Added basic nested context lookups and context stack.

lib/handlebars.js

@@ -2,7 +2,7 @@ Handlebars = {
   compile: function(string) {
     var compiler = new Handlebars.Compiler(string);
     var result   = compiler.compile();
-    return new Function("context", "fallback", "fallback = fallback || {}; " + result);
+    return new Function("context", "fallback", "fallback = fallback || {}; stack = [];" + result);
   },
 
   isFunction: function(fn) {
@@ -84,7 +84,19 @@ Handlebars.Compiler.prototype = {
   },
 
   lookupFor: function(param) {
-    return param ? "( context['" + param + "'] || fallback['" + param + "'] )" : "context";
+    if (!param) {
+      return "context";
+    }
+
+    var parts = param.split("../");
+    param = parts[parts.length - 1];
+    depth = parts.length - 1;
+
+    if (depth > 0) {
+      return "( stack[stack.length - " + depth + "]['" + param + "'] )";
+    } else {
+      return "( context['" + param + "'] || fallback['" + param + "'] )";
+    }
   },
 
   parseMustache: function() {
@@ -133,9 +145,11 @@ Handlebars.Compiler.prototype = {
           var fnId = "fn" + this.pointer.toString();
 
           this.fn += "var " + fnId + " = function(context) {" + result + "}; ";
+          this.fn += "stack.push(context);"
           this.fn += "lookup = " + this.lookupFor(mustache) + "; ";
           this.fn += "if(Handlebars.isFunction(lookup)) out = out + lookup.call(" + param + ", " + fnId + "); "
           this.fn += "else if(typeof lookup !== 'undefined') out = out + Handlebars.helperMissing.call(" + param + ", lookup, " + fnId + "); "
+          this.fn += "stack.pop(context);"
 
           this.openBlock = false;
           return;

test/handlebars.js

@@ -42,6 +42,13 @@ test("nested iteration", function() {
 
 });
 
+test("block with complex lookup", function() {
+  var string = "{{#goodbyes}}{{text}} cruel {{../name}}! {{/goodbyes}}"
+  var hash     = {name: "Alan", goodbyes: [{text: "goodbye"}, {text: "Goodbye"}, {text: "GOODBYE"}]};
+
+  shouldCompileTo(string, hash, "goodbye cruel Alan! Goodbye cruel Alan! GOODBYE cruel Alan! ");
+});
+
 test("block helper", function() {
   var string   = "{{#goodbyes}}{{text}}! {{/goodbyes}}cruel {{world}}!";
   var template = Handlebars.compile(string);