Made ExpectationFilterChain immutable

src/core/ExpectationFilterChain.js

@@ -1,42 +1,52 @@
 getJasmineRequireObj().ExpectationFilterChain = function() {
-  function ExpectationFilterChain() {
-    this.filters_ = [];
+  function ExpectationFilterChain(maybeFilter, prev) {
+    this.filter_ = maybeFilter;
+    this.prev_ = prev;
   }
 
   ExpectationFilterChain.prototype.addFilter = function(filter) {
-    this.filters_.push(filter);
+    return new ExpectationFilterChain(filter, this);
   };
 
   ExpectationFilterChain.prototype.selectComparisonFunc = function(matcher) {
-    return this.callFirst_('selectComparisonFunc', arguments);
+    return this.callFirst_('selectComparisonFunc', arguments).result;
   };
 
   ExpectationFilterChain.prototype.buildFailureMessage = function(result, matcherName, args, util) {
-    return this.callFirst_('buildFailureMessage', arguments);
+    return this.callFirst_('buildFailureMessage', arguments).result;
   };
 
   ExpectationFilterChain.prototype.modifyFailureMessage = function(msg) {
-    var i;
+    if (this.prev_) {
+      msg = this.prev_.modifyFailureMessage(msg);
+    }
 
-    for (i = this.filters_.length - 1; i >= 0; i--) {
-      if (this.filters_[i].modifyFailureMessage) {
-        msg = this.filters_[i].modifyFailureMessage(msg);
-      }
+    if (this.filter_ && this.filter_.modifyFailureMessage) {
+      msg = this.filter_.modifyFailureMessage(msg);
     }
 
     return msg;
   };
 
   ExpectationFilterChain.prototype.callFirst_ = function(fname, args) {
-    var i, filter;
+    var prevResult;
 
-    for (i = 0; i < this.filters_.length; i++) {
-      filter = this.filters_[i];
+    if (this.prev_) {
+      prevResult = this.prev_.callFirst_(fname, args);
 
-      if (filter[fname]) {
-        return filter[fname].apply(filter, args);
+      if (prevResult.found) {
+        return prevResult;
       }
     }
+
+    if (this.filter_ && this.filter_[fname]) {
+      return {
+        found: true,
+        result: this.filter_[fname].apply(this.filter_, args)
+      };
+    }
+
+    return {found: false};
   };
 
   return ExpectationFilterChain;