Exception fix: diagnose an error for a generic type which is a subtype of itself, a set of tests #EA-64453 Fixed

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

@@ -249,6 +249,8 @@ public interface Errors {
     DiagnosticFactory0<JetDeclaration> TYPE_PARAMETERS_NOT_ALLOWED
             = DiagnosticFactory0.create(ERROR, TYPE_PARAMETERS_OR_DECLARATION_SIGNATURE);
 
+    DiagnosticFactory0<PsiElement> CYCLIC_GENERIC_UPPER_BOUND = DiagnosticFactory0.create(ERROR);
+
     // Members
 
     DiagnosticFactory0<JetModifierListOwner> PACKAGE_MEMBER_CANNOT_BE_PROTECTED =

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

@@ -421,6 +421,7 @@ public class DefaultErrorMessages {
 
         MAP.put(TYPE_MISMATCH_IN_RANGE, "Type mismatch: incompatible types of range and element checked in it");
         MAP.put(CYCLIC_INHERITANCE_HIERARCHY, "There's a cycle in the inheritance hierarchy for this type");
+        MAP.put(CYCLIC_GENERIC_UPPER_BOUND, "Type parameter has itself as an upper bound");
 
         MAP.put(MANY_CLASSES_IN_SUPERTYPE_LIST, "Only one class may appear in a supertype list");
         MAP.put(SUPERTYPE_NOT_A_CLASS_OR_TRAIT, "Only classes and interfaces may serve as supertypes");

compiler/frontend/src/org/jetbrains/kotlin/resolve/DescriptorResolver.java

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.descriptors.annotations.Annotations;
 import org.jetbrains.kotlin.descriptors.impl.*;
 import org.jetbrains.kotlin.diagnostics.DiagnosticFactory1;
+import org.jetbrains.kotlin.diagnostics.Errors;
 import org.jetbrains.kotlin.lexer.JetKeywordToken;
 import org.jetbrains.kotlin.lexer.JetModifierKeywordToken;
 import org.jetbrains.kotlin.lexer.JetTokens;
@@ -476,6 +477,10 @@ public class DescriptorResolver {
             JetTypeReference extendsBound = jetTypeParameter.getExtendsBound();
             if (extendsBound != null) {
                 JetType type = typeResolver.resolveType(scope, extendsBound, trace, false);
+                if (type.getConstructor().equals(typeParameterDescriptor.getTypeConstructor())) {
+                    trace.report(Errors.CYCLIC_GENERIC_UPPER_BOUND.on(extendsBound));
+                    type = ErrorUtils.createErrorType("Cyclic upper bound: " + type);
+                }
                 typeParameterDescriptor.addUpperBound(type);
                 deferredUpperBoundCheckerTasks.add(new UpperBoundCheckerTask(extendsBound, type));
             }

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBound.kt

@@ -0,0 +1,3 @@
+// !DIAGNOSTICS: -MUST_BE_INITIALIZED
+fun <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> foo() {}
+val <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> prop

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBound.txt

@@ -0,0 +1,4 @@
+package
+
+internal val </*0*/ T : [ERROR : Cyclic upper bound: T?]> prop: [ERROR : No type, no body]
+internal fun </*0*/ T : [ERROR : Cyclic upper bound: T?]> foo(): kotlin.Unit

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundLocal.kt

@@ -0,0 +1,4 @@
+fun bar() {
+    fun <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> foo() {}
+    foo()
+}

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundLocal.txt

@@ -0,0 +1,3 @@
+package
+
+internal fun bar(): kotlin.Unit

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundMember.kt

@@ -0,0 +1,5 @@
+// !DIAGNOSTICS: -MUST_BE_INITIALIZED_OR_BE_ABSTRACT
+class My {
+    fun <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> foo() {}
+    val <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> prop: T
+}

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundMember.txt

@@ -0,0 +1,10 @@
+package
+
+internal final class My {
+    public constructor My()
+    internal final val </*0*/ T : [ERROR : Cyclic upper bound: T?]> prop: [ERROR : ?]
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    internal final fun </*0*/ T : [ERROR : Cyclic upper bound: T?]> foo(): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundNotNull.kt

@@ -0,0 +1,3 @@
+// !DIAGNOSTICS: -MUST_BE_INITIALIZED
+fun <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T<!>> foo() {}
+val <T: <!CYCLIC_GENERIC_UPPER_BOUND!>T?<!>> prop: T

compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundNotNull.txt

@@ -0,0 +1,4 @@
+package
+
+internal val </*0*/ T : [ERROR : Cyclic upper bound: T?]> prop: [ERROR : ?]
+internal fun </*0*/ T : [ERROR : Cyclic upper bound: T]> foo(): kotlin.Unit

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

@@ -10224,6 +10224,30 @@ public class JetDiagnosticsTestGenerated extends AbstractJetDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("itselfAsUpperBound.kt")
+            public void testItselfAsUpperBound() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/regressions/itselfAsUpperBound.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("itselfAsUpperBoundLocal.kt")
+            public void testItselfAsUpperBoundLocal() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundLocal.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("itselfAsUpperBoundMember.kt")
+            public void testItselfAsUpperBoundMember() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundMember.kt");
+                doTest(fileName);
+            }
+
+            @TestMetadata("itselfAsUpperBoundNotNull.kt")
+            public void testItselfAsUpperBoundNotNull() throws Exception {
+                String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/regressions/itselfAsUpperBoundNotNull.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("Jet11.kt")
             public void testJet11() throws Exception {
                 String fileName = JetTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/regressions/Jet11.kt");