"Receiver parameter is never used" inspection: don't report it when anonymous function is called with receiver

#KT-41246 Fixed

idea/src/org/jetbrains/kotlin/idea/inspections/UnusedReceiverParameterInspection.kt

@@ -6,7 +6,6 @@
 package org.jetbrains.kotlin.idea.inspections
 
 import com.intellij.codeInsight.FileModificationService
-import com.intellij.codeInsight.daemon.impl.HighlightInfoType
 import com.intellij.codeInspection.*
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiElement
@@ -18,6 +17,7 @@ import org.jetbrains.kotlin.idea.KotlinBundle
 import org.jetbrains.kotlin.idea.caches.resolve.analyzeWithContent
 import org.jetbrains.kotlin.idea.caches.resolve.resolveToDescriptorIfAny
 import org.jetbrains.kotlin.idea.core.isOverridable
+import org.jetbrains.kotlin.idea.intentions.callExpression
 import org.jetbrains.kotlin.idea.isMainFunction
 import org.jetbrains.kotlin.idea.quickfix.RemoveUnusedFunctionParameterFix
 import org.jetbrains.kotlin.idea.refactoring.changeSignature.KotlinChangeSignatureConfiguration
@@ -32,6 +32,7 @@ import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.anyDescendantOfType
 import org.jetbrains.kotlin.psi.psiUtil.forEachDescendantOfType
+import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.hasActualModifier
 import org.jetbrains.kotlin.psi.typeRefHelpers.setReceiverTypeReference
 import org.jetbrains.kotlin.resolve.BindingContext
@@ -49,7 +50,13 @@ class UnusedReceiverParameterInspection : AbstractKotlinInspection() {
                 if (receiverTypeReference == null || receiverTypeReference.textRange.isEmpty) return
 
                 if (callableDeclaration is KtProperty && callableDeclaration.accessors.isEmpty()) return
-                if (callableDeclaration is KtNamedFunction && !callableDeclaration.hasBody()) return
+                if (callableDeclaration is KtNamedFunction) {
+                    if (!callableDeclaration.hasBody()) return
+                    if (callableDeclaration.name == null) {
+                        val parentQualified = callableDeclaration.getStrictParentOfType<KtQualifiedExpression>()
+                        if (KtPsiUtil.deparenthesize(parentQualified?.callExpression?.calleeExpression) == callableDeclaration) return
+                    }
+                }
 
                 if (callableDeclaration.hasModifier(KtTokens.OVERRIDE_KEYWORD) ||
                     callableDeclaration.hasModifier(KtTokens.OPERATOR_KEYWORD) ||

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunction.kt

@@ -0,0 +1,6 @@
+class A {
+    fun a() {
+        val f = fun <caret>A.() {
+        }
+    }
+}

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunction.kt.after

@@ -0,0 +1,6 @@
+class A {
+    fun a() {
+        val f = fun() {
+        }
+    }
+}

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCall.kt

@@ -0,0 +1,6 @@
+class A {
+    fun a() {
+        (fun <caret>A.() {
+        })()
+    }
+}

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCall.kt.after

@@ -0,0 +1,6 @@
+class A {
+    fun a() {
+        (fun() {
+        })()
+    }
+}

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCallWithReceiver.kt

@@ -0,0 +1,7 @@
+// PROBLEM: none
+class A {
+    fun a() {
+        this.(fun <caret>A.() {
+        })()
+    }
+}

idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCallWithReceiver2.kt

@@ -0,0 +1,7 @@
+// PROBLEM: none
+class A
+
+fun test(a: A) {
+    a.(fun <caret>A.() {
+    })()
+}

idea/tests/org/jetbrains/kotlin/idea/inspections/LocalInspectionTestGenerated.java

@@ -14250,6 +14250,26 @@ public class LocalInspectionTestGenerated extends AbstractLocalInspectionTest {
             KotlinTestUtils.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("idea/testData/inspectionsLocal/unusedReceiverParameter"), Pattern.compile("^([\\w\\-_]+)\\.(kt|kts)$"), null, true);
         }
 
+        @TestMetadata("anonymousFunction.kt")
+        public void testAnonymousFunction() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunction.kt");
+        }
+
+        @TestMetadata("anonymousFunctionCall.kt")
+        public void testAnonymousFunctionCall() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCall.kt");
+        }
+
+        @TestMetadata("anonymousFunctionCallWithReceiver.kt")
+        public void testAnonymousFunctionCallWithReceiver() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCallWithReceiver.kt");
+        }
+
+        @TestMetadata("anonymousFunctionCallWithReceiver2.kt")
+        public void testAnonymousFunctionCallWithReceiver2() throws Exception {
+            runTest("idea/testData/inspectionsLocal/unusedReceiverParameter/anonymousFunctionCallWithReceiver2.kt");
+        }
+
         @TestMetadata("companion.kt")
         public void testCompanion() throws Exception {
             runTest("idea/testData/inspectionsLocal/unusedReceiverParameter/companion.kt");