support quick doc for completion items

#KT-4346 Fixed

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

@@ -16,30 +16,30 @@
 
 package org.jetbrains.kotlin.idea.completion
 
-import com.intellij.codeInsight.completion.CompletionResultSet
 import com.intellij.codeInsight.completion.CompletionParameters
+import com.intellij.codeInsight.completion.CompletionResultSet
 import com.intellij.codeInsight.completion.CompletionSorter
-import org.jetbrains.kotlin.psi.JetFile
-import com.intellij.codeInsight.lookup.LookupElementWeigher
-import com.intellij.codeInsight.lookup.LookupElement
-import com.intellij.codeInsight.lookup.WeighingContext
-import org.jetbrains.kotlin.idea.completion.*
-import org.jetbrains.kotlin.descriptors.PackageViewDescriptor
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
-import org.jetbrains.kotlin.resolve.DescriptorUtils
-import org.jetbrains.kotlin.name.isValidJavaFqName
-import org.jetbrains.kotlin.resolve.ImportPath
 import com.intellij.codeInsight.completion.CompletionType
+import com.intellij.codeInsight.lookup.LookupElement
+import com.intellij.codeInsight.lookup.LookupElementWeigher
+import com.intellij.codeInsight.lookup.WeighingContext
+import com.intellij.psi.PsiClass
+import org.jetbrains.kotlin.builtins.KotlinBuiltIns
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.PackageViewDescriptor
+import org.jetbrains.kotlin.descriptors.VariableDescriptor
 import org.jetbrains.kotlin.idea.completion.smart.NameSimilarityWeigher
 import org.jetbrains.kotlin.idea.completion.smart.SMART_COMPLETION_ITEM_PRIORITY_KEY
 import org.jetbrains.kotlin.idea.completion.smart.SmartCompletionItemPriority
-import com.intellij.psi.PsiClass
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
-import java.util.HashSet
-import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.platform.JavaToKotlinClassMap
 import org.jetbrains.kotlin.idea.util.ImportInsertHelper
-import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.name.FqName
-import org.jetbrains.kotlin.descriptors.VariableDescriptor
+import org.jetbrains.kotlin.name.isValidJavaFqName
+import org.jetbrains.kotlin.platform.JavaToKotlinClassMap
+import org.jetbrains.kotlin.psi.JetFile
+import org.jetbrains.kotlin.resolve.DescriptorUtils
+import org.jetbrains.kotlin.resolve.ImportPath
+import java.util.HashSet
 
 public fun CompletionResultSet.addKotlinSorting(parameters: CompletionParameters): CompletionResultSet {
     var sorter = CompletionSorter.defaultSorter(parameters, getPrefixMatcher())!!
@@ -89,7 +89,7 @@ private object KindWeigher : LookupElementWeigher("kotlin.kind") {
         val o = element.getObject()
 
         return when (o) {
-            is DeclarationDescriptorLookupObject -> {
+            is DeclarationDescriptorLookupObjectImpl -> {
                 val descriptor = o.descriptor
                 when (descriptor) {
                     is VariableDescriptor -> CompoundWeight(Weight.variable, element.getUserData(CALLABLE_WEIGHT_KEY))
@@ -136,7 +136,7 @@ private class JetDeclarationRemotenessWeigher(private val file: JetFile) : Looku
 
     override fun weigh(element: LookupElement): Weight {
         val o = element.getObject()
-        if (o is DeclarationDescriptorLookupObject) {
+        if (o is DeclarationDescriptorLookupObjectImpl) {
             val elementFile = o.psiElement?.getContainingFile()
             if (elementFile is JetFile && elementFile.getOriginalFile() == file) {
                 return Weight.thisFile

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

@@ -20,16 +20,17 @@ import com.intellij.openapi.diagnostic.Logger
 import com.intellij.psi.PsiElement
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.ResolutionFacade
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
 
 /**
  * Stores information about resolved descriptor and position of that descriptor.
  * Position will be used for sorting
  */
-public class DeclarationDescriptorLookupObject(
+public class DeclarationDescriptorLookupObjectImpl(
-        public val descriptor: DeclarationDescriptor,
+        public override val descriptor: DeclarationDescriptor,
         private val resolutionFacade: ResolutionFacade,
-        public val psiElement: PsiElement?
+        public override val psiElement: PsiElement?
-) {
+): DeclarationDescriptorLookupObject {
     override fun toString(): String {
         return super.toString() + " " + descriptor
     }
@@ -42,7 +43,7 @@ public class DeclarationDescriptorLookupObject(
         if (this identityEquals other) return true
         if (other == null || javaClass != other.javaClass) return false
 
-        val lookupObject = other as DeclarationDescriptorLookupObject
+        val lookupObject = other as DeclarationDescriptorLookupObjectImpl
 
         if (resolutionFacade != lookupObject.resolutionFacade) {
             LOG.warn("Descriptors from different resolve sessions")

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

@@ -154,7 +154,7 @@ public class LookupElementFactory(
         val name = nameAndIconDescriptor.getName().asString()
         val icon = JetDescriptorIconProvider.getIcon(nameAndIconDescriptor, iconDeclaration, Iconable.ICON_FLAG_VISIBILITY)
 
