KT-35811: Type parameter angle brackets followed by equal sign are parsed incorrectly if whitespace is missing

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosisCompilerTestFE10TestdataTestGenerated.java

@@ -10655,6 +10655,28 @@ public class DiagnosisCompilerTestFE10TestdataTestGenerated extends AbstractDiag
             }
         }
 
+        @Nested
+        @TestMetadata("compiler/testData/diagnostics/tests/expressionAfterTypeReference")
+        @TestDataPath("$PROJECT_ROOT")
+        public class ExpressionAfterTypeReference {
+            @Test
+            public void testAllFilesPresentInExpressionAfterTypeReference() throws Exception {
+                KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/expressionAfterTypeReference"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.fir\\.kts?$"), true);
+            }
+
+            @Test
+            @TestMetadata("allowExpressionAfterTypeReference.kt")
+            public void testAllowExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.kt");
+            }
+
+            @Test
+            @TestMetadata("forbidExpressionAfterTypeReference.kt")
+            public void testForbidExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.kt");
+            }
+        }
+
         @Nested
         @TestMetadata("compiler/testData/diagnostics/tests/extensions")
         @TestDataPath("$PROJECT_ROOT")

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java

@@ -10655,6 +10655,28 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
             }
         }
 
+        @Nested
+        @TestMetadata("compiler/testData/diagnostics/tests/expressionAfterTypeReference")
+        @TestDataPath("$PROJECT_ROOT")
+        public class ExpressionAfterTypeReference {
+            @Test
+            public void testAllFilesPresentInExpressionAfterTypeReference() throws Exception {
+                KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/expressionAfterTypeReference"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.fir\\.kts?$"), true);
+            }
+
+            @Test
+            @TestMetadata("allowExpressionAfterTypeReference.kt")
+            public void testAllowExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.kt");
+            }
+
+            @Test
+            @TestMetadata("forbidExpressionAfterTypeReference.kt")
+            public void testForbidExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.kt");
+            }
+        }
+
         @Nested
         @TestMetadata("compiler/testData/diagnostics/tests/extensions")
         @TestDataPath("$PROJECT_ROOT")

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsWithLightTreeTestGenerated.java

@@ -10655,6 +10655,28 @@ public class FirOldFrontendDiagnosticsWithLightTreeTestGenerated extends Abstrac
             }
         }
 
+        @Nested
+        @TestMetadata("compiler/testData/diagnostics/tests/expressionAfterTypeReference")
+        @TestDataPath("$PROJECT_ROOT")
+        public class ExpressionAfterTypeReference {
+            @Test
+            public void testAllFilesPresentInExpressionAfterTypeReference() throws Exception {
+                KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/expressionAfterTypeReference"), Pattern.compile("^(.+)\\.kt$"), Pattern.compile("^(.+)\\.fir\\.kts?$"), true);
+            }
+
+            @Test
+            @TestMetadata("allowExpressionAfterTypeReference.kt")
+            public void testAllowExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.kt");
+            }
+
+            @Test
+            @TestMetadata("forbidExpressionAfterTypeReference.kt")
+            public void testForbidExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.kt");
+            }
+        }
+
         @Nested
         @TestMetadata("compiler/testData/diagnostics/tests/extensions")
         @TestDataPath("$PROJECT_ROOT")

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

@@ -235,6 +235,8 @@ public interface Errors {
 
     DiagnosticFactoryForDeprecation1<PsiElement, CallableDescriptor> PROGRESSIONS_CHANGING_RESOLVE = DiagnosticFactoryForDeprecation1.create(LanguageFeature.ProgressionsChangingResolve);
 
+    DiagnosticFactory0<PsiElement> EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED = DiagnosticFactory0.create(ERROR);
+
     ////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
     // Errors in declarations

