GROOVY-9763

Author: eric-milles

base-test/org.eclipse.jdt.groovy.core.tests.compiler/src/org/eclipse/jdt/groovy/core/tests/basic/TraitsTests.java

@@ -2674,4 +2674,29 @@ public void testTraits9760() {
 
         runConformTest(sources, "works");
     }
+
+    @Test
+    public void testTraits9763() {
+        //@formatter:off
+        String[] sources = {
+            "Script.groovy",
+            "@groovy.transform.CompileStatic\n" +
+            "void test() {\n" +
+            "  C.m({ -> print 'works'; return 0 })\n" +
+            "}\n" +
+            "test()\n",
+
+            "C.groovy",
+            "class C implements T {\n" +
+            "}\n",
+
+            "T.groovy",
+            "trait T {\n" +
+            "  static <U> U m(Closure<U> callable) { callable.call() }\n" +
+            "}\n",
+        };
+        //@formatter:on
+
+        runConformTest(sources, "works");
+    }
 }

base/org.codehaus.groovy25/src/org/codehaus/groovy/transform/trait/TraitComposer.java

@@ -143,12 +143,18 @@ private static void applyTrait(final ClassNode trait, final ClassNode cNode, fin
                 Parameter[] origParams = new Parameter[helperMethodParams.length - 1];
                 Parameter[] params = new Parameter[helperMethodParams.length - 1];
                 System.arraycopy(methodNode.getParameters(), 1, params, 0, params.length);
+                /* GRECLIPSE edit -- GROOVY-9763
                 Map<String,ClassNode> methodGenericsSpec = new LinkedHashMap<String, ClassNode>(genericsSpec);
                 MethodNode originalMethod = trait.getMethod(name, params);
                 // Original method may be null for the case of private or static methods
                 if (originalMethod!=null) {
                     methodGenericsSpec = GenericsUtils.addMethodGenerics(originalMethod, methodGenericsSpec);
                 }
+                */
+                MethodNode originalMethod = trait.getMethod(name, params);
+                Map<String, ClassNode> methodGenericsSpec = GenericsUtils.addMethodGenerics(
+                        originalMethod != null ? originalMethod : methodNode, genericsSpec);
+                // GRECLIPSE end
                 for (int i = 1; i < helperMethodParams.length; i++) {
                     Parameter parameter = helperMethodParams[i];
                     ClassNode originType = parameter.getOriginType();

base/org.codehaus.groovy30/src/org/codehaus/groovy/transform/trait/TraitComposer.java

@@ -142,8 +142,13 @@ private static void applyTrait(final ClassNode trait, final ClassNode cNode, fin
                 Parameter[] params = new Parameter[nParams - 1];
                 System.arraycopy(methodNode.getParameters(), 1, params, 0, params.length);
                 MethodNode originalMethod = trait.getMethod(name, params);
+                /* GRECLIPSE edit -- GROOVY-9763
                 Map<String, ClassNode> methodGenericsSpec = Optional.ofNullable(originalMethod)
                     .map(m -> GenericsUtils.addMethodGenerics(m, genericsSpec)).orElse(genericsSpec);
+                */
+                Map<String, ClassNode> methodGenericsSpec = GenericsUtils.addMethodGenerics(
+                        Optional.ofNullable(originalMethod).orElse(methodNode), genericsSpec);
+                // GRECLIPSE end
                 for (int i = 1; i < nParams; i += 1) {
                     Parameter parameter = helperMethodParams[i];
                     ClassNode originType = parameter.getOriginType();