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/);
+  });
+});
+

src/core/PrettyPrinter.js

@@ -2,6 +2,7 @@ getJasmineRequireObj().pp = function(j$) {
 
   function PrettyPrinter() {
     this.ppNestLevel_ = 0;
+    this.seen = [];
   }
 
   PrettyPrinter.prototype.format = function(value) {
@@ -29,16 +30,16 @@ getJasmineRequireObj().pp = function(j$) {
         this.emitScalar('HTMLNode');
       } else if (value instanceof Date) {
         this.emitScalar('Date(' + value + ')');
-      } else if (value.__Jasmine_been_here_before__) {
+      } else if (j$.util.arrayContains(this.seen, value)) {
         this.emitScalar('<circular reference: ' + (j$.isArray_(value) ? 'Array' : 'Object') + '>');
       } else if (j$.isArray_(value) || j$.isA_('Object', value)) {
-        value.__Jasmine_been_here_before__ = true;
+        this.seen.push(value);
         if (j$.isArray_(value)) {
           this.emitArray(value);
         } else {
           this.emitObject(value);
         }
-        delete value.__Jasmine_been_here_before__;
+        this.seen.pop();
       } else {
         this.emitScalar(value.toString());
       }
@@ -50,7 +51,6 @@ getJasmineRequireObj().pp = function(j$) {
   PrettyPrinter.prototype.iterateObject = function(obj, fn) {
     for (var property in obj) {
       if (!Object.prototype.hasOwnProperty.call(obj, property)) { continue; }
-      if (property == '__Jasmine_been_here_before__') { continue; }
       fn(property, obj.__lookupGetter__ ? (!j$.util.isUndefined(obj.__lookupGetter__(property)) &&
           obj.__lookupGetter__(property) !== null) : false);
     }

src/core/util.js

@@ -30,5 +30,15 @@ getJasmineRequireObj().util = function() {
     return obj === void 0;
   };
 
+  util.arrayContains = function(array, search) {
+    var i = array.length;
+    while (i--) {
+      if (array[i] == search) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   return util;
 };