KT-18538 Unwrap fake override in ShortenReferences

- Fake override prevents reference shortener from shortening of static
methods declared in the class bases when they are located not in
direct parent of the class (for example, in grand-
or grand-grand-parent)
- The completion uses descriptor with unwrapped fake override when it
performs the insertion. It leads to inserting the name of the base which
actually contains the static method instead of the direct parent class.
Now, when reference shortener compares unwrapped descriptors, this
problem should be fixed during insertion handling

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/BasicLookupElementFactory.kt

@@ -19,6 +19,7 @@ import org.jetbrains.kotlin.idea.completion.handlers.KotlinClassifierInsertHandl
 import org.jetbrains.kotlin.idea.completion.handlers.KotlinFunctionInsertHandler
 import org.jetbrains.kotlin.idea.core.completion.DeclarationLookupObject
 import org.jetbrains.kotlin.idea.core.completion.PackageLookupObject
+import org.jetbrains.kotlin.idea.core.unwrapIfFakeOverride
 import org.jetbrains.kotlin.idea.highlighter.dsl.DslHighlighterExtension
 import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.load.java.descriptors.JavaClassDescriptor
@@ -51,10 +52,7 @@ class BasicLookupElementFactory(
         includeClassTypeArguments: Boolean = true,
         parametersAndTypeGrayed: Boolean = false
     ): LookupElement {
-        val _descriptor = if (descriptor is CallableMemberDescriptor)
-            DescriptorUtils.unwrapFakeOverride(descriptor)
-        else
-            descriptor
+        val _descriptor = descriptor.unwrapIfFakeOverride()
         return createLookupElementUnwrappedDescriptor(_descriptor, qualifyNestedClasses, includeClassTypeArguments, parametersAndTypeGrayed)
     }
 

idea/idea-completion/testData/handlers/multifile/StaticMethodFromGrandParent-1.java

@@ -0,0 +1,2 @@
+public class Base extends GrandBase {
+}

idea/idea-completion/testData/handlers/multifile/StaticMethodFromGrandParent-1.kt

@@ -0,0 +1,5 @@
+class Inheritor : Base() {
+    init {
+        fooBa<caret>
+    }
+}

idea/idea-completion/testData/handlers/multifile/StaticMethodFromGrandParent-2.java

@@ -0,0 +1,3 @@
+public class GrandBase {
+    public static void fooBar() {}
+}

idea/idea-completion/testData/handlers/multifile/StaticMethodFromGrandParent.kt.after

@@ -0,0 +1,5 @@
+class Inheritor : Base() {
+    init {
+        fooBar()
+    }
+}

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/handlers/CompletionMultifileHandlerTest.kt

@@ -30,6 +30,10 @@ class CompletionMultiFileHandlerTest : KotlinCompletionTestCase() {
         doTest()
     }
 
+    fun testStaticMethodFromGrandParent() {
+        doTest('\n', "StaticMethodFromGrandParent-1.java", "StaticMethodFromGrandParent-2.java")
+    }
+
     fun testTopLevelFunctionImport() {
         doTest()
     }
@@ -113,8 +117,13 @@ class CompletionMultiFileHandlerTest : KotlinCompletionTestCase() {
     fun doTest(completionChar: Char = '\n', vararg extraFileNames: String, tailText: String? = null) {
         val fileName = getTestName(false)
 
+        val defaultFiles = listOf("$fileName-1.kt", "$fileName-2.kt")
+        val filteredFiles = defaultFiles.filter { File(testDataPath, it).exists() }
+
+        require(filteredFiles.isNotEmpty()) { "At least one of $defaultFiles should exist!" }
+
         configureByFiles(null, *extraFileNames)
-        configureByFiles(null, "$fileName-1.kt", "$fileName-2.kt")
+        configureByFiles(null, *filteredFiles.toTypedArray())
         complete(2)
         if (myItems != null) {
             val item = if (tailText == null)

idea/idea-core/src/org/jetbrains/kotlin/idea/core/ShortenReferences.kt

@@ -552,7 +552,10 @@ class ShortenReferences(val options: (KtElement) -> Options = { Options.DEFAULT
             // targetMatch == false, but shorten still can be preformed
             // TODO: Add possibility to check if descriptor from completion can't be resolved after shorten and not preform shorten than
             val resolvedCallsMatch = if (resolvedCall != null && resolvedCallWhenShort != null) {
-                resolvedCall.resultingDescriptor.original == resolvedCallWhenShort.resultingDescriptor.original
+                val originalCallDescriptor = resolvedCall.resultingDescriptor.original.unwrapIfFakeOverride()
+                val shortenedCallDescriptor = resolvedCallWhenShort.resultingDescriptor.original.unwrapIfFakeOverride()
+
+                originalCallDescriptor == shortenedCallDescriptor
             } else {
                 val resolvedCalls = selector.getCall(bindingContext)?.resolveCandidates(bindingContext, resolutionFacade) ?: emptyList()
                 val callWhenShort = selectorAfterShortening.getCall(newContext)

