Prohibit type parameters for local variables in LV >= 1.4 & -progressive

#KT-8341 Fixed

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -954,6 +954,8 @@ public interface Errors {
     DiagnosticFactory0<KtTypeReference> LOCAL_EXTENSION_PROPERTY = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtPropertyAccessor> LOCAL_VARIABLE_WITH_GETTER = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtPropertyAccessor> LOCAL_VARIABLE_WITH_SETTER = DiagnosticFactory0.create(ERROR);
+    DiagnosticFactory0<KtTypeParameterList> LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING = DiagnosticFactory0.create(WARNING);
+    DiagnosticFactory0<KtTypeParameterList> LOCAL_VARIABLE_WITH_TYPE_PARAMETERS = DiagnosticFactory0.create(ERROR);
 
     DiagnosticFactory3<KtExpression, DeclarationDescriptor, Visibility, DeclarationDescriptor> INVISIBLE_SETTER = DiagnosticFactory3.create(ERROR);
 

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -399,6 +399,8 @@ public class DefaultErrorMessages {
         MAP.put(LOCAL_EXTENSION_PROPERTY, "Local extension properties are not allowed");
         MAP.put(LOCAL_VARIABLE_WITH_GETTER, "Local variables are not allowed to have getters");
         MAP.put(LOCAL_VARIABLE_WITH_SETTER, "Local variables are not allowed to have setters");
+        MAP.put(LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING, "Type parameters for local variables are deprecated");
+        MAP.put(LOCAL_VARIABLE_WITH_TYPE_PARAMETERS, "Local variables are not allowed to have type parameters");
         MAP.put(VAL_WITH_SETTER, "A 'val'-property cannot have a setter");
 
         MAP.put(DEPRECATED_IDENTITY_EQUALS, "Identity equality for arguments of types {0} and {1} is deprecated", RENDER_TYPE, RENDER_TYPE);

compiler/frontend/src/org/jetbrains/kotlin/resolve/PlatformConfiguratorBase.kt

@@ -33,7 +33,8 @@ private val DEFAULT_DECLARATION_CHECKERS = listOf(
     PropertiesWithBackingFieldsInsideInlineClass(),
     AnnotationClassTargetAndRetentionChecker(),
     ReservedMembersAndConstructsForInlineClass(),
-    ResultClassInReturnTypeChecker()
+    ResultClassInReturnTypeChecker(),
+    LocalVariableTypeParametersChecker()
 )
 
 private val DEFAULT_CALL_CHECKERS = listOf(

compiler/frontend/src/org/jetbrains/kotlin/resolve/checkers/LocalVariableTypeParametersChecker.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.resolve.checkers
+
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.psi.KtProperty
+
+class LocalVariableTypeParametersChecker : DeclarationChecker {
+    override fun check(declaration: KtDeclaration, descriptor: DeclarationDescriptor, context: DeclarationCheckerContext) {
+        if (declaration !is KtProperty || descriptor !is LocalVariableDescriptor) return
+
+        val typeParameters = declaration.typeParameters
+        val typeParametersList = declaration.typeParameterList
+        if (typeParameters.isEmpty() || typeParametersList == null) return
+
+        val diagnostic =
+            if (context.languageVersionSettings.supportsFeature(LanguageFeature.ProhibitTypeParametersForLocalVariables))
+                Errors.LOCAL_VARIABLE_WITH_TYPE_PARAMETERS
+            else
+                Errors.LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING
+
+        context.trace.report(diagnostic.on(typeParametersList))
+    }
+}

compiler/testData/diagnostics/tests/annotations/AnnotationsForPropertyTypeParameter.kt

@@ -7,6 +7,6 @@ class SomeClass {
     val <<!WRONG_ANNOTATION_TARGET!>@A1<!> <!WRONG_ANNOTATION_TARGET!>@A2(3)<!> <!WRONG_ANNOTATION_TARGET, REPEATED_ANNOTATION!>@A2<!> <!WRONG_ANNOTATION_TARGET, REPEATED_ANNOTATION!>@A1(<!TOO_MANY_ARGUMENTS!>12<!>)<!> <!WRONG_ANNOTATION_TARGET, REPEATED_ANNOTATION!>@A2(<!TYPE_MISMATCH!>"Test"<!>)<!> T> T.field: Int get() = 12
 
     fun foo() {
-        val <<!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A1<!><!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!>(3)<!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!><!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A1<!>(12)<!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!>("Test")<!> T> <!UNUSED_VARIABLE!>localVal<!> = 12
+        val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><<!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A1<!><!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!>(3)<!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!><!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A1<!>(12)<!> <!WRONG_ANNOTATION_TARGET!>@<!DEBUG_INFO_MISSING_UNRESOLVED!>A2<!>("Test")<!> T><!> <!UNUSED_VARIABLE!>localVal<!> = 12
     }
 }

compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_3.kt

@@ -0,0 +1,19 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+// !LANGUAGE: -ProhibitTypeParametersForLocalVariables
+
+import kotlin.reflect.KProperty
+
+fun test() {
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T><!> a0 = 0
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T : <!DEBUG_INFO_MISSING_UNRESOLVED!>__UNRESOLVED__<!>><!> a1 = ""
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T : <!DEBUG_INFO_MISSING_UNRESOLVED!>String<!>><!> a2 = 0
+    <!WRONG_MODIFIER_TARGET!>const<!> val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T><!> a3 = 0
+    <!INAPPLICABLE_LATEINIT_MODIFIER, INAPPLICABLE_LATEINIT_MODIFIER, INAPPLICABLE_LATEINIT_MODIFIER!>lateinit<!> val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T><!> a4 = 0
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T><!> a5 by Delegate<Int>()
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING!><T><!> a6 by Delegate<<!UNRESOLVED_REFERENCE!>T<!>>()
+}
+
+class Delegate<F> {
+    operator fun getValue(thisRef: Any?, property: KProperty<*>): String = ""
+    operator fun setValue(thisRef: Any?, property: KProperty<*>, value: String) {}
+}

compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_3.txt

@@ -0,0 +1,12 @@
+package
+
+public fun test(): kotlin.Unit
+
+public final class Delegate</*0*/ F> {
+    public constructor Delegate</*0*/ F>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ property: kotlin.reflect.KProperty<*>): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ property: kotlin.reflect.KProperty<*>, /*2*/ value: kotlin.String): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_4.kt

@@ -0,0 +1,19 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+// !LANGUAGE: +ProhibitTypeParametersForLocalVariables
+
+import kotlin.reflect.KProperty
+
+fun test() {
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T><!> a0 = 0
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T : <!DEBUG_INFO_MISSING_UNRESOLVED!>__UNRESOLVED__<!>><!> a1 = ""
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T : <!DEBUG_INFO_MISSING_UNRESOLVED!>String<!>><!> a2 = 0
+    <!WRONG_MODIFIER_TARGET!>const<!> val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T><!> a3 = 0
+    <!INAPPLICABLE_LATEINIT_MODIFIER, INAPPLICABLE_LATEINIT_MODIFIER, INAPPLICABLE_LATEINIT_MODIFIER!>lateinit<!> val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T><!> a4 = 0
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T><!> a5 by Delegate<Int>()
+    val <!LOCAL_VARIABLE_WITH_TYPE_PARAMETERS!><T><!> a6 by Delegate<<!UNRESOLVED_REFERENCE!>T<!>>()
+}
+
+class Delegate<F> {
+    operator fun getValue(thisRef: Any?, property: KProperty<*>): String = ""
+    operator fun setValue(thisRef: Any?, property: KProperty<*>, value: String) {}
+}

compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_4.txt

@@ -0,0 +1,12 @@
+package
+
+public fun test(): kotlin.Unit
+
+public final class Delegate</*0*/ F> {
+    public constructor Delegate</*0*/ F>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ property: kotlin.reflect.KProperty<*>): kotlin.String
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ property: kotlin.reflect.KProperty<*>, /*2*/ value: kotlin.String): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

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

@@ -5133,6 +5133,16 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 runTest("compiler/testData/diagnostics/tests/declarationChecks/LocalVariableWithNoTypeInformation.kt");
             }
 
+            @TestMetadata("localVariablesWithTypeParameters_1_3.kt")
+            public void testLocalVariablesWithTypeParameters_1_3() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_3.kt");
+            }
+
+            @TestMetadata("localVariablesWithTypeParameters_1_4.kt")
+            public void testLocalVariablesWithTypeParameters_1_4() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_4.kt");
+            }
+
             @TestMetadata("mulitpleVarargParameters.kt")
             public void testMulitpleVarargParameters() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/declarationChecks/mulitpleVarargParameters.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java

@@ -5133,6 +5133,16 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 runTest("compiler/testData/diagnostics/tests/declarationChecks/LocalVariableWithNoTypeInformation.kt");
             }
 
+            @TestMetadata("localVariablesWithTypeParameters_1_3.kt")
+            public void testLocalVariablesWithTypeParameters_1_3() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_3.kt");
+            }
+
+            @TestMetadata("localVariablesWithTypeParameters_1_4.kt")
+            public void testLocalVariablesWithTypeParameters_1_4() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/declarationChecks/localVariablesWithTypeParameters_1_4.kt");
+            }
+
             @TestMetadata("mulitpleVarargParameters.kt")
             public void testMulitpleVarargParameters() throws Exception {
                 runTest("compiler/testData/diagnostics/tests/declarationChecks/mulitpleVarargParameters.kt");

