Add decorator parsing

lib/handlebars/compiler/helpers.js

@@ -84,8 +84,9 @@ export function prepareMustache(path, params, hash, open, strip, locInfo) {
   let escapeFlag = open.charAt(3) || open.charAt(2),
       escaped = escapeFlag !== '{' && escapeFlag !== '&';
 
+  let decorator = (/\*/.test(open));
   return {
-    type: 'MustacheStatement',
+    type: decorator ? 'Decorator' : 'MustacheStatement',
     path,
     params,
     hash,
@@ -124,12 +125,18 @@ export function prepareBlock(openBlock, program, inverseAndProgram, close, inver
     validateClose(openBlock, close);
   }
 
+  let decorator = (/\*/.test(openBlock.open));
+
   program.blockParams = openBlock.blockParams;
 
   let inverse,
       inverseStrip;
 
   if (inverseAndProgram) {
+    if (decorator) {
+      throw new Exception('Unexpected inverse block on decorator', inverseAndProgram);
+    }
+
     if (inverseAndProgram.chain) {
       inverseAndProgram.program.body[0].closeStrip = close.strip;
     }
@@ -145,7 +152,7 @@ export function prepareBlock(openBlock, program, inverseAndProgram, close, inver
   }
 
   return {
-    type: 'BlockStatement',
+    type: decorator ? 'DecoratorBlock' : 'BlockStatement',
     path: openBlock.path,
     params: openBlock.params,
     hash: openBlock.hash,

lib/handlebars/compiler/printer.js

@@ -48,11 +48,15 @@ PrintVisitor.prototype.Program = function(program) {
 PrintVisitor.prototype.MustacheStatement = function(mustache) {
   return this.pad('{{ ' + this.SubExpression(mustache) + ' }}');
 };
+PrintVisitor.prototype.Decorator = function(mustache) {
+  return this.pad('{{ DIRECTIVE ' + this.SubExpression(mustache) + ' }}');
+};
 
-PrintVisitor.prototype.BlockStatement = function(block) {
+PrintVisitor.prototype.BlockStatement =
+PrintVisitor.prototype.DecoratorBlock = function(block) {
   let out = '';
 
-  out += this.pad('BLOCK:');
+  out += this.pad((block.type === 'DecoratorBlock' ? 'DIRECTIVE ' : '') + 'BLOCK:');
   this.padding++;
   out += this.pad(this.SubExpression(block));
   if (block.program) {

lib/handlebars/compiler/visitor.js

@@ -76,8 +76,10 @@ Visitor.prototype = {
   },
 
   MustacheStatement: visitSubExpression,
+  Decorator: visitSubExpression,
 
   BlockStatement: visitBlock,
+  DecoratorBlock: visitBlock,
 
   PartialStatement: visitPartial,
   PartialBlockStatement: function(partial) {

lib/handlebars/compiler/whitespace-control.js

@@ -63,6 +63,7 @@ WhitespaceControl.prototype.Program = function(program) {
 };
 
 WhitespaceControl.prototype.BlockStatement =
+WhitespaceControl.prototype.DecoratorBlock =
 WhitespaceControl.prototype.PartialBlockStatement = function(block) {
   this.accept(block.program);
   this.accept(block.inverse);
@@ -124,6 +125,7 @@ WhitespaceControl.prototype.PartialBlockStatement = function(block) {
   return strip;
 };
 
+WhitespaceControl.prototype.Decorator =
 WhitespaceControl.prototype.MustacheStatement = function(mustache) {
   return mustache.strip;
 };