Refactor prettyPrinter to work with immutable objects

[#50766813][#266]

spec/core/PrettyPrintSpec.js

@@ -63,6 +63,13 @@ describe("j$.pp", function () {
     }
   });
 
+  it("should stringify immutable circular objects", function(){
+    var frozenObject = {foo: {bar: 'baz'}};
+    frozenObject.circular = frozenObject;
+    frozenObject = Object.freeze(frozenObject);
+    expect(j$.pp(frozenObject)).toEqual("{ foo : { bar : 'baz' }, circular : <circular reference: Object> }");
+  });
+
   it("should stringify RegExp objects properly", function() {
     expect(j$.pp(/x|y|z/)).toEqual("/x|y|z/");
   });

spec/performance/large_object_test.js

@@ -0,0 +1,36 @@
+describe('Printing a big object', function(){
+  var bigObject;
+  function rand(upper) {
+    return Math.round(upper * Math.random());
+  }
+
+  function generateObject(level) {
+    var object = {};
+
+    for (var i = 0; i < 50; i++) {
+      var decide = rand(2);
+      switch (decide) {
+        case 0:
+          object["cycle" + i] = object;
+        break;
+        case 1:
+          object["number" + i] = rand(100);
+        break;
+        case 2:
+          if (level < 3) {
+          object["nesting" + i] = generateObject(level + 1);
+        }
+        break;
+      }
+
+    }
+
+    return object;
+  }
+
+  it('takes a resonable amount of time', function(){
+    bigObject = generateObject(0);
+    expect(j$.pp(bigObject)).toMatch(/cycle/);
+  });
+});
+