issue-1233: added grunt diff (#1235)

grunt/config/javascript.js

@@ -21,6 +21,12 @@ module.exports = function (grunt, options) {
                 generateSourceMaps: true,
                 preserveLicenseComments:false,
                 optimize: 'none'
+            },
+            //newer configuration
+            files: {
+              '<%= outputdir %>adapt/js/adapt.min.js': [
+                '<%= sourcedir %>/**/*.js'
+              ]
             }
         },
         compile: {

grunt/config/less.js

@@ -21,6 +21,12 @@ module.exports = function (grunt, options) {
                 filter: function(filepath) {
                     return grunt.config('helpers').includedFilter(filepath);
                 }
+            },
+            //newer configuration
+            files: {
+              '<%= outputdir %>adapt/css/adapt.css': [
+                '<%= sourcedir %>/**/*.less'
+              ]
             }
         },
         compile: {

grunt/tasks/diff.js

@@ -0,0 +1,17 @@
+/**
+* For development
+*/
+module.exports = function(grunt) {
+    grunt.registerTask('diff', 'Differential compile on a developer-friendly build of the course', [
+        '_log-vars',
+        'check-json',
+        'copy',
+        'newer:handlebars:compile',
+        'create-json-config',
+        'schema-defaults',
+        'tracking-insert',
+        'newer:javascript:dev',
+        'newer:less:dev',
+        'replace'
+    ]);
+}

package.json

@@ -143,6 +143,7 @@
     "grunt-contrib-watch": "~1.0.0",
     "grunt-jscs": "~2.8.0",
     "grunt-jsonlint": "~1.0.7",
+    "grunt-newer": "^1.2.0",
     "grunt-open": "~0.2.3",
     "grunt-replace": "~1.0.1",
     "jit-grunt": "~0.10.0",