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

@@ -625,6 +625,7 @@ public class DefaultErrorMessages {
                                                "This call will resolve to another declaration: {0}. " +
                                                "See https://youtrack.jetbrains.com/issue/KT-49276 for more details. " +
                                                "Please specify a progression type of argument explicitly through explicit cast to resolve to a proper declaration", COMPACT);
+        MAP.put(EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED, "Expression body directly after type without a whitespace in-between the '>=' is only allowed since version 1.8");
 
         MAP.put(TOO_MANY_ARGUMENTS, "Too many arguments for {0}", FQ_NAMES_IN_TYPES);
 

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

@@ -51,6 +51,7 @@ private val DEFAULT_DECLARATION_CHECKERS = listOf(
     SubtypingBetweenContextReceiversChecker,
     ValueParameterUsageInDefaultArgumentChecker,
     CyclicAnnotationsChecker,
+    ExpressionAfterTypeParameterWithoutSpacingChecker,
 )
 
 private val DEFAULT_CALL_CHECKERS = listOf(

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

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * 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 com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyGetterDescriptor
+import org.jetbrains.kotlin.descriptors.PropertySetterDescriptor
+import org.jetbrains.kotlin.diagnostics.Errors
+import org.jetbrains.kotlin.lexer.KtTokens
+import org.jetbrains.kotlin.psi.*
+
+object ExpressionAfterTypeParameterWithoutSpacingChecker : DeclarationChecker {
+
+    override fun check(declaration: KtDeclaration, descriptor: DeclarationDescriptor, context: DeclarationCheckerContext) {
+        if (context.languageVersionSettings.supportsFeature(LanguageFeature.AllowExpressionAfterTypeReferenceWithoutSpacing)) return
+        when (declaration) {
+            is KtProperty -> {
+                if (descriptor is PropertyGetterDescriptor || descriptor is PropertySetterDescriptor) return
+                check(declaration.typeReference, declaration.initializer, context)
+            }
+            is KtFunction -> {
+                for (valueParameter in declaration.valueParameters) {
+                    check(valueParameter.typeReference, valueParameter.defaultValue, context)
+                }
+
+                check(declaration.typeReference, declaration.bodyExpression, context)
+            }
+        }
+    }
+
+    private fun check(typeReference: KtTypeReference?, expression: KtExpression?, context: DeclarationCheckerContext) {
+        if (typeReference == null) return
+        if (expression == null) return
+
+        val leftSide = typeReference.getRightMostToken()
+        if (leftSide.node.elementType != KtTokens.GT) return
+
+        val rightSide = typeReference.nextSibling?.getLeftMostToken() ?: return
+        if (rightSide.node.elementType != KtTokens.EQ) return
+
+        context.trace.report(Errors.EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED.on(rightSide))
+    }
+
+    private fun PsiElement.getLeftMostToken(): PsiElement {
+        var current = firstChild ?: return this
+        while (true) {
+            current = current.firstChild ?: return current
+        }
+    }
+
+    private fun PsiElement.getRightMostToken(): PsiElement {
+        var current = lastChild ?: return this
+        while (true) {
+            current = current.lastChild ?: return current
+        }
+    }
+}

compiler/psi/src/org/jetbrains/kotlin/lexer/Kotlin.flex

@@ -283,7 +283,6 @@ LONELY_BACKTICK=`
 "++"         { return KtTokens.PLUSPLUS  ; }
 "--"         { return KtTokens.MINUSMINUS; }
 "<="         { return KtTokens.LTEQ      ; }
-">="         { return KtTokens.GTEQ      ; }
 "=="         { return KtTokens.EQEQ      ; }
 "!="         { return KtTokens.EXCLEQ    ; }
 "&&"         { return KtTokens.ANDAND    ; }

compiler/psi/src/org/jetbrains/kotlin/parsing/KotlinParsing.java

@@ -2428,11 +2428,13 @@ public class KotlinParsing extends AbstractKotlinParsing {
             projection.done(TYPE_PROJECTION);
             if (!at(COMMA)) break;
             advance(); // COMMA
-            if (at(GT)) {
+            if (at(GT) || at(GTEQ)) {
                 break;
             }
         }
 
