Here is how I did it with Wamp 2.2 on Windows 7.
First, you need grunt-contrib-watch properly setup with livereload. I also use grunt-sass and not grunt-contrib-sass, because grunt-sass use Libsass. LibSass is a C/C++ port of the Sass engine, and it is faster.
To install them, use these commands :
npm install grunt-contrib-watch --save-dev
npm install grunt-sass --save-dev
Here is an example of Gruntfile :
module.exports = function(grunt) {
grunt.initConfig({
watch: {
sass: {
files: 'folder/to/your/sass/**/*.sass',
tasks: ['sass:dist'],
options: {
livereload: true,
},
},
//Watch your theme files
livereload: {
files: ['pathToTheme/*.php', 'pathToTheme/img/**/*.{png,jpg,jpeg,gif,webp,svg}'],
options: {
livereload: true
},
}
},
sass: {
options: {
includePaths: ['where/to/find/additional/@import/scss/files'],
outputStyle: 'nested',
imagePath: 'how/to/rewrite/image/path',
sourceMap: true
},
dist: {
files: {
'output/file.css': 'input/file.scss'
}
}
},
});
// Default task
grunt.registerTask('default', ['watch']);
// Load NpmTask
grunt.loadNpmTasks('grunt-contrib-watch');
grunt.loadNpmTasks('grunt-sass');
};
You could save yourself some time with load-grunt-tasks, and remove the manual loading of task :
require('load-grunt-tasks')(grunt); // npm install --save-dev load-grunt-tasks
Then I use the livereload plugin for firefox (or chrome or safari).
Start the grunt watch task, open your site on localhost, and click on the icon in your browser. Now if you edit a watched file, the page should update accordingly.
A solution exist to add the livereload js in your Wordpress automatically (in function.php):
if (in_array($_SERVER['REMOTE_ADDR'], array('127.0.0.1', '::1'))) {
wp_register_script('livereload', 'http://localhost:35729/livereload.js?snipver=1', null, false, true);
wp_enqueue_script('livereload');
}