idea/idea-core/src/org/jetbrains/kotlin/idea/core/descriptorUtils.kt

@@ -141,3 +141,7 @@ fun <D : CallableMemberDescriptor> D.getDeepestSuperDeclarations(withThis: Boole
 
     return overriddenDeclarations.filterNot(DescriptorUtils::isOverride)
 }
+
+fun <T : DeclarationDescriptor> T.unwrapIfFakeOverride(): T {
+    return if (this is CallableMemberDescriptor) DescriptorUtils.unwrapFakeOverride(this) else this
+}

idea/src/org/jetbrains/kotlin/idea/quickfix/replaceWith/ReplaceWithAnnotationAnalyzer.kt

@@ -12,6 +12,7 @@ import org.jetbrains.kotlin.idea.analysis.analyzeInContext
 import org.jetbrains.kotlin.idea.caches.resolve.resolveImportReference
 import org.jetbrains.kotlin.idea.codeInliner.CodeToInline
 import org.jetbrains.kotlin.idea.codeInliner.CodeToInlineBuilder
+import org.jetbrains.kotlin.idea.core.unwrapIfFakeOverride
 import org.jetbrains.kotlin.idea.project.findAnalyzerServices
 import org.jetbrains.kotlin.idea.references.KtSimpleNameReference
 import org.jetbrains.kotlin.idea.references.mainReference
@@ -43,10 +44,7 @@ object ReplaceWithAnnotationAnalyzer {
         resolutionFacade: ResolutionFacade,
         reformat: Boolean
     ): CodeToInline? {
-        val originalDescriptor = when (symbolDescriptor) {
-            is CallableMemberDescriptor -> DescriptorUtils.unwrapFakeOverride(symbolDescriptor)
-            else -> symbolDescriptor
-        }.original
+        val originalDescriptor = symbolDescriptor.unwrapIfFakeOverride().original
         return analyzeOriginal(annotation, originalDescriptor, resolutionFacade, reformat)
     }
 

idea/testData/shortenRefs/java/redundantGrandParentClassQualifier.dependency.java

@@ -0,0 +1,7 @@
+public class Container {
+    public static class GrandBase {
+        public static void foo() {}
+    }
+
+    public static class Base extends GrandBase {}
+}

idea/testData/shortenRefs/java/redundantGrandParentClassQualifier.kt

@@ -0,0 +1,5 @@
+class C : Container.Base() {
+    init {
+        <selection>Container.GrandBase.foo()</selection>
+    }
+}

idea/testData/shortenRefs/java/redundantGrandParentClassQualifier.kt.after

@@ -0,0 +1,5 @@
+class C : Container.Base() {
+    init {
+        foo()
+    }
+}

idea/testData/shortenRefs/java/redundantGrandParentClassQualifierAmbiguous.dependency.java

@@ -0,0 +1,9 @@
+public class Container {
+    public static class GrandBase {
+        public static void foo() {}
+    }
+
+    public static class Base extends GrandBase {
+        public static void foo() {}
+    }
+}

idea/testData/shortenRefs/java/redundantGrandParentClassQualifierAmbiguous.kt

@@ -0,0 +1,5 @@
+class C : Container.Base() {
+    init {
+        <selection>Container.GrandBase.foo()</selection>
+    }
+}

idea/testData/shortenRefs/java/redundantGrandParentClassQualifierAmbiguous.kt.after

@@ -0,0 +1,5 @@
+class C : Container.Base() {
+    init {
+        Container.GrandBase.foo()
+    }
+}

idea/tests/org/jetbrains/kotlin/shortenRefs/ShortenRefsTestGenerated.java

@@ -301,6 +301,16 @@ public class ShortenRefsTestGenerated extends AbstractShortenRefsTest {
             runTest("idea/testData/shortenRefs/java/innerClassOnDemandImport.kt");
         }
 
+        @TestMetadata("redundantGrandParentClassQualifier.kt")
+        public void testRedundantGrandParentClassQualifier() throws Exception {
+            runTest("idea/testData/shortenRefs/java/redundantGrandParentClassQualifier.kt");
+        }
+
+        @TestMetadata("redundantGrandParentClassQualifierAmbiguous.kt")
+        public void testRedundantGrandParentClassQualifierAmbiguous() throws Exception {
+            runTest("idea/testData/shortenRefs/java/redundantGrandParentClassQualifierAmbiguous.kt");
+        }
+
         @TestMetadata("staticClassNoImports.kt")
         public void testStaticClassNoImports() throws Exception {
             runTest("idea/testData/shortenRefs/java/staticClassNoImports.kt");