KotlinQuickDocumentationProvider: fix quick doc for elements from type hierarchy

Fix quick doc for light classes

 #KT-7964 Fixed

idea/src/org/jetbrains/kotlin/idea/KotlinQuickDocumentationProvider.kt

@@ -22,6 +22,7 @@ import com.intellij.openapi.diagnostic.Logger
 import com.intellij.openapi.util.text.StringUtil
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiManager
+import org.jetbrains.kotlin.asJava.KotlinLightElement
 import org.jetbrains.kotlin.asJava.KotlinLightMethod
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorWithSource
@@ -33,7 +34,6 @@ import org.jetbrains.kotlin.idea.kdoc.KDocRenderer
 import org.jetbrains.kotlin.idea.kdoc.resolveKDocLink
 import org.jetbrains.kotlin.psi.JetDeclaration
 import org.jetbrains.kotlin.psi.JetElement
-import org.jetbrains.kotlin.psi.JetPsiUtil
 import org.jetbrains.kotlin.psi.JetReferenceExpression
 import org.jetbrains.kotlin.psi.psiUtil.getElementTextWithContext
 import org.jetbrains.kotlin.psi.psiUtil.getNonStrictParentOfType
@@ -50,7 +50,7 @@ public class KotlinQuickDocumentationProvider : AbstractDocumentationProvider()
         return getText(element, originalElement, true)
     }
 
-    override fun generateDoc(element: PsiElement, originalElement: PsiElement): String? {
+    override fun generateDoc(element: PsiElement, originalElement: PsiElement?): String? {
         return getText(element, originalElement, false)
     }
 
@@ -91,18 +91,17 @@ public class KotlinQuickDocumentationProvider : AbstractDocumentationProvider()
                 .build()
 
 
-        private fun getText(element: PsiElement, originalElement: PsiElement, quickNavigation: Boolean): String? {
+        private fun getText(element: PsiElement, originalElement: PsiElement?, quickNavigation: Boolean): String? {
             if (element is JetDeclaration) {
                 return renderKotlinDeclaration(element, quickNavigation)
             }
-            else if (element is KotlinLightMethod) {
+            else if (element is KotlinLightElement<*, *>) {
-                val origin = element.getOrigin()
+                val origin = element.getOrigin() ?: return null
-                if (origin == null) return null
                 return renderKotlinDeclaration(origin, quickNavigation)
             }
 
             if (quickNavigation) {
-                val referenceExpression = originalElement.getNonStrictParentOfType<JetReferenceExpression>()
+                val referenceExpression = originalElement?.getNonStrictParentOfType<JetReferenceExpression>()
                 if (referenceExpression != null) {
                     val context = referenceExpression.analyze(BodyResolveMode.PARTIAL)
                     val declarationDescriptor = context[BindingContext.REFERENCE_TARGET, referenceExpression]
@@ -139,7 +138,7 @@ public class KotlinQuickDocumentationProvider : AbstractDocumentationProvider()
             return renderedDecl
         }
 
-        private fun mixKotlinToJava(declarationDescriptor: DeclarationDescriptor, element: PsiElement, originalElement: PsiElement): String? {
+        private fun mixKotlinToJava(declarationDescriptor: DeclarationDescriptor, element: PsiElement, originalElement: PsiElement?): String? {
             val originalInfo = JavaDocumentationProvider().getQuickNavigateInfo(element, originalElement)
             if (originalInfo != null) {
                 val renderedDecl = DescriptorRenderer.HTML_NAMES_WITH_SHORT_TYPES.render(declarationDescriptor)

idea/testData/editor/quickDoc/KotlinClassUsedFromJava.java

@@ -6,4 +6,5 @@ class KotlinClassUsedFromJava {
     }
 }
 
-//INFO: [light_idea_test_case] testing...
+//INFO: <b>internal</b> <b>final</b> <b>class</b> Test <i>defined in</i> testing<br/><p>Some comment
+//INFO: </p>

idea/testData/kdoc/inTypeHierarchy/simple.kt

@@ -0,0 +1,8 @@
+package a.b.c
+
+/**
+ * Very special class
+ */
+class <caret>A {
+
+}

idea/tests/org/jetbrains/kotlin/idea/editor/quickDoc/QuickDocInHierarchyTest.kt

@@ -0,0 +1,57 @@
+/*
+ * 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.editor.quickDoc
+
+import com.intellij.codeInsight.CodeInsightTestCase
+import com.intellij.ide.hierarchy.HierarchyBrowserBaseEx
+import com.intellij.ide.hierarchy.LanguageTypeHierarchy
+import com.intellij.ide.hierarchy.type.TypeHierarchyNodeDescriptor
+import com.intellij.ide.hierarchy.type.TypeHierarchyTreeStructure
+import com.intellij.openapi.actionSystem.CommonDataKeys
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiClass
+import com.intellij.psi.PsiElement
+import com.intellij.testFramework.MapDataContext
+import junit.framework.TestCase
+import org.jetbrains.kotlin.idea.JetLanguage
+import org.jetbrains.kotlin.idea.KotlinQuickDocumentationProvider
+import org.jetbrains.kotlin.idea.test.PluginTestCaseBase
+
+public class QuickDocInHierarchyTest() : CodeInsightTestCase() {
+    override fun getTestDataPath(): String {
+        return PluginTestCaseBase.getTestDataPathBase() + "/kdoc/inTypeHierarchy/"
+    }
+
+    public fun testSimple() {
+        configureByFile(getTestName(true) + ".kt")
+
+        val context = MapDataContext()
+        context.put<Project>(CommonDataKeys.PROJECT, getProject())
+        context.put<Editor>(CommonDataKeys.EDITOR, getEditor())
+
+        val hierarchyTreeStructure = TypeHierarchyTreeStructure(
+                getProject(),
+                LanguageTypeHierarchy.INSTANCE.forLanguage(JetLanguage.INSTANCE).getTarget(context) as PsiClass?,
+                HierarchyBrowserBaseEx.SCOPE_PROJECT
+        )
+        val hierarchyNodeDescriptor = hierarchyTreeStructure.getBaseDescriptor() as TypeHierarchyNodeDescriptor
+        val doc = KotlinQuickDocumentationProvider().generateDoc(hierarchyNodeDescriptor.getPsiClass() as PsiElement, null)!!
+
+        TestCase.assertTrue("Invalid doc\n: $doc", doc.contains("Very special class"))
+    }
+}