GROOVY-11877: anon. inner class is never static

Author: eric-milles

src/main/java/org/codehaus/groovy/ast/InnerClassNode.java

@@ -20,6 +20,8 @@
 
 import org.objectweb.asm.Opcodes;
 
+import java.util.Collections;
+
 /**
  * Represents an inner class definition.
  */
@@ -75,11 +77,31 @@ public void setVariableScope(VariableScope scope) {
         this.scope = scope;
     }
 
+    @Override
+    public boolean isSealed() {
+        return !isAnonymous() && super.isSealed(); // JLS 15.9.5
+    }
+
     public boolean isAnonymous() {
         return anonymous;
     }
 
-    public void setAnonymous(boolean anonymous) {
-        this.anonymous = anonymous;
+    public void setAnonymous(final boolean anonymous) {
+        if (this.anonymous != anonymous) {
+            if (anonymous) { // JLS 15.9.5
+                this.anonymous = true;
+
+                // GROOVY-11877
+                int modifiers = getModifiers();
+                modifiers &= ~Opcodes.ACC_STATIC;
+                modifiers &= ~Opcodes.ACC_ABSTRACT;
+                if (!isEnum()) modifiers &= ~Opcodes.ACC_FINAL;
+                setModifiers(modifiers);
+
+                setPermittedSubclasses(Collections.emptyList());
+            } else {
+                throw new IllegalArgumentException("cannot demote anon. inner class");
+            }
+        }
     }
 }

src/test/groovy/gls/innerClass/InnerClassTest.groovy

@@ -89,6 +89,34 @@ final class InnerClassTest {
         '''
     }
 
+    // GROOVY-11877
+    @Test
+    void testInnerAIC2() {
+        assertScript '''import java.lang.reflect.Modifier
+            interface I {
+                def bar = new Object[1]
+                def foo = new Runnable() {
+                    @Override
+                    void run() {
+                        bar[0] = true
+                    }
+                }
+            }
+
+            def obj = I.foo
+            assert !I.bar[0]
+            obj.run()
+            assert  I.bar[0]
+
+            def aic = obj.getClass()
+            assert aic.getName() == 'I$1'
+            assert aic.getEnclosingClass().getName() == 'I'
+            assert !Modifier.isFinal   (aic.getModifiers())
+            assert !Modifier.isStatic  (aic.getModifiers())
+            assert !Modifier.isAbstract(aic.getModifiers())
+        '''
+    }
+
     // GROOVY-11854
     @Test
     void testScriptAIC() {