KT-6079 Show "parameter information" popup for type arguments

#KT-6079 Fixed

core/descriptors/src/org/jetbrains/kotlin/types/TypeUtils.kt

@@ -52,6 +52,7 @@ fun KotlinType.isNothing(): Boolean = KotlinBuiltIns.isNothing(this)
 fun KotlinType.isNullableNothing(): Boolean = KotlinBuiltIns.isNullableNothing(this)
 fun KotlinType.isUnit(): Boolean = KotlinBuiltIns.isUnit(this)
 fun KotlinType.isAnyOrNullableAny(): Boolean = KotlinBuiltIns.isAnyOrNullableAny(this)
+fun KotlinType.isNullableAny(): Boolean = KotlinBuiltIns.isNullableAny(this)
 fun KotlinType.isBoolean(): Boolean = KotlinBuiltIns.isBoolean(this)
 fun KotlinType.isBooleanOrNullableBoolean(): Boolean = KotlinBuiltIns.isBooleanOrNullableBoolean(this)
 

idea/src/META-INF/plugin.xml

@@ -364,6 +364,8 @@
 
     <codeInsight.parameterInfo language="kotlin" implementationClass="org.jetbrains.kotlin.idea.parameterInfo.KotlinFunctionParameterInfoHandler"/>
     <codeInsight.parameterInfo language="kotlin" implementationClass="org.jetbrains.kotlin.idea.parameterInfo.KotlinArrayAccessParameterInfoHandler"/>
+    <codeInsight.parameterInfo language="kotlin" implementationClass="org.jetbrains.kotlin.idea.parameterInfo.KotlinClassTypeArgumentInfoHandler"/>
+    <codeInsight.parameterInfo language="kotlin" implementationClass="org.jetbrains.kotlin.idea.parameterInfo.KotlinFunctionTypeArgumentInfoHandler"/>
 
     <codeInsight.gotoSuper language="kotlin" implementationClass="org.jetbrains.kotlin.idea.codeInsight.GotoSuperActionHandler"/>
     <typeDeclarationProvider implementation="org.jetbrains.kotlin.idea.codeInsight.KotlinTypeDeclarationProvider"/>

idea/src/org/jetbrains/kotlin/idea/editor/KotlinTypedHandler.java

@@ -75,6 +75,7 @@ public class KotlinTypedHandler extends TypedHandlerDelegate {
             case '<':
                 kotlinLTTyped = CodeInsightSettings.getInstance().AUTOINSERT_PAIR_BRACKET &&
                                 LtGtTypingUtils.shouldAutoCloseAngleBracket(editor.getCaretModel().getOffset(), editor);
+                autoPopupParameterInfo(project, editor);
                 return Result.CONTINUE;
 
             case '>':

idea/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinTypeArgumentInfoHandler.kt

