Correct diagnostics and quick-fix for T::class with non-reified type parameter #KT-9590 fixed

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/checkers/ReifiedTypeParameterSubstitutionChecker.java

@@ -50,7 +50,7 @@ public class ReifiedTypeParameterSubstitutionChecker implements CallChecker {
 
             if (argumentDeclarationDescriptor instanceof TypeParameterDescriptor &&
                 !((TypeParameterDescriptor) argumentDeclarationDescriptor).isReified()) {
-                context.getTrace().report(Errors.TYPE_PARAMETER_AS_REIFIED.on(reportErrorOn, parameter));
+                context.getTrace().report(Errors.TYPE_PARAMETER_AS_REIFIED.on(reportErrorOn, (TypeParameterDescriptor) argumentDeclarationDescriptor));
             }
             else if (TypeUtilsKt.cannotBeReified(argument)) {
                 context.getTrace().report(Errors.REIFIED_TYPE_FORBIDDEN_SUBSTITUTION.on(reportErrorOn, argument));

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/DoubleColonExpressionResolver.kt

@@ -48,12 +48,11 @@ import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver
 import org.jetbrains.kotlin.resolve.scopes.receivers.Receiver
 import org.jetbrains.kotlin.resolve.scopes.receivers.TransientReceiver
 import org.jetbrains.kotlin.resolve.source.toSourceElement
-import org.jetbrains.kotlin.types.ErrorUtils
+import org.jetbrains.kotlin.types.*
-import org.jetbrains.kotlin.types.KotlinType
-import org.jetbrains.kotlin.types.KotlinTypeFactory
-import org.jetbrains.kotlin.types.TypeUtils
 import org.jetbrains.kotlin.types.TypeUtils.NO_EXPECTED_TYPE
 import org.jetbrains.kotlin.types.expressions.typeInfoFactory.createTypeInfo
+import org.jetbrains.kotlin.types.typeUtil.isTypeParameter
+import java.lang.UnsupportedOperationException
 import javax.inject.Inject
 
 sealed class DoubleColonLHS(val type: KotlinType) {
@@ -119,7 +118,12 @@ class DoubleColonExpressionResolver(
             reportError = !isAllowedInClassLiteral(type)
         }
 
-        if (type.isMarkedNullable || reportError) {
+
+        val typeParameterDescriptor = TypeUtils.getTypeParameterDescriptorOrNull(type)
+        if (type is SimpleType && !type.isMarkedNullable && typeParameterDescriptor != null && !typeParameterDescriptor.isReified) {
+            c.trace.report(TYPE_PARAMETER_AS_REIFIED.on(expression, typeParameterDescriptor))
+        }
+        else if (type.isMarkedNullable || reportError) {
             c.trace.report(CLASS_LITERAL_LHS_NOT_A_CLASS.on(expression))
         }
     }

compiler/testData/diagnostics/tests/classLiteral/nonClassesOnLHS.kt

@@ -9,7 +9,7 @@ val l1 = <!CLASS_LITERAL_LHS_NOT_A_CLASS!>List<String>?::class<!>
 val l2 = <!CLASS_LITERAL_LHS_NOT_A_CLASS!>List?::class<!>
 
 fun <T : Any> foo() {
-    val t1 = <!CLASS_LITERAL_LHS_NOT_A_CLASS!>T::class<!>
+    val t1 = <!TYPE_PARAMETER_AS_REIFIED!>T::class<!>
     val t2 = <!CLASS_LITERAL_LHS_NOT_A_CLASS!>T?::class<!>
 }
 

compiler/testData/diagnostics/tests/generics/tpAsReified/ClassDereference.kt

@@ -0,0 +1,3 @@
+
+fun <T: Any> dereferenceClass(): Any =
+        <!TYPE_PARAMETER_AS_REIFIED!>T::class<!>

compiler/testData/diagnostics/tests/generics/tpAsReified/ClassDereference.txt

@@ -0,0 +1,3 @@
+package
+
+public fun </*0*/ T : kotlin.Any> dereferenceClass(): kotlin.Any

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -8339,6 +8339,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                     doTest(fileName);
                 }
 
+                @TestMetadata("ClassDereference.kt")
+                public void testClassDereference() throws Exception {
+                    String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/generics/tpAsReified/ClassDereference.kt");
+                    doTest(fileName);
+                }
+
                 @TestMetadata("Conventions.kt")
                 public void testConventions() throws Exception {
                     String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/generics/tpAsReified/Conventions.kt");

idea/src/org/jetbrains/kotlin/idea/quickfix/AddReifiedToTypeParameterOfFunctionFix.kt

