Array builtins proceed blithely on frozen arrays

test/mjsunit/object-freeze.js

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 296 matching lines @@
   get: function() { return 42 },
   set: function() { accessorDidRun = true },
   configurable: true,
   enumerable: true
 });
 obj.data = 'foo';
 assertTrue(%HasFastProperties(obj));
 Object.freeze(obj);
 assertTrue(%HasFastProperties(obj));
 assertTrue(Object.isFrozen(obj));
+
+// Test array built-in functions with freeze.
+obj = [1,2,3];
+Object.freeze(obj);
+// if frozen implies sealed, then the tests in object-seal.js are mostly
+// sufficient.
+assertTrue(Object.isSealed(obj));
+
+assertDoesNotThrow(function() { obj.push(); });
+assertDoesNotThrow(function() { obj.unshift(); });
+assertDoesNotThrow(function() { obj.splice(0,0); });
+assertTrue(Object.isFrozen(obj));
+
+// Verify that an item can't be changed with splice.
+assertThrows(function() { obj.splice(0,1,1); }, TypeError);
+
+// Verify that unshift() with no arguments will fail if it reifies from
+// the prototype into the object.
+obj = [1,,3];
+obj.__proto__[1] = 1;
+assertEquals(1, obj[1]);
+Object.freeze(obj);
+assertThrows(function() { obj.unshift(); }, TypeError);