Fix for #1077: T[] and Object[] cannot accept primitive arrays

Author: eric-milles

base-test/org.eclipse.jdt.groovy.core.tests.builder/src/org/eclipse/jdt/core/groovy/tests/search/DGMInferencingTests.java

@@ -587,6 +587,31 @@ public void testDGM45a() {
         }
     }
 
+    @Test
+    public void testDGM45b() {
+        String contents =
+            //@formatter:off
+            "String[] array = []\n" +
+            "array.sort { a, b ->\n" +
+            "  a.trim() <=> b.trim()\n" +
+            "}\n";
+            //@formatter:on
+
+        assertDeclType(contents, "sort", "org.codehaus.groovy.runtime.DefaultGroovyMethods");
+    }
+
+    @Test // https://github.com/groovy/groovy-eclipse/issues/1077
+    public void testDGM45c() {
+        String contents =
+            //@formatter:off
+            "char[] array = []\n" +
+            "array.sort()\n";
+            //@formatter:on
+
+        int offset = contents.indexOf("sort");
+        assertUnknownConfidence(contents, offset, offset + 4);
+    }
+
     @Test
     public void testDGM46() {
         String contents =

base/org.eclipse.jdt.groovy.core/src/org/eclipse/jdt/groovy/core/util/GroovyUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2009-2019 the original author or authors.
+ * Copyright 2009-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -397,8 +397,12 @@ private static boolean isAssignable(boolean array, ClassNode source, ClassNode t
         } else*/ if (target.isInterface()) {
             result = GeneralUtils.isOrImplements(source, target);
         } else if (array) {
-            // Object or Object[] is universal receiver for an array
-            result = ClassHelper.OBJECT_TYPE.equals(target) || source.isDerivedFrom(target);
+            if (target.isGenericsPlaceHolder() || target.equals(ClassHelper.OBJECT_TYPE)) {
+                // T[] or Object[] cannot accept a primitive array
+                result = !ClassHelper.isPrimitiveType(source);
+            } else {
+                result = source.isDerivedFrom(target);
+            }
         } else {
             result = getWrapperTypeIfPrimitive(source).isDerivedFrom(getWrapperTypeIfPrimitive(target));
         }