Gruntfile.js

module.exports = function(grunt) {
  'use strict';

  require('load-grunt-tasks')(grunt);
  require('time-grunt')(grunt);

  // config
    var concatBanner = '/*!\n' +
                       ' * Material\n' +
                       ' */\n' +
                       'if (typeof jQuery === \'undefined\') {\n' +
                       '  throw new Error(\'Material\\\'s JavaScript requires jQuery\')\n' +
                       '}\n\n' +
                       '+function ($) {\n' +
                       '  var version = $.fn.jquery.split(\' \')[0].split(\'.\')\n' +
                       '  if ((version[0] < 2 && version[1] < 9) || (version[0] == 1 && version[1] == 9 && version[2] < 1) || (version[0] >= 4)) {\n' +
                       '    throw new Error(\'Material\\\'s JavaScript requires at least jQuery v1.9.1 but less than v4.0.0\')\n' +
                       '  }\n' +
                       '}(jQuery);\n\n' +
                       '+function ($) {\n' +
                       '\'use strict\';\n\n';

    var concatFooter = '\n}(jQuery);';

    var postcssOptions = {
      browsers: [
        'Android 2.3',
        'Android >= 4',
        'Chrome >= 35',
        'Edge >= 12',
        'Explorer >= 10',
        'Firefox >= 38',
        'iOS >= 8',
        'Opera >= 12',
        'Safari >= 8'
      ]
    };

    var sassOptions = {
      precision: 6,
      sourcemap: 'auto',
      style:     'expanded',
      trace:     true
    };

  // project configuration
    grunt.initConfig({
      pkg: grunt.file.readJSON('package.json'),

      babel: {
        material: {
          options: {
            'babelrc': false,
            'plugins': [
              'transform-es2015-modules-strip'
            ],
            'presets': [
              'es2015'
            ]
          },
          dest: '<%= concat.babelpre.dest %>',
          src: '<%= concat.babelpre.dest %>'
        }
      },

      concat: {
        babelpost: {
          options: {
            banner: concatBanner,
            footer: concatFooter,
            process: function(file, filepath) {
              return file.replace(/(^|\n)[ \t]*('use strict'|"use strict");?\s*/g, '$1');
            },
            stripBanners: {
              block: false,
              line: true
            }
          },
          dest: '<%= babel.material.dest %>',
          src: '<%= babel.material.dest %>'
        },
        babelpre: {
          dest: 'assets/js/src.js',
          src: 'assets/js/src/**/*.js'
        },
        material: {
          dest: 'js/material.js',
          src: [
            'assets/js/addons/**/*.js',
            'assets/js/addons-materialise/**/*.js',
            '<%= concat.babelpost.dest %>',
          ]
        },
        project: {
          dest: 'js/project.js',
          src: 'assets/js-project/**/*.js'
        }
      },

      connect: {
        live: {
          options: {
            base: '',
            keepalive: true,
            hostname: '0.0.0.0',
            port: '9999'
          }
        },
        once: {
          options: {
            base: '',
            keepalive: false,
            hostname: '0.0.0.0',
            port: '9999'
          }
        }
      },

      cssmin: {
        material: {
          dest: 'css/material.min.css',
          src: '<%= postcss.material.dest %>'
        },
        project: {
          dest: 'css/project.min.css',
          src: '<%= postcss.project.dest %>'
        }
      },

      jekyll: {
        options: {
          bundleExec: true,
          config: '_config.yml',
          incremental: false
        },
        material: {}
      },

      postcss: {
        options: {
          map: false,
          processors: [
            require('autoprefixer') (postcssOptions)
          ]
        },

        material: {
          dest: 'css/material.css',
          src: '<%= sass.material.dest %>'
        },
        project: {
          dest: 'css/project.css',
          src: '<%= sass.project.dest %>'
        }
      },

      prettify: {
        options: {
          indent_inner_html: false
        },
        material: {
          cwd: 'gh-pages/',
          dest: 'gh-pages/',
          expand: true,
          ext: '.html',
          src: ['**/*.html']
        }
      },

      sass: {
        material: {
          options: sassOptions,

          dest: 'css/material.css',
          src: 'assets/sass/material.scss'
        },
        project: {
          options: sassOptions,

          dest: 'css/project.css',
          src: 'assets/sass-project/project.scss'
        }
      },

      uglify: {
        material: {
          dest: 'js/material.min.js',
          src: '<%= concat.material.dest %>'
        },
        project: {
          dest: 'js/project.min.js',
          src: '<%= concat.project.dest %>'
        }

      },

      watch: {
        default: {
          files: [
            'assets/**/*.js',
            'assets/**/*.scss'
          ],
          tasks: [
            'default'
          ]
        },
        material: {
          files: [
            'assets/js/**/*.js',
            'assets/sass/**/*.scss'
          ],
          tasks: [
            'material'
          ]
        },
        project: {
          files: [
            'assets/js-project/**/*.js',
            'assets/sass-project/**/*.scss'
          ],
          tasks: [
            'project'
          ]
        }
      },

      // update package.json packages
        devUpdate: {
          default: {
            options: {
              semver: false,
              updateType: 'prompt'
            }
          }
        }
    });

  // task registration
    grunt.registerTask(
      'default',
      [
        'material',
        'project'
      ]
    );

    grunt.registerTask(
      'doc',
      [
        'jekyll:material',
        'prettify:material'
      ]
    );

    grunt.registerTask(
      'material',
      [
        'material-css',
        'material-js'
      ]
    );

    grunt.registerTask(
      'material-css',
      [
        'sass:material',
        'postcss:material',
        'cssmin:material'
      ]
    );

    grunt.registerTask(
      'material-js',
      [
        'concat:babelpre',
        'babel:material',
        'concat:babelpost',
        'concat:material',
        'uglify:material'
      ]
    );

    grunt.registerTask(
      'project',
      [
        'project-css',
        'project-js'
      ]
    );

    grunt.registerTask(
      'project-css',
      [
        'sass:project',
        'postcss:project',
        'cssmin:project'
      ]
    );

    grunt.registerTask(
      'project-js',
      [
        'concat:project',
        'uglify:project'
      ]
    );
};