Convert children to nested functions. Reuse identifiers by closure where possible.

2 files changed, 53 insertions, 82 deletions

diff --git a/lib/handlebars/compiler/compiler.js b/lib/handlebars/compiler/compiler.js
index 3a48c16..4a60c05 100644
--- a/lib/handlebars/compiler/compiler.js
+++ b/lib/handlebars/compiler/compiler.js
@@ -315,12 +315,14 @@ Handlebars.JavaScriptCompiler = function() {};
     },
     // END PUBLIC API
 
-    compile: function(environment, options, asObject) {
+    compile: function(environment, options, context, asObject) {
       this.environment = environment;
       this.options = options || {};
 
-      this.context = {
-        aliases: {},
+      this.name = this.environment.name;
+      this.isChild = !!context;
+      this.context = context || {
+        programs: [],
         aliases: { self: 'this' },
         registers: {list: []}
       };
@@ -330,7 +332,7 @@ Handlebars.JavaScriptCompiler = function() {};
       this.stackSlot = 0;
       this.stackVars = [];
 
-      this.compileChildren(environment, options, asObject);
+      this.compileChildren(environment, options);
 
       var opcodes = environment.opcodes, opcode, name, declareName, declareVal;
 
@@ -380,9 +382,13 @@ Handlebars.JavaScriptCompiler = function() {};
     preamble: function() {
       var out = [];
 
-      var copies = "helpers = helpers || Handlebars.helpers;";
-      if(this.environment.usePartial) { copies = copies + " partials = partials || Handlebars.partials;"; }
-      out.push(copies);
+      if (!this.isChild) {
+        var copies = "helpers = helpers || Handlebars.helpers;";
+        if(this.environment.usePartial) { copies = copies + " partials = partials || Handlebars.partials;"; }
+        out.push(copies);
+      } else {
+        out.push('');
+      }
 
       out.push("var buffer = " + this.initializeBuffer() + ", currentContext = context");
 
@@ -393,25 +399,33 @@ Handlebars.JavaScriptCompiler = function() {};
     },
 
     createFunctionContext: function(asObject) {
-      var locals = this.stackVars.concat(this.context.registers.list);
+      var locals = this.stackVars;
+      if (!this.isChild) {
+        locals = locals.concat(this.context.registers.list);
+      }
 
       if(locals.length > 0) {
         this.source[1] = this.source[1] + ", " + locals.join(", ");
       }
 
       // Generate minimizer alias mappings
-      var aliases = []
-      for (var alias in this.context.aliases) {
-        this.source[1] = this.source[1] + ', ' + alias + '=' + this.context.aliases[alias];
+      if (!this.isChild) {
+        var aliases = []
+        for (var alias in this.context.aliases) {
+          this.source[1] = this.source[1] + ', ' + alias + '=' + this.context.aliases[alias];
+        }
       }
 
       this.source[1] = this.source[1] + ";";
 
-      this.source.push("return buffer;");
+      // Merge children
+      if (!this.isChild) {
+        this.source[1] += '\n' + this.context.programs.join('\n') + '\n';
+      }
 
-      var params = ["Handlebars", "context", "helpers", "partials"];
+      this.source.push("return buffer;");
 
-      if(this.options.data) { params.push("data"); }
+      var params = this.isChild ? ["context", "data"] : ["Handlebars", "context", "helpers", "partials", "data"];
 
       for(var i=0, l=this.environment.depths.list.length; i<l; i++) {
         params.push("depth" + this.environment.depths.list[i]);
@@ -422,24 +436,11 @@ Handlebars.JavaScriptCompiler = function() {};
       if (asObject) {
         params.push(this.source.join("\n  "));
 
-        return {
-          fn: Function.apply(this, params),
-          children: this.environment.children
-        };
+        return Function.apply(this, params);
       } else {
-        var functionSource = 'function(' + params.join(',') + ') {\n  ' + this.source.join("\n  ") + '}';
-
+        var functionSource = 'function ' + (this.name || '') + '(' + params.join(',') + ') {\n  ' + this.source.join("\n  ") + '}';
         Handlebars.log(Handlebars.logger.DEBUG, functionSource + "\n\n");
-
-        var script = ['{\n  fn: ', functionSource, ',\n  children: [\n    '],
-            children = this.environment.children;
-        for (var i = 0, len = children.length; i < len; i++) {
-          script.push(children[i]);
-          if (i < len-1) { script.push(',\n'); }
-        }
-        script.push('\n  ]\n}');
-
-        return script.join('');
+        return functionSource;
       }
     },
 
@@ -582,7 +583,7 @@ Handlebars.JavaScriptCompiler = function() {};
     },
 
     invokePartial: function(context) {
-      this.pushStack("this.invokePartial(" + this.nameLookup('partials', context, 'partial') + ", '" + context + "', " + this.popStack() + ", helpers, partials);");
+      this.pushStack("self.invokePartial(" + this.nameLookup('partials', context, 'partial') + ", '" + context + "', " + this.popStack() + ", helpers, partials);");
     },
 
     assignToHash: function(key) {
@@ -596,29 +597,27 @@ Handlebars.JavaScriptCompiler = function() {};
 
     compiler: JavaScriptCompiler,
 
-    compileChildren: function(environment, options, asObject) {
+    compileChildren: function(environment, options) {
       var children = environment.children, child, compiler;
-      var compiled = [];
 
       for(var i=0, l=children.length; i<l; i++) {
         child = children[i];
         compiler = new this.compiler();
 