@@ -0,0 +1,217 @@
+/*
+ * Copyright 2010-2016 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.parameterInfo
+
+import com.intellij.codeInsight.lookup.LookupElement
+import com.intellij.lang.parameterInfo.*
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.caches.resolve.getResolutionFacade
+import org.jetbrains.kotlin.idea.core.resolveCandidates
+import org.jetbrains.kotlin.idea.references.mainReference
+import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.psiUtil.allChildren
+import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
+import org.jetbrains.kotlin.psi.psiUtil.parents
+import org.jetbrains.kotlin.psi.psiUtil.startOffset
+import org.jetbrains.kotlin.renderer.DescriptorRenderer
+import org.jetbrains.kotlin.resolve.calls.callUtil.getCall
+import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
+import org.jetbrains.kotlin.types.Variance
+import org.jetbrains.kotlin.types.typeUtil.TypeNullability
+import org.jetbrains.kotlin.types.typeUtil.isAnyOrNullableAny
+import org.jetbrains.kotlin.types.typeUtil.nullability
+
+class KotlinClassTypeArgumentInfoHandler : KotlinTypeArgumentInfoHandlerBase<ClassDescriptor>() {
+    override fun fetchTypeParameters(descriptor: ClassDescriptor) = descriptor.typeConstructor.parameters
+
+    override fun findParameterOwners(argumentList: KtTypeArgumentList): Collection<ClassDescriptor>? {
+        val userType = argumentList.parent as? KtUserType ?: return null
+        val bindingContext = argumentList.analyze(BodyResolveMode.PARTIAL)
+        return userType.referenceExpression?.mainReference?.resolveToDescriptors(bindingContext)?.mapNotNull { it as? ClassDescriptor }
+    }
+
+    override fun getArgumentListAllowedParentClasses() = setOf(KtUserType::class.java)
+}
+
+class KotlinFunctionTypeArgumentInfoHandler : KotlinTypeArgumentInfoHandlerBase<FunctionDescriptor>() {
+    override fun fetchTypeParameters(descriptor: FunctionDescriptor) = descriptor.typeParameters
+
+    override fun findParameterOwners(argumentList: KtTypeArgumentList): Collection<FunctionDescriptor>? {
+        val callElement = argumentList.parent as? KtCallElement ?: return null
+        val bindingContext = argumentList.analyze(BodyResolveMode.PARTIAL)
+        val call = callElement.getCall(bindingContext) ?: return null
+        val candidates = call.resolveCandidates(bindingContext, callElement.getResolutionFacade())
+        return candidates
+                .map { it.resultingDescriptor }
+                .distinctBy { buildPresentation(it.typeParameters, -1).first }
+    }
+
+    override fun getArgumentListAllowedParentClasses() = setOf(KtCallElement::class.java)
+}
+
+abstract class KotlinTypeArgumentInfoHandlerBase<TParameterOwner : DeclarationDescriptor> : ParameterInfoHandlerWithTabActionSupport<KtTypeArgumentList, TParameterOwner, KtTypeProjection> {
+    protected abstract fun fetchTypeParameters(descriptor: TParameterOwner): List<TypeParameterDescriptor>
+    protected abstract fun findParameterOwners(argumentList: KtTypeArgumentList): Collection<TParameterOwner>?
+
+    override fun getActualParameterDelimiterType() = KtTokens.COMMA
+    override fun getActualParametersRBraceType() = KtTokens.GT
+
+    override fun getArgumentListClass() = KtTypeArgumentList::class.java
+
+    override fun getActualParameters(o: KtTypeArgumentList) = o.arguments.toTypedArray()
+
+    override fun getArgListStopSearchClasses() = setOf(KtNamedFunction::class.java, KtVariableDeclaration::class.java, KtClassOrObject::class.java)
+
+    override fun getParameterCloseChars() = ParameterInfoUtils.DEFAULT_PARAMETER_CLOSE_CHARS
+
+    override fun tracksParameterIndex() = true
+
+    override fun couldShowInLookup() = false
+    override fun getParametersForLookup(item: LookupElement?, context: ParameterInfoContext?) = emptyArray<Any>()
+    override fun getParametersForDocumentation(p: TParameterOwner, context: ParameterInfoContext?) = emptyArray<Any>()
+
+    override fun showParameterInfo(element: KtTypeArgumentList, context: CreateParameterInfoContext) {
+        context.showHint(element, element.textRange.startOffset, this)
+    }
+
+    override fun findElementForUpdatingParameterInfo(context: UpdateParameterInfoContext): KtTypeArgumentList? {
+        val element = context.file.findElementAt(context.offset) ?: return null
+        val argumentList = element.getParentOfType<KtTypeArgumentList>(true) ?: return null
+        val argument = element.parents.takeWhile { it != argumentList }.lastOrNull() as? KtTypeProjection
+        if (argument != null) {
+            val arguments = getActualParameters(argumentList)
