Find usages and reference to delegation origin

compiler/backend/src/org/jetbrains/kotlin/codegen/FunctionCodegen.java

@@ -42,6 +42,7 @@ import org.jetbrains.kotlin.name.FqName;
 import org.jetbrains.kotlin.psi.JetClassOrObject;
 import org.jetbrains.kotlin.psi.JetNamedFunction;
 import org.jetbrains.kotlin.resolve.BindingContext;
+import org.jetbrains.kotlin.resolve.DescriptorToSourceUtils;
 import org.jetbrains.kotlin.resolve.DescriptorUtils;
 import org.jetbrains.kotlin.resolve.annotations.AnnotationsPackage;
 import org.jetbrains.kotlin.resolve.calls.CallResolverUtil;
@@ -76,7 +77,9 @@ import static org.jetbrains.kotlin.resolve.DescriptorToSourceUtils.callableDescr
 import static org.jetbrains.kotlin.resolve.DescriptorUtils.isFunctionLiteral;
 import static org.jetbrains.kotlin.resolve.DescriptorUtils.isTrait;
 import static org.jetbrains.kotlin.resolve.jvm.AsmTypes.OBJECT_TYPE;
-import static org.jetbrains.kotlin.resolve.jvm.diagnostics.DiagnosticsPackage.*;
+import static org.jetbrains.kotlin.resolve.jvm.diagnostics.DiagnosticsPackage.Delegation;
+import static org.jetbrains.kotlin.resolve.jvm.diagnostics.DiagnosticsPackage.OtherOrigin;
+import static org.jetbrains.kotlin.resolve.jvm.diagnostics.DiagnosticsPackage.Synthetic;
 import static org.jetbrains.org.objectweb.asm.Opcodes.*;
 
 public class FunctionCodegen {
@@ -836,7 +839,7 @@ public class FunctionCodegen {
             final StackValue field
     ) {
         generateMethod(
-                Delegation(null, delegateFunction), delegateFunction,
+                Delegation(DescriptorToSourceUtils.descriptorToDeclaration(delegatedTo), delegateFunction), delegateFunction,
                 new FunctionGenerationStrategy() {
                     @Override
                     public void generateBody(

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitImplThroughDelegate.0.kt

@@ -0,0 +1,11 @@
+// PSI_ELEMENT: org.jetbrains.kotlin.psi.JetNamedFunction
+// OPTIONS: usages, skipImports
+package server
+
+trait TraitWithImpl {
+    fun <caret>foo() = 1
+}
+
+public class TraitWithDelegatedWithImpl(f: TraitWithImpl): TraitWithImpl by f
+
+fun test(twdwi: TraitWithDelegatedWithImpl) = twdwi.foo()

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitImplThroughDelegate.1.java

@@ -0,0 +1,9 @@
+package client;
+
+import server.TraitWithDelegatedWithImpl;
+
+public class Test {
+    public static void bar(TraitWithDelegatedWithImpl some) {
+        some.foo();
+    }
+}

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitImplThroughDelegate.results.txt

@@ -0,0 +1,2 @@
+Function call (11: 53) fun test(twdwi: TraitWithDelegatedWithImpl) = twdwi.foo()
+Unclassified usage (7: 14) some.foo();

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitNoImplThroughDelegate.0.kt

@@ -0,0 +1,11 @@
+// PSI_ELEMENT: org.jetbrains.kotlin.psi.JetNamedFunction
+// OPTIONS: usages, skipImports
+package server
+
+trait TraitNoImpl {
+    fun <caret>foo()
+}
+
+public class TraitWithDelegatedNoImpl(f: TraitNoImpl): TraitNoImpl by f
+
+fun test(twdni: TraitWithDelegatedNoImpl) = twdni.foo()

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitNoImplThroughDelegate.1.java

@@ -0,0 +1,9 @@
+package client;
+
+import server.TraitWithDelegatedNoImpl;
+
+public class JClient {
+    public static void bar(TraitWithDelegatedNoImpl some) {
+        some.foo();
+    }
+}

idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitNoImplThroughDelegate.results.txt

@@ -0,0 +1,2 @@
+Function call (11: 51) fun test(twdni: TraitWithDelegatedNoImpl) = twdni.foo()
+Unclassified usage (7: 14) some.foo();

idea/testData/resolve/referenceInJava/DelegatedMethodFromTraitNoImpl.java

@@ -0,0 +1,9 @@
+import k.*;
+
+public class Test {
+    public static void bar(TraitWithDelegatedNoImpl some) {
+        some.<caret>foo();
+    }
+}
+
+// REF: (in k.TraitNoImpl).foo()

idea/testData/resolve/referenceInJava/DelegatedMethodFromTraitWithImpl.java

@@ -0,0 +1,9 @@
+import k.*;
+
+public class Test {
+    public static void bar(TraitWithDelegatedWithImpl some) {
+        some.<caret>foo();
+    }
+}
+
+// REF: (in k.TraitWithImpl).foo()

idea/testData/resolve/referenceInJava/dependencies.kt

@@ -39,4 +39,12 @@ object PlatformStaticFun {
 
 trait TraitNoImpl {
     fun foo()
-}
+}
+
+public class TraitWithDelegatedNoImpl(f: TraitNoImpl): TraitNoImpl by f
+
+trait TraitWithImpl {
+    fun foo() = 1
+}
+
+public class TraitWithDelegatedWithImpl(f: TraitWithImpl): TraitWithImpl by f

idea/tests/org/jetbrains/kotlin/findUsages/JetFindUsagesTestGenerated.java

@@ -556,6 +556,18 @@ public class JetFindUsagesTestGenerated extends AbstractJetFindUsagesTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("kotlinTraitImplThroughDelegate.0.kt")
+            public void testKotlinTraitImplThroughDelegate() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitImplThroughDelegate.0.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("kotlinTraitNoImplThroughDelegate.0.kt")
+            public void testKotlinTraitNoImplThroughDelegate() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/findFunctionUsages/kotlinTraitNoImplThroughDelegate.0.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("synthesizedFunction.0.kt")
             public void testSynthesizedFunction() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("idea/testData/findUsages/kotlin/findFunctionUsages/synthesizedFunction.0.kt");

idea/tests/org/jetbrains/kotlin/idea/resolve/ReferenceResolveInJavaTestGenerated.java

@@ -60,6 +60,18 @@ public class ReferenceResolveInJavaTestGenerated extends AbstractReferenceResolv
         doTest(fileName);
     }
 
+    @TestMetadata("DelegatedMethodFromTraitNoImpl.java")
+    public void testDelegatedMethodFromTraitNoImpl() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/resolve/referenceInJava/DelegatedMethodFromTraitNoImpl.java");
+        doTest(fileName);
+    }
+
+    @TestMetadata("DelegatedMethodFromTraitWithImpl.java")
+    public void testDelegatedMethodFromTraitWithImpl() throws Exception {
+        String fileName = JetTestUtils.navigationMetadata("idea/testData/resolve/referenceInJava/DelegatedMethodFromTraitWithImpl.java");
+        doTest(fileName);
+    }
+
     @TestMetadata("DeprecatedClassObjectField.java")
     public void testDeprecatedClassObjectField() throws Exception {
         String fileName = JetTestUtils.navigationMetadata("idea/testData/resolve/referenceInJava/DeprecatedClassObjectField.java");