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -94,6 +94,7 @@ enum class LanguageFeature(
     WarningOnMainUnusedParameter(KOTLIN_1_4),
     PolymorphicSignature(KOTLIN_1_4),
     ProhibitConcurrentHashMapContains(KOTLIN_1_4, kind = BUG_FIX),
+    ProhibitTypeParametersForLocalVariables(KOTLIN_1_4, kind = BUG_FIX),
 
     ProperVisibilityForCompanionObjectInstanceField(sinceVersion = null, kind = BUG_FIX),
     // Temporarily disabled, see KT-27084/KT-22379

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

@@ -271,6 +271,9 @@ class QuickFixRegistrar : QuickFixContributor {
 
         TYPE_ARGUMENTS_REDUNDANT_IN_SUPER_QUALIFIER.registerFactory(RemovePsiElementSimpleFix.RemoveTypeArgumentsFactory)
 
+        LOCAL_VARIABLE_WITH_TYPE_PARAMETERS.registerFactory(RemovePsiElementSimpleFix.RemoveTypeParametersFactory)
+        LOCAL_VARIABLE_WITH_TYPE_PARAMETERS_WARNING.registerFactory(RemovePsiElementSimpleFix.RemoveTypeParametersFactory)
+
         UNCHECKED_CAST.registerFactory(ChangeToStarProjectionFix)
         CANNOT_CHECK_FOR_ERASED.registerFactory(ChangeToStarProjectionFix)
 

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

@@ -58,6 +58,13 @@ open class RemovePsiElementSimpleFix(element: PsiElement, private val text: Stri
         }
     }
 
+    object RemoveTypeParametersFactory : KotlinSingleIntentionActionFactory() {
+        public override fun createAction(diagnostic: Diagnostic): KotlinQuickFixAction<PsiElement>? {
+            val element = diagnostic.psiElement.getNonStrictParentOfType<KtTypeParameterList>() ?: return null
+            return RemovePsiElementSimpleFix(element, "Remove type parameters")
+        }
+    }
+
     object RemoveVariableFactory : KotlinSingleIntentionActionFactory() {
         public override fun createAction(diagnostic: Diagnostic): KotlinQuickFixAction<PsiElement>? {
             val expression = diagnostic.psiElement.getNonStrictParentOfType<KtProperty>() ?: return null

idea/testData/quickfix/localVariableWithTypeParameters/removeTypeParametersFromLocalVariable.kt

@@ -0,0 +1,5 @@
+// "Remove type parameters" "true"
+
+fun test() {
+    val <caret><T : unresovled_reference, K> x = 0
+}

idea/testData/quickfix/localVariableWithTypeParameters/removeTypeParametersFromLocalVariable.kt.after

@@ -0,0 +1,5 @@
+// "Remove type parameters" "true"
+
+fun test() {
+    val x = 0
+}

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

@@ -2840,6 +2840,19 @@ public class QuickFixMultiFileTestGenerated extends AbstractQuickFixMultiFileTes
         }
     }
 
+    @TestMetadata("idea/testData/quickfix/localVariableWithTypeParameters")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class LocalVariableWithTypeParameters extends AbstractQuickFixMultiFileTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doTestWithExtraFile, TargetBackend.ANY, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInLocalVariableWithTypeParameters() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/localVariableWithTypeParameters"), Pattern.compile("^(\\w+)\\.((before\\.Main\\.\\w+)|(test))$"), TargetBackend.ANY, true);
+        }
+    }
+
     @TestMetadata("idea/testData/quickfix/makeConstructorParameterProperty")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)

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

@@ -7415,6 +7415,24 @@ public class QuickFixTestGenerated extends AbstractQuickFixTest {
         }
     }
 
+    @TestMetadata("idea/testData/quickfix/localVariableWithTypeParameters")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class LocalVariableWithTypeParameters extends AbstractQuickFixTest {
+        private void runTest(String testDataFilePath) throws Exception {
+            KotlinTestUtils.runTest(this::doTest, TargetBackend.ANY, testDataFilePath);
+        }
+
+        public void testAllFilesPresentInLocalVariableWithTypeParameters() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/quickfix/localVariableWithTypeParameters"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), TargetBackend.ANY, true);
+        }
+
+        @TestMetadata("removeTypeParametersFromLocalVariable.kt")
+        public void testRemoveTypeParametersFromLocalVariable() throws Exception {
+            runTest("idea/testData/quickfix/localVariableWithTypeParameters/removeTypeParametersFromLocalVariable.kt");
+        }
+    }
+
     @TestMetadata("idea/testData/quickfix/makeConstructorParameterProperty")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)