fixed bug where mustache had access to data from previous runs

mustache.js

@@ -1,230 +1,235 @@
 /*
   Shamless port of http://github.com/defunkt/mustache
-  by Jan Lehnardt <jan@apache.org>
+  by Jan Lehnardt <jan@apache.org>, Alexander Lang <alex@upstream-berlin.com>
 
   Thanks @defunkt for the awesome code.
   
   See http://github.com/defunkt/mustache for more info.
 */
 
-var Mustache = {
-  name: "mustache.js",
-  version: "0.1",
-  context: {},
-  otag: "{{",
-  ctag: "}}",
-
-  /*
-    Public method. Turns a template and view into HTML
-  */
-  to_html: function(template, view) {
-    return this.render(template, view);
-  },
-
-  // Private Methods
-  render: function(template, view) {
-    // fail fast
-    if(template.indexOf(this.otag) == -1) {
-      return template;
-    }
+var Mustache = function() {
+  var Renderer = function() {};
+  
+  Renderer.prototype = {
+    otag: "{{",
+    ctag: "}}",
+    
+    render: function(template, view) {
+      // fail fast
+      if(template.indexOf(this.otag) == -1) {
+        return template;
+      }
 
-    // keep context around for recursive calls
-    this.context = context = this.merge((this.context || {}), this.create_context(view));
+      // keep context around for recursive calls
+      this.context = context = this.merge((this.context || {}), this.create_context(view));
 
-    // first, render all sections 
-    var html = this.render_section(template);
+      // first, render all sections 
+      var html = this.render_section(template);
 
-    // restore context, recursion might have messed it up
-    this.context = context;
+      // restore context, recursion might have messed it up
+      this.context = context;
 
-    // finally, render tags
-    
-    // render until all is rendered
-    return this.render_tags(html);
-  },
-  
-  create_context: function(_context) {
-    if(this.is_object(_context)) {
-      return _context;
-    } else {
-      return {'.': _context};
-    }
-  },
-  
-  is_object: function(a) {
-    return a && typeof a == 'object'
-  },
-  
-  /* 
-    Tries to find a partial in the global scope and render it
-  */
-  render_partial: function(name) {
-    // FIXME: too hacky
-    var evil_name = eval(name)
-    switch(typeof evil_name) {
-      case "string": // a tring partial, we simply render
-        return this.to_html(evil_name, "");
-      case "object": // a view partial needs a `name_template` template
-        var tpl = name + "_template";
-        return this.to_html(eval(tpl), evil_name);
-      default: // should not happen #famouslastwords
-        throw("Unknown partial type.");
-    }
-  },
+      // finally, render tags
 
