Bind functions to the context properly.

The regression was introduced in 1.0.rc.1.

This fixes issue handlebars-lang#317.

lib/handlebars/compiler/compiler.js

@@ -642,7 +642,7 @@ Handlebars.JavaScriptCompiler = function() {};
       this.context.aliases.functionType = '"function"';
 
       this.replaceStack(function(current) {
-        return "typeof " + current + " === functionType ? " + current + "() : " + current;
+        return "typeof " + current + " === functionType ? " + current + ".apply(depth0) : " + current;
       });
     },
 
@@ -787,7 +787,7 @@ Handlebars.JavaScriptCompiler = function() {};
       var nextStack = this.nextStack();
 
       this.source.push('if (foundHelper) { ' + nextStack + ' = foundHelper.call(' + helper.callParams + '); }');
-      this.source.push('else { ' + nextStack + ' = ' + nonHelper + '; ' + nextStack + ' = typeof ' + nextStack + ' === functionType ? ' + nextStack + '() : ' + nextStack + '; }');
+      this.source.push('else { ' + nextStack + ' = ' + nonHelper + '; ' + nextStack + ' = typeof ' + nextStack + ' === functionType ? ' + nextStack + '.apply(depth0) : ' + nextStack + '; }');
     },
 
     // [invokePartial]

spec/qunit_spec.js

@@ -136,6 +136,8 @@ test("functions returning safestrings shouldn't be escaped", function() {
 test("functions", function() {
   shouldCompileTo("{{awesome}}", {awesome: function() { return "Awesome"; }}, "Awesome",
                   "functions are called and render their output");
+  shouldCompileTo("{{awesome}}", {awesome: function() { return this.more; }, more:  "More awesome"}, "More awesome",
+                  "functions are bound to the context");
 });
 
 test("paths with hyphens", function() {
@@ -616,6 +618,11 @@ test("Invert blocks work in knownHelpers only mode", function() {
   var result = template({foo: false});
   equal(result, "bar", "'bar' should === '" + result);
 });
+test("Functions are bound to the context in knownHelpers only mode", function() {
+  var template = CompilerContext.compile("{{foo}}", {knownHelpersOnly: true});
+  var result = template({foo: function() { return this.bar; }, bar: 'bar'});
+  equal(result, "bar", "'bar' should === '" + result);
+});
 
 suite("blockHelperMissing");
 
@@ -624,6 +631,11 @@ test("lambdas are resolved by blockHelperMissing, not handlebars proper", functi
   var data = { truthy: function() { return true; } };
   shouldCompileTo(string, data, "yep");
 });
+test("lambdas resolved by blockHelperMissing are bound to the context", function() {
+  var string = "{{#truthy}}yep{{/truthy}}";
+  var boundData = { truthy: function() { return this.truthiness(); }, truthiness: function() { return false; } };
+  shouldCompileTo(string, boundData, "");
+});
 
 var teardown;
 suite("built-in helpers", {