Gruntfile.js

module.exports = function(grunt) {
    "use strict";
    grunt.loadNpmTasks("grunt-sync");
    grunt.loadNpmTasks("grunt-contrib-watch");
    grunt.loadNpmTasks("grunt-contrib-copy");
    grunt.loadNpmTasks("grunt-contrib-clean");
    grunt.loadNpmTasks("grunt-ts");
    grunt.loadNpmTasks("grunt-sass");
    grunt.loadNpmTasks('intern');

    var appDir =
        "C:/arcgis-web-appbuilder/arcgis-web-appbuilder-2.7/WebAppBuilderForArcGIS/server/apps/6";
    var stemappDir =
        "C:/arcgis-web-appbuilder/arcgis-web-appbuilder-2.7/WebAppBuilderForArcGIS/client/stemapp";

    grunt.initConfig({
        sync: {
            main: {
                verbose: true,
                files: [
                    {
                        cwd: "dist/",
                        src: "**",
                        dest: stemappDir
                    },
                    {
                        cwd: "dist/",
                        src: "**",
                        dest: appDir
                    }
                ]
            }
        },
        ts: {
            default: {
                tsconfig: {
                    passThrough : true
                }
            }
        },
        watch: {
            main: {
                files: ["widgets/**", "themes/**"],
                tasks: ["clean", "sass", "ts", "copy", "sync"],
                options: {
                    spawn: false,
                    atBegin: true
                }
            }
        },
        copy: {
            main: {
                src: [
                    "widgets/**/**.html",
                    "widgets/**/**.json",
                    "widgets/**/**.css",
                    "widgets/**/images/**",
                    "widgets/**/nls/**",
                    "themes/**/**.html",
                    "themes/**/**.json",
                    "themes/**/**.css",
                    "themes/**/images/**",
                    "themes/**/nls/**"
                ],
                dest: "dist/",
                expand: true
            }
        },
        clean: { dist: { src: "dist/**" } },
        sass: {
            dist: {
                options: { sourceMap: true },
                files: [
                    {
                        expand: true,
                        src: ["widgets/**/*.scss"],
                        rename: function(dest, src) {
                            return src.replace("scss", "css");
                        }
                    }
                ]
            }
        }
    });
    grunt.registerTask("default", ["watch"]);
};