unusedSymbol/anonymousFunction1.kt
@@ -0,0 +1,7 @@
+// PROBLEM: none
+// WITH_STDLIB
+fun use() {
+    val f = fun(i<caret>t: String) {
+       print("foo")
+    }
+}
\ No newline at end of file