+        myBuilder.disableJoiningComplexTokens();
+
         boolean atGT = at(GT);
         if (!atGT) {
             error("Expecting a '>'");
@@ -2440,6 +2442,9 @@ public class KotlinParsing extends AbstractKotlinParsing {
         else {
             advance(); // GT
         }
+
+        myBuilder.restoreJoiningComplexTokensState();
+
         myBuilder.restoreNewlinesState();
         return atGT;
     }

compiler/psi/src/org/jetbrains/kotlin/parsing/SemanticWhitespaceAwarePsiBuilderImpl.java

@@ -30,7 +30,7 @@ import org.jetbrains.kotlin.lexer.KtTokens;
 import static org.jetbrains.kotlin.lexer.KtTokens.*;
 
 public class SemanticWhitespaceAwarePsiBuilderImpl extends PsiBuilderAdapter implements SemanticWhitespaceAwarePsiBuilder {
-    private final TokenSet complexTokens = TokenSet.create(SAFE_ACCESS, ELVIS, EXCLEXCL);
+    private final TokenSet complexTokens = TokenSet.create(SAFE_ACCESS, ELVIS, EXCLEXCL, GTEQ);
     private final Stack<Boolean> joinComplexTokens = new Stack<>();
 
     private final Stack<Boolean> newlinesEnabled = new Stack<>();
@@ -155,6 +155,10 @@ public class SemanticWhitespaceAwarePsiBuilderImpl extends PsiBuilderAdapter imp
             IElementType nextRawToken = rawLookup(rawLookupSteps);
             if (nextRawToken == EXCL) return EXCLEXCL;
         }
+        else if (rawTokenType == GT){
+            IElementType nextRawToken = rawLookup(rawLookupSteps);
+            if (nextRawToken == EQ) return GTEQ;
+        }
         return rawTokenType;
     }
 
@@ -181,9 +185,11 @@ public class SemanticWhitespaceAwarePsiBuilderImpl extends PsiBuilderAdapter imp
         if (!joinComplexTokens()) return super.getTokenText();
         IElementType tokenType = getTokenType();
         if (complexTokens.contains(tokenType)) {
-                if (tokenType == ELVIS) return "?:";
-                if (tokenType == SAFE_ACCESS) return "?.";
-            }
+            if (tokenType == ELVIS) return "?:";
+            if (tokenType == SAFE_ACCESS) return "?.";
+            if (tokenType == EXCLEXCL) return "!!";
+            if (tokenType == GTEQ) return ">=";
+        }
         return super.getTokenText();
     }
 

compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.kt

@@ -0,0 +1,14 @@
+// FIR_IDENTICAL
+// !LANGUAGE: +AllowExpressionAfterTypeReferenceWithoutSpacing
+// ISSUE: KT-35811
+
+class A<T>
+
+val reportedProperty: A<String>=A()
+fun reportedFunction(a: A<String>=A()): A<String>=a
+
+val unreportedProperty0: A<String> =A()
+fun unreportedFunction0(a: A<String> =A()): A<String> =A()
+
+val unreportedProperty1: String=""
+fun unreportedFunction1(a: Int=0): Int=a

compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.txt

@@ -0,0 +1,15 @@
+package
+
+public val reportedProperty: A<kotlin.String>
+public val unreportedProperty0: A<kotlin.String>
+public val unreportedProperty1: kotlin.String = ""
+public fun reportedFunction(/*0*/ a: A<kotlin.String> = ...): A<kotlin.String>
+public fun unreportedFunction0(/*0*/ a: A<kotlin.String> = ...): A<kotlin.String>
+public fun unreportedFunction1(/*0*/ a: kotlin.Int = ...): kotlin.Int
+
+public final class A</*0*/ T> {
+    public constructor A</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.fir.kt

