getModuleInfo: Correct module info for members of light classes for decompiled Kotlin classes

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

@@ -28,6 +28,8 @@ import com.intellij.openapi.project.Project
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.openapi.roots.ModuleRootManager
 import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
+import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
+import org.jetbrains.kotlin.utils.sure
 
 fun PsiElement.getModuleInfo(): IdeaModuleInfo {
     fun logAndReturnDefault(message: String): IdeaModuleInfo {
@@ -115,8 +117,13 @@ private fun getModuleInfoByVirtualFile(project: Project, virtualFile: VirtualFil
 }
 
 private fun KtLightElement<*, *>.getModuleInfoForLightElement(): IdeaModuleInfo {
-    if (this is KtLightClassForDecompiledDeclaration) {
+    val decompiledClass = this.getParentOfType<KtLightClassForDecompiledDeclaration>(strict = false)
-        return getModuleInfoByVirtualFile(getProject(), getContainingFile().getVirtualFile(), false)
+    if (decompiledClass != null) {
+        return getModuleInfoByVirtualFile(
+                project,
+                containingFile.virtualFile.sure { "Decompiled class should be build from physical file" },
+                false
+        )
     }
     val element = getOrigin() ?: when (this) {
         is FakeLightClassForFileOfPackage -> this.getContainingFile()!!

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

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2010-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.idea.caches.resolve
+
+import com.intellij.psi.JavaPsiFacade
+import com.intellij.psi.search.GlobalSearchScope
+import org.jetbrains.kotlin.idea.test.KotlinLightCodeInsightFixtureTestCase
+import org.jetbrains.kotlin.idea.test.KotlinWithJdkAndRuntimeLightProjectDescriptor
+import org.junit.Assert
+
+public class CustomModuleInfoTest : KotlinLightCodeInsightFixtureTestCase() {
+    override fun getProjectDescriptor() = KotlinWithJdkAndRuntimeLightProjectDescriptor.INSTANCE
+
+    fun testModuleInfoForMembersOfLightClassForDecompiledFile() {
+        //NOTE: any class with methods from stdlib will do
+        val collectionsKtClass = JavaPsiFacade.getInstance(project).findClass("kotlin.CollectionsKt", GlobalSearchScope.allScope(project))!!
+        val classModuleInfo = collectionsKtClass.getModuleInfo()
+        Assert.assertTrue(classModuleInfo is LibraryInfo)
+        val methods = collectionsKtClass.methods
+        Assert.assertTrue(methods.isNotEmpty())
+        methods.forEach {
+            Assert.assertEquals("Members of decompiled class should have the same module info", classModuleInfo, it.getModuleInfo())
+        }
+    }
+}