-  /*
-    Renders boolean and enumerable sections
-  */
-  render_section: function(template) {
-    if(template.indexOf(this.otag + "#") == -1) {
-      return template;
-    }
-    var that = this;
-    var regex = new RegExp(this.otag + "\\#(.+)" + this.ctag +
-      "\\s*([\\s\\S]+)" + this.otag + "\\/\\1" + this.ctag + "\\s*", "mg");
-
-    // for each {{#foo}}{{/foo}} section do...
-    return template.replace(regex, function(match, name, content) {
-        var value = that.find(name);
-        if(that.is_array(value)) { // Enumerable, Let's loop!
-          return value.map(function(row) {
-            return that.render(content, row);
-          }).join('');
-        } else if(value) { // boolean section
-          return that.render(content);
-        } else {
-          return "";
-        }
+      // render until all is rendered
+      return this.render_tags(html);
+    },
+
+    create_context: function(_context) {
+      if(this.is_object(_context)) {
+        return _context;
+      } else {
+        return {'.': _context};
+      }
+    },
+
+    is_object: function(a) {
+      return a && typeof a == 'object'
+    },
+
+    /* 
+      Tries to find a partial in the global scope and render it
+    */
+    render_partial: function(name) {
+      // FIXME: too hacky
+      var evil_name = eval(name)
+      switch(typeof evil_name) {
+        case "string": // a tring partial, we simply render
+          return this.render(evil_name, "");
+        case "object": // a view partial needs a `name_template` template
+          var tpl = name + "_template";
+          return this.render(eval(tpl), evil_name);
+        default: // should not happen #famouslastwords
+          throw("Unknown partial type.");
       }
-    );
-  },
-
-  /*
-    Replace {{foo}} and friends with values from our view
-  */
-  render_tags: function(template) {
-    var pop_first = function(lines) {
-      var lines_array = lines.split("\n");
-      lines_array.shift();
-      return lines_array.join("\n");
-    };
-
-    var new_regex = function() {
-      return new RegExp(that.otag + 
-        "(=|!|<|\\{)?([^\/#]+?)\\1?" + that.ctag + "+", "m");
-    };
-
-    // tit for tat
-    var that = this;
-
-    regex = new_regex();
-    var lines = template;
-
-    // for each {{(!<{)?foo}} tag, do...
-    while(regex.test(lines)) {
-      template = template.replace(regex, function (match, operator, name) {
-        switch(operator) {
-          case "!": // ignore comments
-            return match;
-          case "=": // set new delimiters
-            that.set_delimiters(name);
+    },
+
+    /*
+      Renders boolean and enumerable sections
+    */
+    render_section: function(template) {
+      if(template.indexOf(this.otag + "#") == -1) {
+        return template;
+      }
+      var that = this;
+      var regex = new RegExp(this.otag + "\\#(.+)" + this.ctag +
+        "\\s*([\\s\\S]+)" + this.otag + "\\/\\1" + this.ctag + "\\s*", "mg");
+
+      // for each {{#foo}}{{/foo}} section do...
+      return template.replace(regex, function(match, name, content) {
+          var value = that.find(name);
+          if(that.is_array(value)) { // Enumerable, Let's loop!
+            return value.map(function(row) {
+              return that.render(content, row);
+            }).join('');
+          } else if(value) { // boolean section
+            return that.render(content);
+          } else {
             return "";
-          case "<": // render partial
-            return that.render_partial(name);
-          case "{": // the triple mustache is unescaped
-            return that.find(name);
-          default: // escape the value
-            return that.escape(that.find(name));
+          }
         }
-      }, this);
-      regex = new_regex();
-      lines = pop_first(lines);
-    } 
-    return template;
-  },
-
-  set_delimiters: function(delimiters) {
-    var dels = delimiters.split(" ");
-    this.otag = this.escape_regex(dels[0]);
-    this.ctag = this.escape_regex(dels[1]);
-  },
-
-  escape_regex: function(text) {
-    // thank you Simon Willison
-    if(!arguments.callee.sRE) {
-      var specials = [
-        '/', '.', '*', '+', '?', '|',
-        '(', ')', '[', ']', '{', '}', '\\'
-      ];
-      arguments.callee.sRE = new RegExp(
-        '(\\' + specials.join('|\\') + ')', 'g'
       );
-    }
-  return text.replace(arguments.callee.sRE, '\\$1');
-  },
-
-  /*
-    find `name` in current `context`. That is find me a value 
-    from the view object
-  */
-  find: function(name) {
-    name = this.trim(name);
-    var context = this.context;
-    if(typeof context[name] === "function") {
-      return context[name].apply(context);
-    }
-    if(context[name] !== undefined) {
-      return context[name];
-    }
-    throw("Can't find " + name + " in " + context);
-  },
-
-  // Utility methods
-
-  /*
-    Does away with nasty characters
-  */
-  escape: function(s) {
-    return s.toString().replace(/[&"<>\\]/g, function(s) {
-      switch(s) {
-        case "&": return "&amp;";
-        case "\\": return "\\\\";;
-        case '"': return '\"';;
-        case "<": return "&lt;";
-        case ">": return "&gt;";
-        default: return s;
+    },
+
+    /*
+      Replace {{foo}} and friends with values from our view
+    */
+    render_tags: function(template) {
+      var pop_first = function(lines) {
+        var lines_array = lines.split("\n");
+        lines_array.shift();
+        return lines_array.join("\n");
+      };
+
+      var new_regex = function() {
+        return new RegExp(that.otag + 
+          "(=|!|<|\\{)?([^\/#]+?)\\1?" + that.ctag + "+", "m");
+      };
+
+      // tit for tat
+      var that = this;
+
+      regex = new_regex();
+      var lines = template;
+
+      // for each {{(!<{)?foo}} tag, do...
+      while(regex.test(lines)) {
+        template = template.replace(regex, function (match, operator, name) {
+          switch(operator) {
+            case "!": // ignore comments
+              return match;
+            case "=": // set new delimiters
+              that.set_delimiters(name);
+              return "";
+            case "<": // render partial
+              return that.render_partial(name);
+            case "{": // the triple mustache is unescaped
+              return that.find(name);
+            default: // escape the value
+              return that.escape(that.find(name));
+          }
+        }, this);
+        regex = new_regex();
+        lines = pop_first(lines);
+      } 
+      return template;
+    },
+
+    set_delimiters: function(delimiters) {
+      var dels = delimiters.split(" ");
+      this.otag = this.escape_regex(dels[0]);
+      this.ctag = this.escape_regex(dels[1]);
+    },
+
+    escape_regex: function(text) {
+      // thank you Simon Willison
+      if(!arguments.callee.sRE) {
+        var specials = [
+          '/', '.', '*', '+', '?', '|',
+          '(', ')', '[', ']', '{', '}', '\\'
+        ];
+        arguments.callee.sRE = new RegExp(
+          '(\\' + specials.join('|\\') + ')', 'g'
+        );
       }
-    });
-  },
-
-  /*
-    Merges all properties of object `b` into object `a`. 
-    `b.property` overwrites a.property`
-  */
-  merge: function(a, b) {
-    for(var name in b) {
-      if(b.hasOwnProperty(name)) {
-        a[name] = b[name];
+    return text.replace(arguments.callee.sRE, '\\$1');
+    },
+
+    /*
+      find `name` in current `context`. That is find me a value 
+      from the view object
+    */
+    find: function(name) {
+      name = this.trim(name);
+      var context = this.context;
+      if(typeof context[name] === "function") {
+        return context[name].apply(context);
       }
+      if(context[name] !== undefined) {
+        return context[name];
+      }
+      throw("Can't find " + name + " in " + context);
+    },
+
+    // Utility methods
+
+    /*
+      Does away with nasty characters
+    */
+    escape: function(s) {
+      return s.toString().replace(/[&"<>\\]/g, function(s) {
+        switch(s) {
+          case "&": return "&amp;";
+          case "\\": return "\\\\";;
+          case '"': return '\"';;
+          case "<": return "&lt;";
+          case ">": return "&gt;";
+          default: return s;
+        }
+      });
+    },
+
+    /*
+      Merges all properties of object `b` into object `a`. 
+      `b.property` overwrites a.property`
+    */
+    merge: function(a, b) {
+      for(var name in b) {
+        if(b.hasOwnProperty(name)) {
+          a[name] = b[name];
+        }
+      }
+      return a;
+    },
+
+    /*
+      Thanks Doug Crockford
+      JavaScript — The Good Parts lists an alternative that works better with
+      frames. Frames can suck it, we use the simple version.
+    */
+    is_array: function(a) {
+      return (a &&
+        typeof a === 'object' &&
+        a.constructor === Array);
+    },
+
+    /*
+      Gets rid of leading and trailing whitespace
+    */
+    trim: function(s) {
+      return s.replace(/^\s*|\s*$/g, '');
+    }
+  };
+  
+  return({
+    name: "mustache.js",
+    version: "0.1",
+    
+    /*
+      Turns a template and view into HTML
+    */
+    to_html: function(template, view) {
+      return new Renderer().render(template, view);
     }
-    return a;
-  },
-
-  /*
-    Thanks Doug Crockford
-    JavaScript — The Good Parts lists an alternative that works better with
-    frames. Frames can suck it, we use the simple version.
-  */
-  is_array: function(a) {
-    return (a &&
-      typeof a === 'object' &&
-      a.constructor === Array);
-  },
-
-  /*
-    Gets rid of leading and trailing whitespace
-  */
-  trim: function(s) {
-    return s.replace(/^\s*|\s*$/g, '');
-  },
-};
+  });
+}();

