Lazy light classes: can't use laziness for classes with supertypes delegates

compiler/testData/asJava/lightClasses/Delegation.java

@@ -0,0 +1,9 @@
+public final class B implements p.I {
+    private final p.I f;
+
+    public B(@org.jetbrains.annotations.NotNull p.I f) { /* compiled code */ }
+
+    public void f() { /* compiled code */ }
+
+    public void g() { /* compiled code */ }
+}

compiler/testData/asJava/lightClasses/Delegation.kt

@@ -0,0 +1,13 @@
+// p.B
+package p
+
+class B(private val f: I) : I by f {
+}
+
+interface I {
+    fun g()
+
+    fun f()
+}
+
+// LAZINESS:NoLaziness

compiler/tests/org/jetbrains/kotlin/asJava/CompilerLightClassTestGenerated.java

@@ -42,6 +42,12 @@ public class CompilerLightClassTestGenerated extends AbstractCompilerLightClassT
         doTest(fileName);
     }
 
+    @TestMetadata("Delegation.kt")
+    public void testDelegation() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/Delegation.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("DeprecatedEnumEntry.kt")
     public void testDeprecatedEnumEntry() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/DeprecatedEnumEntry.kt");

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/IDELightClassGenerationSupport.kt

@@ -69,10 +69,12 @@ class IDELightClassGenerationSupport(private val project: Project) : LightClassG
             )
         }
         else {
+            val hasDelegatedMembers = classOrObject.superTypeListEntries.any { it is KtDelegatedSuperTypeEntry }
+            val dummyContextProvider = { IDELightClassContexts.lightContextForClassOrObject(classOrObject) }
             LazyLightClassDataHolder.ForClass(
                     builder,
                     exactContextProvider = { IDELightClassContexts.contextForNonLocalClassOrObject(classOrObject) },
-                    dummyContextProvider = { IDELightClassContexts.lightContextForClassOrObject(classOrObject) }
+                    dummyContextProvider = if (!hasDelegatedMembers) dummyContextProvider else null
             )
         }
     }

idea/tests/org/jetbrains/kotlin/idea/caches/resolve/AbstractIdeLightClassTest.kt

@@ -199,6 +199,9 @@ object LightClassLazinessChecker {
         // still running code above to catch possible exceptions
         if (lazinessMode == Mode.NoConsistency) return
 
+        assertEquals(lightClass.clsDelegate.methods.names(), lightClass.methods.names())
+        assertEquals(lightClass.clsDelegate.fields.names(), lightClass.fields.names())
+
         // check collected data against delegates which should contain correct data
         for ((field, lightFieldInfo) in fieldsToInfo) {
             val delegate = (field as KtLightField).clsDelegate
@@ -210,6 +213,8 @@ object LightClassLazinessChecker {
         }
     }
 
+    private fun Array<out PsiMember>.names() = mapTo(LinkedHashSet()) { it.name }
+
     private data class FieldInfo(
             val name: String,
             val modifiers: List<String>

idea/tests/org/jetbrains/kotlin/idea/caches/resolve/IdeCompiledLightClassTestGenerated.java

@@ -42,6 +42,12 @@ public class IdeCompiledLightClassTestGenerated extends AbstractIdeCompiledLight
         doTest(fileName);
     }
 
+    @TestMetadata("Delegation.kt")
+    public void testDelegation() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/Delegation.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("DeprecatedEnumEntry.kt")
     public void testDeprecatedEnumEntry() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/DeprecatedEnumEntry.kt");

idea/tests/org/jetbrains/kotlin/idea/caches/resolve/IdeLightClassTestGenerated.java

@@ -42,6 +42,12 @@ public class IdeLightClassTestGenerated extends AbstractIdeLightClassTest {
         doTest(fileName);
     }
 
+    @TestMetadata("Delegation.kt")
+    public void testDelegation() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/Delegation.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("DeprecatedEnumEntry.kt")
     public void testDeprecatedEnumEntry() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/asJava/lightClasses/DeprecatedEnumEntry.kt");