@@ -0,0 +1,13 @@
+// !LANGUAGE: -AllowExpressionAfterTypeReferenceWithoutSpacing
+// ISSUE: KT-35811
+
+class A<T>
+
+val reportedProperty: A<String>=A()
+fun reportedFunction(a: A<String>=A()): A<String>=a
+
+val unreportedProperty0: A<String> =A()
+fun unreportedFunction0(a: A<String> =A()): A<String> =A()
+
+val unreportedProperty1: String=""
+fun unreportedFunction1(a: Int=0): Int=a

compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.kt

@@ -0,0 +1,13 @@
+// !LANGUAGE: -AllowExpressionAfterTypeReferenceWithoutSpacing
+// ISSUE: KT-35811
+
+class A<T>
+
+val reportedProperty: A<String><!EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED!>=<!>A()
+fun reportedFunction(a: A<String><!EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED!>=<!>A()): A<String><!EXPRESSION_AFTER_TYPE_REFERENCE_WITHOUT_SPACING_NOT_ALLOWED!>=<!>a
+
+val unreportedProperty0: A<String> =A()
+fun unreportedFunction0(a: A<String> =A()): A<String> =A()
+
+val unreportedProperty1: String=""
+fun unreportedFunction1(a: Int=0): Int=a

compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.txt

@@ -0,0 +1,15 @@
+package
+
+public val reportedProperty: A<kotlin.String>
+public val unreportedProperty0: A<kotlin.String>
+public val unreportedProperty1: kotlin.String = ""
+public fun reportedFunction(/*0*/ a: A<kotlin.String> = ...): A<kotlin.String>
+public fun unreportedFunction0(/*0*/ a: A<kotlin.String> = ...): A<kotlin.String>
+public fun unreportedFunction1(/*0*/ a: kotlin.Int = ...): kotlin.Int
+
+public final class A</*0*/ T> {
+    public constructor A</*0*/ T>()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/psi/recovery/TypeParameterBeforeEqualSign.kt

@@ -0,0 +1,3 @@
+val a: A<B>= 1
+fun a(): A<B>= 1
+fun a(a: A<B>= 1) {}

compiler/testData/psi/recovery/TypeParameterBeforeEqualSign.txt

@@ -0,0 +1,85 @@
+KtFile: TypeParameterBeforeEqualSign.kt
+  PACKAGE_DIRECTIVE
+    <empty list>
+  IMPORT_LIST
+    <empty list>
+  PROPERTY
+    PsiElement(val)('val')
+    PsiWhiteSpace(' ')
+    PsiElement(IDENTIFIER)('a')
+    PsiElement(COLON)(':')
+    PsiWhiteSpace(' ')
+    TYPE_REFERENCE
+      USER_TYPE
+        REFERENCE_EXPRESSION
+          PsiElement(IDENTIFIER)('A')
+        TYPE_ARGUMENT_LIST
+          PsiElement(LT)('<')
+          TYPE_PROJECTION
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION
+                  PsiElement(IDENTIFIER)('B')
+          PsiElement(GT)('>')
+    PsiElement(EQ)('=')
+    PsiWhiteSpace(' ')
+    INTEGER_CONSTANT
+      PsiElement(INTEGER_LITERAL)('1')
+  PsiWhiteSpace('\n')
+  FUN
+    PsiElement(fun)('fun')
+    PsiWhiteSpace(' ')
+    PsiElement(IDENTIFIER)('a')
+    VALUE_PARAMETER_LIST
+      PsiElement(LPAR)('(')
+      PsiElement(RPAR)(')')
+    PsiElement(COLON)(':')
+    PsiWhiteSpace(' ')
+    TYPE_REFERENCE
+      USER_TYPE
+        REFERENCE_EXPRESSION
+          PsiElement(IDENTIFIER)('A')
+        TYPE_ARGUMENT_LIST
+          PsiElement(LT)('<')
+          TYPE_PROJECTION
+            TYPE_REFERENCE
+              USER_TYPE
+                REFERENCE_EXPRESSION
+                  PsiElement(IDENTIFIER)('B')
+          PsiElement(GT)('>')
+    PsiElement(EQ)('=')
+    PsiWhiteSpace(' ')
+    INTEGER_CONSTANT
+      PsiElement(INTEGER_LITERAL)('1')
+  PsiWhiteSpace('\n')
+  FUN
+    PsiElement(fun)('fun')
+    PsiWhiteSpace(' ')
+    PsiElement(IDENTIFIER)('a')
+    VALUE_PARAMETER_LIST
+      PsiElement(LPAR)('(')
+      VALUE_PARAMETER
+        PsiElement(IDENTIFIER)('a')
+        PsiElement(COLON)(':')
+        PsiWhiteSpace(' ')
+        TYPE_REFERENCE
+          USER_TYPE
+            REFERENCE_EXPRESSION
+              PsiElement(IDENTIFIER)('A')
+            TYPE_ARGUMENT_LIST
+              PsiElement(LT)('<')
+              TYPE_PROJECTION
+                TYPE_REFERENCE
+                  USER_TYPE
+                    REFERENCE_EXPRESSION
+                      PsiElement(IDENTIFIER)('B')
+              PsiElement(GT)('>')
+        PsiElement(EQ)('=')
+        PsiWhiteSpace(' ')
+        INTEGER_CONSTANT
+          PsiElement(INTEGER_LITERAL)('1')
+      PsiElement(RPAR)(')')
+    PsiWhiteSpace(' ')
+    BLOCK
+      PsiElement(LBRACE)('{')
+      PsiElement(RBRACE)('}')