@@ -0,0 +1,68 @@
+/*
+ * 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.
+ */
+
+/*
+ * 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.quickfix
+
+import com.intellij.codeInsight.intention.IntentionAction
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.psi.KtFile
+import org.jetbrains.kotlin.psi.KtNamedFunction
+import org.jetbrains.kotlin.psi.KtTypeParameter
+import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
+
+class AddReifiedToTypeParameterOfFunctionFix(
+        typeParameter: KtTypeParameter,
+        val function: KtNamedFunction
+) : AddModifierFix(typeParameter, KtTokens.REIFIED_KEYWORD) {
+
+    val inlineFix = AddInlineToFunctionWithReifiedFix(function)
+
+    override fun getText() = "Make ${getElementName(element)} reified and ${getElementName(function)} inline"
+
+    override fun invoke(project: Project, editor: Editor?, file: KtFile) {
+        super.invoke(project, editor, file)
+        inlineFix.invoke(project, editor, file)
+    }
+
+    companion object Factory : KotlinSingleIntentionActionFactory() {
+        override fun createAction(diagnostic: Diagnostic): IntentionAction? {
+            val element = Errors.TYPE_PARAMETER_AS_REIFIED.cast(diagnostic)
+            val function = element.psiElement.getStrictParentOfType<KtNamedFunction>()
+            val parameter = function?.typeParameterList?.parameters?.get(element.a.index) ?: return null
+            return AddReifiedToTypeParameterOfFunctionFix(parameter, function)
+        }
+    }
+}

idea/src/org/jetbrains/kotlin/idea/quickfix/QuickFixRegistrar.kt

@@ -418,5 +418,7 @@ class QuickFixRegistrar : QuickFixContributor {
         UNRESOLVED_REFERENCE.registerFactory(CreateTypeParameterByRefActionFactory)
 
         FINAL_UPPER_BOUND.registerFactory(InlineTypeParameterFix)
+
+        TYPE_PARAMETER_AS_REIFIED.registerFactory(AddReifiedToTypeParameterOfFunctionFix)
     }
 }

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/doubleColonClass.kt

@@ -0,0 +1,4 @@
+// "Make 'T' reified and 'dereferenceClass' inline" "true"
+
+fun <T: Any> dereferenceClass(): Any =
+        T::class<caret>

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/doubleColonClass.kt.after

@@ -0,0 +1,4 @@
+// "Make 'T' reified and 'dereferenceClass' inline" "true"
+
+inline fun <reified T: Any> dereferenceClass(): Any =
+        T::class<caret>

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/secondTypeParameter.kt

@@ -0,0 +1,6 @@
+// "Make 'R' reified and 'flatten' inline" "true"
+// WITH_RUNTIME
+
+fun <T: Iterable<Array<R>>, R> T.flatten(): Array<R> {
+    return this.flatMap { it.asIterable() }.toTypedArray<caret>()
+}

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/secondTypeParameter.kt.after

@@ -0,0 +1,6 @@
+// "Make 'R' reified and 'flatten' inline" "true"
+// WITH_RUNTIME
+
+inline fun <T: Iterable<Array<R>>, reified R> T.flatten(): Array<R> {
+    return this.flatMap { it.asIterable() }.toTypedArray<caret>()
+}

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/toTypedArray.kt

@@ -0,0 +1,6 @@
+// "Make 'T' reified and 'flatten' inline" "true"
+// WITH_RUNTIME
+
+fun <T> Array<Array<T>>.flatten(): Array<T> {
+    return this.flatMap { it.asIterable() }.toTypedArray<caret>()
+}

idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/toTypedArray.kt.after

@@ -0,0 +1,6 @@
+// "Make 'T' reified and 'flatten' inline" "true"
+// WITH_RUNTIME
+
+inline fun <reified T> Array<Array<T>>.flatten(): Array<T> {
+    return this.flatMap { it.asIterable() }.toTypedArray<caret>()
+}

idea/tests/org/jetbrains/kotlin/idea/quickfix/QuickFixTestGenerated.java

@@ -413,6 +413,33 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
         }
     }
 
+    @TestMetadata("idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class AddReifiedToTypeParameterOfFunctionFix extends AbstractQuickFixTest {
+        public void testAllFilesPresentInAddReifiedToTypeParameterOfFunctionFix() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), true);
+        }
+
+        @TestMetadata("doubleColonClass.kt")
+        public void testDoubleColonClass() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/doubleColonClass.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("secondTypeParameter.kt")
+        public void testSecondTypeParameter() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/secondTypeParameter.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("toTypedArray.kt")
+        public void testToTypedArray() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/quickfix/addReifiedToTypeParameterOfFunctionFix/toTypedArray.kt");
+            doTest(fileName);
+        }
+    }
+
     @TestMetadata("idea/testData/quickfix/addRunBeforeLambda")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)