-        compiled[i] = compiler.compile(child, options, asObject);
+        this.context.programs.push('');     // Placeholder to prevent name conflicts for nested children
+        var index = this.context.programs.length;
+        child.index = index;
+        child.name = 'program' + index;
+        this.context.programs[index] = compiler.compile(child, options, this.context);
       }
-
-      environment.rawChildren = children;
-      environment.children = compiled;
     },
 
     programExpression: function(guid) {
-
-      var programParams = [guid, "helpers", "partials"];
       if(guid == null) { return "self.noop"; }
 
-      var depths = this.environment.rawChildren[guid].depths.list;
-
-      if(this.options.data) { programParams.push("data"); }
+      var child = this.environment.children[guid],
+          depths = child.depths.list;
+      var programParams = [child.index, child.name, "data"];
 
       for(var i=0, l = depths.length; i<l; i++) {
         depth = depths[i];
@@ -627,18 +626,10 @@ Handlebars.JavaScriptCompiler = function() {};
         else { programParams.push("depth" + (depth - 1)); }
       }
 
-      if(!this.environment.usePartial) {
-        if(programParams[3]) {
-          programParams[2] = "null";
-        } else {
-          programParams.pop();
-        }
-      }
-
       if(depths.length === 0) {
         return "self.program(" + programParams.join(", ") + ")";
       } else {
-        programParams[0] = "this.children[" + guid + "]";
+        programParams.shift();
         return "self.programWithDepth(" + programParams.join(", ") + ")";
       }
     },
@@ -704,7 +695,7 @@ Handlebars.precompile = function(string, options) {
 Handlebars.compile = function(string, options) {
   var ast = Handlebars.parse(string);
   var environment = new Handlebars.Compiler().compile(ast, options);
-  var templateSpec = new Handlebars.JavaScriptCompiler().compile(environment, options, true);
+  var templateSpec = new Handlebars.JavaScriptCompiler().compile(environment, options, undefined, true);
   return Handlebars.template(templateSpec);
 };
 
diff --git a/lib/handlebars/vm.js b/lib/handlebars/vm.js
index 1930edc..7f9a42e 100644
--- a/lib/handlebars/vm.js
+++ b/lib/handlebars/vm.js
@@ -3,66 +3,46 @@ var Handlebars = require("./base");
 // BEGIN(BROWSER)
 Handlebars.VM = {
   template: function(templateSpec) {
-    // Setup all children
-    for (var i = 0, len = templateSpec.children.length; i < len; i++) {
-      templateSpec.children[i] = Handlebars.VM.template(templateSpec.children[i]);
-    }
-
     // Just add water
     var container = {
       escapeExpression: Handlebars.Utils.escapeExpression,
       invokePartial: Handlebars.VM.invokePartial,
       programs: [],
-      program: function(i, helpers, partials, data) {
+      program: function(i, fn, data) {
         var programWrapper = this.programs[i];
         if(data) {
-          return Handlebars.VM.program(this.children[i], helpers, partials, data);
+          return Handlebars.VM.program(fn, data);
         } else if(programWrapper) {
           return programWrapper;
         } else {
-          programWrapper = this.programs[i] = Handlebars.VM.program(this.children[i], helpers, partials);
+          programWrapper = this.programs[i] = Handlebars.VM.program(fn);
           return programWrapper;
         }
       },
       programWithDepth: Handlebars.VM.programWithDepth,
       noop: Handlebars.VM.noop
     };
-    container.render = templateSpec.fn;
-    container.children = templateSpec.children;
 
-    return function(context, options, $depth) {
+    return function(context, options) {
       options = options || {};
-      var args = [Handlebars, context, options.helpers, options.partials, options.data];
-      var depth = Array.prototype.slice.call(arguments, 2);
-      args = args.concat(depth);
-      return container.render.apply(container, args);
+      return templateSpec.call(container, Handlebars, context, options.helpers, options.partials, options.data);
     };
   },
 
-  programWithDepth: function(fn, helpers, partials, data, $depth) {
-    var args = Array.prototype.slice.call(arguments, 4);
+  programWithDepth: function(fn, data, $depth) {
+    var args = Array.prototype.slice.call(arguments, 2);
 
     return function(context, options) {
       options = options || {};
 
-      options = {
-        helpers: options.helpers || helpers,
-        partials: options.partials || partials,
-        data: options.data || data
-      };
-
-      return fn.apply(this, [context, options].concat(args));
+      return fn.apply(this, [context, options.data || data].concat(args));
     };
   },
-  program: function(fn, helpers, partials, data) {
+  program: function(fn, data) {
     return function(context, options) {
       options = options || {};
 
-      return fn(context, {
-        helpers: options.helpers || helpers,
-        partials: options.partials || partials,
-        data: options.data || data
-      });
+      return fn(context, options.data || data);
     };
   },
   noop: function() { return ""; },