-        var element = LookupElementBuilder.create(DeclarationDescriptorLookupObject(descriptor, resolutionFacade, declaration), name)
+        var element = LookupElementBuilder.create(DeclarationDescriptorLookupObjectImpl(descriptor, resolutionFacade, declaration), name)
                 .withIcon(icon)
 
         when (descriptor) {

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/handlers/BaseDeclarationInsertHandler.kt

@@ -17,10 +17,10 @@
 package org.jetbrains.kotlin.idea.completion.handlers
 
 import com.intellij.codeInsight.completion.InsertHandler
-import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.codeInsight.completion.InsertionContext
-import org.jetbrains.kotlin.idea.completion.DeclarationDescriptorLookupObject
+import com.intellij.codeInsight.lookup.LookupElement
 import com.intellij.openapi.util.TextRange
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 
 open class BaseDeclarationInsertHandler : InsertHandler<LookupElement> {

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/handlers/KotlinCallableInsertHandler.kt

@@ -28,8 +28,8 @@ import com.intellij.psi.PsiElement
 import com.intellij.psi.codeStyle.CodeStyleSettingsManager
 import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
-import org.jetbrains.kotlin.idea.completion.DeclarationDescriptorLookupObject
 import org.jetbrains.kotlin.idea.completion.isAfterDot
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
 import org.jetbrains.kotlin.idea.core.formatter.JetCodeStyleSettings
 import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 import org.jetbrains.kotlin.idea.util.ImportInsertHelper

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/handlers/KotlinClassInsertHandler.kt

@@ -18,18 +18,18 @@ package org.jetbrains.kotlin.idea.completion.handlers
 
 import com.intellij.codeInsight.completion.InsertionContext
 import com.intellij.codeInsight.lookup.LookupElement
-import com.intellij.psi.PsiDocumentManager
-import org.jetbrains.kotlin.psi.JetFile
-import org.jetbrains.kotlin.idea.util.ShortenReferences
-import org.jetbrains.kotlin.idea.completion.DeclarationDescriptorLookupObject
-import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import com.intellij.psi.PsiClass
-import org.jetbrains.kotlin.psi.JetNameReferenceExpression
+import com.intellij.psi.PsiDocumentManager
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
+import org.jetbrains.kotlin.idea.completion.isAfterDot
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
+import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
+import org.jetbrains.kotlin.idea.util.ShortenReferences
+import org.jetbrains.kotlin.psi.JetFile
+import org.jetbrains.kotlin.psi.JetNameReferenceExpression
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
-import org.jetbrains.kotlin.idea.completion.isAfterDot
-import org.jetbrains.kotlin.idea.util.IdeDescriptorRenderers
 
 public object KotlinClassInsertHandler : BaseDeclarationInsertHandler() {
     override fun handleInsert(context: InsertionContext, item: LookupElement) {

idea/idea-core/src/org/jetbrains/kotlin/idea/core/completion/DeclarationDescriptorLookupObject.kt

@@ -0,0 +1,25 @@
+/*
+ * 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.core.completion
+
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+
+public trait DeclarationDescriptorLookupObject {
+    public val psiElement: PsiElement?
+    public val descriptor: DeclarationDescriptor
+}

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

@@ -27,6 +27,7 @@ import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorWithSource
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
+import org.jetbrains.kotlin.idea.core.completion.DeclarationDescriptorLookupObject
 import org.jetbrains.kotlin.idea.kdoc.KDocFinder
 import org.jetbrains.kotlin.idea.kdoc.KDocRenderer
 import org.jetbrains.kotlin.idea.kdoc.resolveKDocLink
@@ -71,6 +72,13 @@ public class KotlinQuickDocumentationProvider : AbstractDocumentationProvider()
         return null
     }
 
+    override fun getDocumentationElementForLookupItem(psiManager: PsiManager, `object`: Any?, element: PsiElement?): PsiElement? {
+        if (`object` is DeclarationDescriptorLookupObject) {
+            return `object`.psiElement
+        }
+        return null
+    }
+
     companion object {
         private val LOG = Logger.getInstance(javaClass<KotlinQuickDocumentationProvider>())
 

idea/testData/kdoc/inCompletion/simple.kt

@@ -0,0 +1,11 @@
+class Xyzzy {
+
+}
+
+class Xyzzy2 {
+
+}
+
+fun foo() {
+    val x = Xy<caret>
+}

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

@@ -0,0 +1,38 @@
+/*
+ * 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.testFramework.fixtures.LightPlatformCodeInsightFixtureTestCase
+import org.jetbrains.kotlin.idea.JetFileType
+import org.jetbrains.kotlin.idea.KotlinQuickDocumentationProvider
+import org.jetbrains.kotlin.idea.test.PluginTestCaseBase
+import org.jetbrains.kotlin.psi.JetClass
+import org.junit.Assert
+
+public class QuickDocInCompletionTest(): LightPlatformCodeInsightFixtureTestCase() {
+    override fun getTestDataPath(): String {
+        return PluginTestCaseBase.getTestDataPathBase() + "/kdoc/inCompletion/"
+    }
+    public fun testSimple() {
+        myFixture.configureByFile(getTestName(true) + ".kt")
+        val lookupElements = myFixture.completeBasic()
+        val lookupObject = lookupElements.first().getObject()
+        val element = KotlinQuickDocumentationProvider().getDocumentationElementForLookupItem(
+                myFixture.getPsiManager(), lookupObject, null)
+        Assert.assertTrue(element is JetClass)
+    }
+}