test/mustache_spec.rb

@@ -8,18 +8,34 @@ testnames = Dir.glob(__DIR__ + '/../examples/*.js').map do |name|
 end
 
 describe "mustache" do
+  before(:all) do
+    @mustache = File.read(__DIR__ + "/../mustache.js")
+  end
+
+  it "should clear the context after each run" do
+    js = <<-JS
+      #{@mustache}
+      Mustache.to_html("{{#list}}{{x}}{{/list}}", {list: [{x: 1}]})
+      try {
+        print(Mustache.to_html("{{#list}}{{x}}{{/list}}", {list: [{}]}));
+      } catch(e) {
+        print('ERROR: ' + e);
+      }
+    JS
+    run_js(js).should == "ERROR: Can't find x in [object Object]\n"
+  end
+  
   testnames.each do |testname|
-    
     describe testname do
       it "should generate the correct html" do
         view = File.read(__DIR__ + "/../examples/#{testname}.js")
         template = File.read(__DIR__ + "/../examples/#{testname}.html").to_json
         expect = File.read(__DIR__ + "/../examples/#{testname}.txt")
-
-        mustache = File.read(__DIR__ + "/../mustache.js")
+  
+        
         runner = <<-JS
         try {
-          #{mustache}
+          #{@mustache}
           #{view}
           var template = #{template};
           var result = Mustache.to_html(template, #{testname});
@@ -28,13 +44,16 @@ describe "mustache" do
           print('ERROR: ' + e.message);
         }
         JS
-
-        File.open("runner.js", 'w') {|f| f << runner}
-
-        result = `js runner.js`
-        result.should == expect
+  
+        
+        run_js(runner).should == expect
       end
     end
   end
+  
+  def run_js(js)
+    File.open("runner.js", 'w') {|f| f << js}
+    `js runner.js`
+  end
 end