+            val index = arguments.indexOf(element)
+            context.setCurrentParameter(index)
+            context.setHighlightedParameter(element)
+        }
+        return argumentList
+    }
+
+    override fun findElementForParameterInfo(context: CreateParameterInfoContext): KtTypeArgumentList? {
+        val file = context.file as? KtFile ?: return null
+
+        val token = file.findElementAt(context.offset) ?: return null
+        val argumentList = token.getParentOfType<KtTypeArgumentList>(true) ?: return null
+
+        val parameterOwners = findParameterOwners(argumentList) ?: return null
+
+        context.itemsToShow = parameterOwners.toTypedArray<Any>()
+        return argumentList
+    }
+
+    override fun updateParameterInfo(argumentList: KtTypeArgumentList, context: UpdateParameterInfoContext) {
+        if (context.parameterOwner !== argumentList) {
+            context.removeHint()
+        }
+
+        val offset = context.offset
+        val parameterIndex = argumentList.allChildren
+                .takeWhile { it.startOffset < offset }
+                .count { it.node.elementType == KtTokens.COMMA }
+        context.setCurrentParameter(parameterIndex)
+    }
+
+    override fun updateUI(itemToShow: TParameterOwner, context: ParameterInfoUIContext) {
+        if (!updateUIOrFail(itemToShow, context)) {
+            context.isUIComponentEnabled = false
+            return
+        }
+    }
+
+    private fun updateUIOrFail(itemToShow: TParameterOwner, context: ParameterInfoUIContext): Boolean {
+        val currentIndex = context.currentParameterIndex
+        if (currentIndex < 0) return false // by some strange reason we are invoked with currentParameterIndex == -1 during initialization
+
+        val parameters = fetchTypeParameters(itemToShow)
+
+        val (text, currentParameterStart, currentParameterEnd) = buildPresentation(parameters, currentIndex)
+
+        context.setupUIComponentPresentation(text, currentParameterStart, currentParameterEnd,
+                                             false/*isDisabled*/, false/*strikeout*/, false/*isDisabledBeforeHighlight*/,
+                                             context.defaultParameterColor)
+
+        return true
+    }
+
+    protected fun buildPresentation(
+            parameters: List<TypeParameterDescriptor>,
+            currentIndex: Int
+    ): Triple<String, Int, Int> {
+        var currentParameterStart = -1
+        var currentParameterEnd = -1
+
+        val text = buildString {
+            var needWhere = false
+            for ((index, parameter) in parameters.withIndex()) {
+                if (index > 0) append(", ")
+
+                if (index == currentIndex) {
+                    currentParameterStart = length
+                }
+
+                if (parameter.isReified) {
+                    append("reified ")
+                }
+
+                when (parameter.variance) {
+                    Variance.INVARIANT -> {}
+                    Variance.IN_VARIANCE -> append("in ")
+                    Variance.OUT_VARIANCE -> append("out ")
+                }
+
+                append(parameter.name.asString())
+
+                val upperBounds = parameter.upperBounds
+                if (upperBounds.size == 1) {
+                    val upperBound = upperBounds.single()
+                    if (!upperBound.isAnyOrNullableAny() || upperBound.nullability() == TypeNullability.NOT_NULL) { // skip Any? or Any!
+                        append(" : ").append(DescriptorRenderer.SHORT_NAMES_IN_TYPES.renderType(upperBound))
+                    }
+                }
+                else if (upperBounds.size > 1) {
+                    needWhere = true
+                }
+
+                if (index == currentIndex) {
+                    currentParameterEnd = length
+                }
+            }
+
+            if (needWhere) {
+                append(" where ")
+
+                var needComma = false
+                for (parameter in parameters) {
+                    val upperBounds = parameter.upperBounds
+                    if (upperBounds.size > 1) {
+                        for (upperBound in upperBounds) {
+                            if (needComma) append(", ")
+                            needComma = true
+                            append(parameter.name.asString()).append(" : ").append(DescriptorRenderer.SHORT_NAMES_IN_TYPES.renderType(upperBound))
+                        }
+                    }
+                }
+            }
+        }
+        return Triple(text, currentParameterStart, currentParameterEnd)
+    }
+}

