GROOVY-10082

Author: eric-milles

base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/xform/TypeCheckedTests.java

@@ -2684,6 +2684,26 @@ public void testTypeChecked10080() {
         runConformTest(sources, "42");
     }
 
+    @Test
+    public void testTypeChecked10082() {
+        //@formatter:off
+        String[] sources = {
+            "Main.groovy",
+            "class A {}\n" +
+            "class B extends A {}\n" +
+            "@groovy.transform.TypeChecked\n" +
+            "void test() {\n" +
+            "  Closure<A> c = { -> new B() }\n" +
+            "  print(c() instanceof A)\n" +
+            "  print(c() instanceof B)\n" +
+            "}\n" +
+            "test()\n",
+        };
+        //@formatter:on
+
+        runConformTest(sources, "truetrue");
+    }
+
     @Test
     public void testTypeChecked10088() {
         //@formatter:off

base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java

@@ -2639,7 +2639,7 @@ private ClassNode infer(ClassNode target, ClassNode source) {
 
     protected ClassNode checkReturnType(final ReturnStatement statement) {
         Expression expression = statement.getExpression();
-        /* GRECLIPSE edit -- GROOVY-9907, GROOVY-9971, GROOVY-9995, GROOVY-10080
+        /* GRECLIPSE edit -- GROOVY-9907, GROOVY-9971, GROOVY-9995, GROOVY-10080, GROOVY-10082
         ClassNode type = getType(expression);
 
         if (typeCheckingContext.getEnclosingClosure() != null) {
@@ -2663,6 +2663,10 @@ protected ClassNode checkReturnType(final ReturnStatement statement) {
             }
             if (STRING_TYPE.equals(inferredReturnType) && StaticTypeCheckingSupport.isGStringOrGStringStringLUB(type)) {
                 type = STRING_TYPE; // implicit "toString()" before return
+            } else if (inferredReturnType != null && !inferredReturnType.isGenericsPlaceHolder()
+                    && !type.isUsingGenerics() && !type.equals(inferredReturnType) && (inferredReturnType.isInterface()
+                            ? type.implementsInterface(inferredReturnType) : type.isDerivedFrom(inferredReturnType))) {
+                type = inferredReturnType; // allow simple covariance
             }
             return type;
         }

base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java

@@ -2392,13 +2392,17 @@ protected ClassNode checkReturnType(final ReturnStatement statement) {
             type = getType(expression);
         }
         if (typeCheckingContext.getEnclosingClosure() != null) {
-            // GRECLIPSE add -- GROOVY-9971, GROOVY-9995, GROOVY-10080
+            // GRECLIPSE add -- GROOVY-9971, GROOVY-9995, GROOVY-10080, GROOVY-10082
             ClassNode inferredReturnType = getInferredReturnType(typeCheckingContext.getEnclosingClosure().getClosureExpression());
             if (expression instanceof ConstructorCallExpression) {
                 inferDiamondType((ConstructorCallExpression) expression, inferredReturnType != null ? inferredReturnType : DYNAMIC_TYPE);
             }
             if (STRING_TYPE.equals(inferredReturnType) && StaticTypeCheckingSupport.isGStringOrGStringStringLUB(type)) {
                 type = STRING_TYPE; // implicit "toString()" before return
+            } else if (inferredReturnType != null && !inferredReturnType.isGenericsPlaceHolder()
+                    && !type.isUsingGenerics() && !type.equals(inferredReturnType) && (inferredReturnType.isInterface()
+                            ? type.implementsInterface(inferredReturnType) : type.isDerivedFrom(inferredReturnType))) {
+                type = inferredReturnType; // allow simple covariance
             }
             // GRECLIPSE end
             return type;

base/org.codehaus.groovy40/src/org/codehaus/groovy/transform/stc/StaticTypeCheckingVisitor.java

@@ -2305,7 +2305,7 @@ protected ClassNode checkReturnType(final ReturnStatement statement) {
             type = getType(expression);
         }
         if (typeCheckingContext.getEnclosingClosure() != null) {
-            /* GRECLIPSE edit -- GROOVY-9971, GROOVY-9995, GROOVY-10080
+            /* GRECLIPSE edit -- GROOVY-9971, GROOVY-9995, GROOVY-10080, GROOVY-10082
             if (expression instanceof ConstructorCallExpression) {
                 ClassNode inferredClosureReturnType = getInferredReturnType(typeCheckingContext.getEnclosingClosure().getClosureExpression());
                 if (inferredClosureReturnType != null) inferDiamondType((ConstructorCallExpression) expression, inferredClosureReturnType);
@@ -2317,6 +2317,10 @@ protected ClassNode checkReturnType(final ReturnStatement statement) {
             }
             if (STRING_TYPE.equals(inferredReturnType) && isGStringOrGStringStringLUB(type)) {
                 type = STRING_TYPE; // convert GString to String at the point of return
+            } else if (inferredReturnType != null && !inferredReturnType.isGenericsPlaceHolder()
+                    && !type.isUsingGenerics() && !type.equals(inferredReturnType) && (inferredReturnType.isInterface()
+                            ? type.implementsInterface(inferredReturnType) : type.isDerivedFrom(inferredReturnType))) {
+                type = inferredReturnType; // allow simple covariance
             }
             // GRECLIPSE end
             return type;