Incremental JSHint and LintSpaces checking

gistfile1.js

var JAVASCRIPT_FILES = ['lib/**/*.js', 'routes/**/*.js', 'public/js/**/*.js'];

grunt.initConfig({
  jshint: {
    options: {
      reporter: require('jshint-stylish'),
      force: true,
      /* https://github.com/gruntjs/grunt-contrib-jshint
         http://jshint.com/docs/options/ */
    },
    all: {
      src: JAVASCRIPT_FILES
    },
    changed: {
      src: JAVASCRIPT_FILES,
      filter: function(filePath) {
        return grunt.config.get('git.changed').indexOf( filePath ) != -1;
      }
    }
  },
  lintspaces: {
    all: {
      src: JAVASCRIPT_FILES
    },
    changed: {
      src: JAVASCRIPT_FILES,
      filter: function(filePath) {
        return grunt.config.get('git.changed').indexOf( filePath ) != -1;
      }
    },
    options: {
      /* https://www.npmjs.com/package/grunt-lintspaces */
      indentation: 'spaces',
      spaces: 2,
      ignores: [ 'js-comments' ]
    }
  }
});

grunt.loadNpmTasks('grunt-contrib-jshint');
grunt.loadNpmTasks('grunt-lintspaces');
grunt.loadNpmTasks('grunt-git-changedfiles');

grunt.registerTask('check', ['git_changedfiles', 'jshint:changed', 'lintspaces:changed']);