idea/testData/parameterInfo/typeArguments/BaseClass.kt

@@ -0,0 +1,4 @@
+open class Base<out T, in V>
+
+class X : Base<<caret>>
+//Text: (<highlight>out T</highlight>, in V), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/Constraints.kt

@@ -0,0 +1,5 @@
+open class A<T1 : Any, T2, T3 : List<T1>> where T2 : Runnable, T2 : Cloneable, T3 : Runnable
+
+val v: A<X, <caret>>
+
+//Text: (T1 : Any, <highlight>T2</highlight>, T3 where T2 : Runnable, T2 : Cloneable, T3 : List<T1>, T3 : Runnable), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/ConstructorCall.kt

@@ -0,0 +1,5 @@
+open class Base<out T, in V>
+
+val v = Base<<caret>>
+
+//Text: (<highlight>out T</highlight>, in V), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/FunctionCall.kt

@@ -0,0 +1,7 @@
+fun <T, V> foo(t: T): T = t
+
+fun bar() {
+    foo<<caret>>()
+}
+
+//Text: (<highlight>T</highlight>, V), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/JavaClass.kt

@@ -0,0 +1,7 @@
+import java.util.*
+
+fun foo() {
+    ArrayList<<caret>>
+}
+
+//Text: (<highlight>E</highlight>), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/Overloads.kt

@@ -0,0 +1,12 @@
+fun <T, V> foo(t: T): T = t
+fun <T, V> foo(t: T, p: Int): T = t
+fun <X> foo(p: Boolean, x: X) {}
+
+fun bar() {
+    foo<<caret>>()
+}
+
+/*
+Text: (<highlight>T</highlight>, V), Disabled: false, Strikeout: false, Green: false
+Text: (<highlight>X</highlight>), Disabled: false, Strikeout: false, Green: false
+*/

idea/testData/parameterInfo/typeArguments/Reified.kt

@@ -0,0 +1,7 @@
+inline fun <reified T> foo(p: T) {}
+
+fun bar() {
+    foo<<caret>>
+}
+
+//Text: (<highlight>reified T</highlight>), Disabled: false, Strikeout: false, Green: false

idea/testData/parameterInfo/typeArguments/VariableType.kt

@@ -0,0 +1,5 @@
+open class A<T, V>
+
+val v: A<String, <caret>>
+
+//Text: (T, <highlight>V</highlight>), Disabled: false, Strikeout: false, Green: false

idea/tests/org/jetbrains/kotlin/idea/parameterInfo/AbstractParameterInfoTest.kt

@@ -22,7 +22,6 @@ import com.intellij.psi.PsiDocumentManager
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiWhiteSpace
 import com.intellij.testFramework.fixtures.LightCodeInsightFixtureTestCase
-import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.idea.KotlinLanguage
 import org.jetbrains.kotlin.idea.test.PluginTestCaseBase
 import org.jetbrains.kotlin.idea.test.ProjectDescriptorWithStdlibSources
@@ -77,8 +76,7 @@ abstract class AbstractParameterInfoTest : LightCodeInsightFixtureTestCase() {
         val parameterInfoUIContext = MockParameterInfoUIContext(parameterOwner, updateContext.currentParameter)
 
         for (item in mockCreateParameterInfoContext.itemsToShow) {
-            //noinspection unchecked
+            handler.updateUI(item, parameterInfoUIContext)
-            handler.updateUI(item as FunctionDescriptor, parameterInfoUIContext)
         }
         Assert.assertEquals(expectedResultText, parameterInfoUIContext.resultText)
     }

idea/tests/org/jetbrains/kotlin/idea/parameterInfo/ParameterInfoTestGenerated.java

@@ -304,4 +304,61 @@ public class ParameterInfoTestGenerated extends AbstractParameterInfoTest {
             doTest(fileName);
         }
     }
+
+    @TestMetadata("idea/testData/parameterInfo/typeArguments")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class TypeArguments extends AbstractParameterInfoTest {
+        public void testAllFilesPresentInTypeArguments() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/parameterInfo/typeArguments"), Pattern.compile("^(.+)\\.kt$"), true);
+        }
+
+        @TestMetadata("BaseClass.kt")
+        public void testBaseClass() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/BaseClass.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("Constraints.kt")
+        public void testConstraints() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/Constraints.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("ConstructorCall.kt")
+        public void testConstructorCall() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/ConstructorCall.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("FunctionCall.kt")
+        public void testFunctionCall() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/FunctionCall.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("JavaClass.kt")
+        public void testJavaClass() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/JavaClass.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("Overloads.kt")
+        public void testOverloads() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/Overloads.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("Reified.kt")
+        public void testReified() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/Reified.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("VariableType.kt")
+        public void testVariableType() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/parameterInfo/typeArguments/VariableType.kt");
+            doTest(fileName);
+        }
+    }
 }