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -10661,6 +10661,28 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
             }
         }
 
+        @Nested
+        @TestMetadata("compiler/testData/diagnostics/tests/expressionAfterTypeReference")
+        @TestDataPath("$PROJECT_ROOT")
+        public class ExpressionAfterTypeReference {
+            @Test
+            public void testAllFilesPresentInExpressionAfterTypeReference() throws Exception {
+                KtTestUtil.assertAllTestsPresentByMetadataWithExcluded(this.getClass(), new File("compiler/testData/diagnostics/tests/expressionAfterTypeReference"), Pattern.compile("^(.*)\\.kts?$"), Pattern.compile("^(.+)\\.fir\\.kts?$"), true);
+            }
+
+            @Test
+            @TestMetadata("allowExpressionAfterTypeReference.kt")
+            public void testAllowExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/allowExpressionAfterTypeReference.kt");
+            }
+
+            @Test
+            @TestMetadata("forbidExpressionAfterTypeReference.kt")
+            public void testForbidExpressionAfterTypeReference() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/expressionAfterTypeReference/forbidExpressionAfterTypeReference.kt");
+            }
+        }
+
         @Nested
         @TestMetadata("compiler/testData/diagnostics/tests/extensions")
         @TestDataPath("$PROJECT_ROOT")

compiler/tests-gen/org/jetbrains/kotlin/parsing/ParsingTestGenerated.java

@@ -2396,6 +2396,11 @@ public class ParsingTestGenerated extends AbstractParsingTest {
                 runTest("compiler/testData/psi/recovery/SameLineStatementRecovery.kt");
             }
 
+            @TestMetadata("TypeParameterBeforeEqualSign.kt")
+            public void testTypeParameterBeforeEqualSign() throws Exception {
+                runTest("compiler/testData/psi/recovery/TypeParameterBeforeEqualSign.kt");
+            }
+
             @TestMetadata("UnfinishedExtension.kt")
             public void testUnfinishedExtension() throws Exception {
                 runTest("compiler/testData/psi/recovery/UnfinishedExtension.kt");

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

@@ -262,6 +262,7 @@ enum class LanguageFeature(
     SynchronizedSuspendError(KOTLIN_1_8),
     EnableDfaWarningsInK2(KOTLIN_1_8, kind = OTHER), // KT-50965
     ReportNonVarargSpreadOnGenericCalls(KOTLIN_1_8, kind = BUG_FIX), // KT-48162
+    AllowExpressionAfterTypeReferenceWithoutSpacing(KOTLIN_1_8, kind = BUG_FIX), // KT-35811
 
     // 1.9