Extend test coverage for JSON.stringify's slow path.

test/mjsunit/json2.js

Index: test/mjsunit/json2.js
diff --git a/test/mjsunit/json2.js b/test/mjsunit/json2.js
index 4c0b8f58c8ef6a9cc0ee7aba360f0a48fc0e04fe..6a720517bb26d3339a1c56c541db36580456caee 100644
--- a/test/mjsunit/json2.js
+++ b/test/mjsunit/json2.js
@@ -30,8 +30,14 @@
 // Test JSON.stringify on the global object.
 var a = 12345;
 assertTrue(JSON.stringify(this).indexOf('"a":12345') > 0);
+assertTrue(JSON.stringify(this, null, 0).indexOf('"a":12345') > 0);
 
 // Test JSON.stringify of array in dictionary mode.
+function TestStringify(expected, input) {
+  assertEquals(expected, JSON.stringify(input));
+  assertEquals(expected, JSON.stringify(input, null, 0));
+}
+
 var array_1 = [];
 var array_2 = [];
 array_1[100000] = 1;
@@ -42,25 +48,25 @@ for (var i = 0; i < 100000; i++) {
 }
 expected_1 = '[' + nulls + '1]';
 expected_2 = '[' + nulls + 'null]';
-assertEquals(expected_1, JSON.stringify(array_1));
-assertEquals(expected_2, JSON.stringify(array_2));
+TestStringify(expected_1, array_1);
+TestStringify(expected_2, array_2);
 
 // Test JSValue with custom prototype.
 var num_wrapper = Object(42);
 num_wrapper.__proto__ = { __proto__: null,
                           toString: function() { return true; } };
-assertEquals('1', JSON.stringify(num_wrapper));
+TestStringify('1', num_wrapper);
 
 var str_wrapper = Object('2');
 str_wrapper.__proto__ = { __proto__: null,
                           toString: function() { return true; } };
-assertEquals('"true"', JSON.stringify(str_wrapper));
+TestStringify('"true"', str_wrapper);
 
 var bool_wrapper = Object(false);
 bool_wrapper.__proto__ = { __proto__: null,
                            toString: function() { return true; } };
 // Note that toString function is not evaluated here!
-assertEquals('false', JSON.stringify(bool_wrapper));
+TestStringify('false', bool_wrapper);
 
 // Test getters.
 var counter = 0;
@@ -68,8 +74,8 @@ var getter_obj = { get getter() {
                          counter++;
                          return 123;
                        } };
-assertEquals('{"getter":123}', JSON.stringify(getter_obj));
-assertEquals(1, counter);
+TestStringify('{"getter":123}', getter_obj);
+assertEquals(2, counter);
 
 // Test toJSON function.
 var tojson_obj = { toJSON: function() {
@@ -77,8 +83,8 @@ var tojson_obj = { toJSON: function() {
                              return [1, 2];
                            },
                    a: 1};
-assertEquals('[1,2]', JSON.stringify(tojson_obj));
-assertEquals(2, counter);
+TestStringify('[1,2]', tojson_obj);
+assertEquals(4, counter);
 
 // Test that we don't recursively look for the toJSON function.
 var tojson_proto_obj = { a: 'fail' };
@@ -86,7 +92,7 @@ tojson_proto_obj.__proto__ = { toJSON: function() {
                                          counter++;
                                          return tojson_obj;
                                        } };
-assertEquals('{"a":1}', JSON.stringify(tojson_proto_obj));
+TestStringify('{"a":1}', tojson_proto_obj);
 
 // Test toJSON produced by a getter.
 var tojson_via_getter = { get toJSON() {
@@ -96,43 +102,44 @@ var tojson_via_getter = { get toJSON() {
                                        };
                               },
                           a: 1 };
-assertEquals('321', JSON.stringify(tojson_via_getter));
+TestStringify('321', tojson_via_getter);
 
 // Test toJSON with key.
 tojson_obj = { toJSON: function(key) { return key + key; } };
 var tojson_with_key_1 = { a: tojson_obj, b: tojson_obj };
-assertEquals('{"a":"aa","b":"bb"}', JSON.stringify(tojson_with_key_1));
+TestStringify('{"a":"aa","b":"bb"}', tojson_with_key_1);
 var tojson_with_key_2 = [ tojson_obj, tojson_obj ];
-assertEquals('["00","11"]', JSON.stringify(tojson_with_key_2));
+TestStringify('["00","11"]', tojson_with_key_2);
 
 // Test toJSON with exception.
 var tojson_ex = { toJSON: function(key) { throw "123" } };
 assertThrows(function() { JSON.stringify(tojson_ex); });
+assertThrows(function() { JSON.stringify(tojson_ex, null, 0); });
 
 // Test toJSON with access to this.
 var obj = { toJSON: function(key) { return this.a + key; }, a: "x" };
-assertEquals('{"y":"xy"}', JSON.stringify({y: obj}));
+TestStringify('{"y":"xy"}', {y: obj});
 
 // Test holes in arrays.
 var fast_smi = [1, 2, 3, 4];
 fast_smi.__proto__ = [7, 7, 7, 7];
 delete fast_smi[2];
 assertTrue(%HasFastSmiElements(fast_smi));
-assertEquals("[1,2,7,4]", JSON.stringify(fast_smi));
+TestStringify("[1,2,7,4]", fast_smi);
 
 var fast_double = [1.1, 2, 3, 4];
 fast_double.__proto__ = [7, 7, 7, 7];
 
 delete fast_double[2];
 assertTrue(%HasFastDoubleElements(fast_double));
-assertEquals("[1.1,2,7,4]", JSON.stringify(fast_double));
+TestStringify("[1.1,2,7,4]", fast_double);
 
 var fast_obj = [1, 2, {}, {}];
 fast_obj.__proto__ = [7, 7, 7, 7];
 
 delete fast_obj[2];
 assertTrue(%HasFastObjectElements(fast_obj));
-assertEquals("[1,2,7,{}]", JSON.stringify(fast_obj));
+TestStringify("[1,2,7,{}]", fast_obj);
 
 var getter_side_effect = { a: 1,
                            get b() {
@@ -146,8 +153,22 @@ var getter_side_effect = { a: 1,
 assertEquals('{"a":1,"b":2,"d":4}', JSON.stringify(getter_side_effect));
 assertEquals('{"b":2,"d":4,"e":5}', JSON.stringify(getter_side_effect));
 
+getter_side_effect = { a: 1,
+    get b() {
+      delete this.a;
+      delete this.c;
+      this.e = 5;
+      return 2;
+    },
+    c: 3,
+    d: 4 };
+assertEquals('{"a":1,"b":2,"d":4}',
+             JSON.stringify(getter_side_effect, null, 0));
+assertEquals('{"b":2,"d":4,"e":5}',
+             JSON.stringify(getter_side_effect, null, 0));
+
 var non_enum = {};
 non_enum.a = 1;
 Object.defineProperty(non_enum, "b", { value: 2, enumerable: false });
 non_enum.c = 3;
-assertEquals('{"a":1,"c":3}', JSON.stringify(non_enum));
+TestStringify('{"a":1,"c":3}', non_enum);