Added bodyclass and postclass helper

closes #472

- filterable as array, output as string
- with unit tests

core/server/helpers/index.js

@@ -89,6 +89,32 @@ coreHelpers = function (ghost) {
         );
     });
 
+
+    ghost.registerThemeHelper('bodyclass', function (options) {
+        var classes = [];
+        if (!this.path || this.path === '/' || this.path === '') {
+            classes.push('home');
+        } else {
+            classes.push('post');
+        }
+
+        return ghost.doFilter('bodyclass', classes, function (classes) {
+            var classString = _.reduce(classes, function (memo, item) { return memo + ' ' + item; }, '');
+            return new hbs.handlebars.SafeString(classString.trim());
+        });
+    });
+
+    ghost.registerThemeHelper('postclass', function (options) {
+        var classes = ['post'];
+
+        // TODO: add tag names once we have them
+        return ghost.doFilter('postclass', classes, function (classes) {
+            var classString = _.reduce(classes, function (memo, item) { return memo + ' ' + item; }, '');
+            return new hbs.handlebars.SafeString(classString.trim());
+        });
+    });
+
+
     /**
      * [ description]
      *

core/test/unit/frontend_helpers_index_spec.js

@@ -116,8 +116,43 @@ describe('Core Helpers', function () {
             should.exist(rendered);
             rendered.string.should.equal(expected);
         });
+    });
 
+    describe('Bodyclass Helper', function () {
+        it('has loaded bodyclass helper', function () {
+            should.exist(handlebars.helpers.bodyclass);
+        });
 
+        it('can render class string', function () {
+            var rendered = handlebars.helpers.bodyclass.call({});
+            should.exist(rendered);
+
+            rendered.string.should.equal('home');
+        });
+
+        it('can render class string for context', function () {
+            var rendered1 = handlebars.helpers.bodyclass.call({path: '/'}),
+                rendered2 = handlebars.helpers.bodyclass.call({path: '/a-post-title'});
+
+            should.exist(rendered1);
+            should.exist(rendered2);
+
+            rendered1.string.should.equal('home');
+            rendered2.string.should.equal('post');
+        });
+    });
+
+    describe('Postclass Helper', function () {
+        it('has loaded postclass helper', function () {
+            should.exist(handlebars.helpers.postclass);
+        });
+
+        it('can render class string', function () {
+            var rendered = handlebars.helpers.postclass.call({});
+            should.exist(rendered);
+
+            rendered.string.should.equal('post');
+        });
     });
 
     describe('Navigation Helper', function () {