Implement livereload into the watch task. Ref gruntjs/grunt-contrib-livereload#32

package.json

@@ -28,7 +28,8 @@
     "test": "grunt nodeunit -v"
   },
   "dependencies": {
-    "gaze": "~0.3.3"
+    "gaze": "~0.3.3",
+    "tiny-lr": "0.0.4"
   },
   "devDependencies": {
     "grunt": "~0.4.0",

tasks/lib/livereload.js

@@ -0,0 +1,37 @@
+/*
+ * grunt-contrib-watch
+ * http://gruntjs.com/
+ *
+ * Copyright (c) 2013 "Cowboy" Ben Alman, contributors
+ * Licensed under the MIT license.
+ */
+
+'use strict';
+
+var tinylr = require('tiny-lr');
+
+module.exports = function(grunt) {
+
+  var defaults = {
+    port: 35729
+  };
+
+  function LR(options) {
+    if (options === true) { options = defaults; }
+    else { options = grunt.util._.defaults(options, defaults); }
+    this.server = tinylr();
+    this.server.listen(options.port, function(err) {
+      if (err) { return grunt.fatal(err); }
+      grunt.log.verbose.writeln('Live reload server started on port: ' + options.port);
+    });
+  }
+
+  LR.prototype.trigger = function(files) {
+    grunt.log.verbose.writeln('Live reloading ' + grunt.log.wordlist(files) + '...');
+    this.server.changed({body:{files:files}});
+  };
+
+  return function(options) {
+    return new LR(options);
+  };
+};

tasks/lib/taskrun.js

@@ -14,6 +14,8 @@ var util = require('util');
 
 module.exports = function(grunt) {
 
+  var livereload = require('./livereload')(grunt);
+
   // Create a TaskRun on a target
   function TaskRun(target, defaults) {
     this.name = target.name || 0;
@@ -22,6 +24,12 @@ module.exports = function(grunt) {
     this.options = target.options;
     this.startedAt = false;
     this.spawned = null;
+    this.changedFiles = Object.create(null);
+
+    // If livereload is requested
+    if (this.options.livereload !== false) {
+      this.livereload = livereload(this.options.livereload);
+    }
   }
 
   // Run it
@@ -54,7 +62,7 @@ module.exports = function(grunt) {
     }
   };
 
-  // When the task has completed
+  // When the task run has completed
   TaskRun.prototype.complete = function() {
     var time = Date.now() - this.startedAt;
     this.startedAt = false;
@@ -62,6 +70,10 @@ module.exports = function(grunt) {
       this.spawned.kill('SIGINT');
       this.spawned = null;
     }
+    // Trigger livereload if set
+    if (this.livereload) {
+      this.livereload.trigger(Object.keys(this.changedFiles));
+    }
     return time;
   };
 

tasks/lib/taskrunner.js

@@ -39,6 +39,8 @@ module.exports = function(grunt) {
     this.reload = false;
     // For re-queuing arguments with the task that originally ran this
     this.nameArgs = [];
+    // A list of changed files to feed to task runs for livereload
+    this.changedFiles = Object.create(null);
   }
   util.inherits(Runner, EE);
 
@@ -148,6 +150,7 @@ module.exports = function(grunt) {
       var tr = self._targets[name];
       if (!tr) { return next(); }
       if (tr.options.nospawn) { shouldComplete = false; }
+      tr.changedFiles = self.changedFiles;
       tr.run(next);
     }, function() {
       if (shouldComplete) {
@@ -195,6 +198,7 @@ module.exports = function(grunt) {
       }
     });
     var elapsed = (time > 0) ? Number(time / 1000) : 0;
+    self.changedFiles = Object.create(null);
     self.emit('end', elapsed);
   };
 

tasks/watch.js

@@ -23,6 +23,7 @@ module.exports = function(grunt) {
       // Log which file has changed, and how.
       grunt.log.ok('File "' + filepath + '" ' + changedFiles[filepath] + '.');
     });
+    taskrun.changedFiles = changedFiles;
     // Reset changedFiles
     changedFiles = Object.create(null);
   });
@@ -68,6 +69,7 @@ module.exports = function(grunt) {
       nospawn: false,
       event: ['all'],
       target: target,
+      livereload: false,
     });
 
     targets.forEach(function(target, i) {

test/fixtures/livereload/Gruntfile.js

@@ -0,0 +1,39 @@
+module.exports = function(grunt) {
+  'use strict';
+
+  grunt.initConfig({
+    watch: {
+      basic: {
+        files: ['lib/*.js'],
+        tasks: ['before'],
+        options: {
+          livereload: true,
+        },
+      },
+      customport: {
+        files: ['lib/*.js'],
+        tasks: ['before'],
+        options: {
+          livereload: {
+            port: 8675,
+          },
+        },
+      },
+      nospawn: {
+        files: ['lib/*.js'],
+        tasks: ['before'],
+        options: {
+          nospawn: true,
+          livereload: true,
+        },
+      },
+    },
+  });
+
+  // Load this watch task
+  grunt.loadTasks('../../../tasks');
+
+  grunt.registerTask('before', function() {
+    grunt.log.writeln('I ran before livereload.');
+  });
+};

test/fixtures/livereload/lib/one.js

@@ -0,0 +1 @@
+var one = true;

test/tasks/livereload_test.js

@@ -0,0 +1,105 @@
+'use strict';
+
+var grunt = require('grunt');
+var path = require('path');
+var fs = require('fs');
+var http = require('http');
+var helper = require('./helper');
+
+var fixtures = helper.fixtures;
+
+function cleanUp() {
+  helper.cleanUp([
+    'livereload/node_modules',
+  ]);
+}
+
+// Helper for requesting the live reload server
+function request(port, done) {
+  var data = '';
+  var req = http.request({
+    hostname: 'localhost',
+    port: port,
+  }, function(res) {
+    res.setEncoding('utf8');
+    res.on('data', function(chunk) {
+      data += chunk;
+    });
+    res.on('end', function() {
+      done(data);
+    });
+  });
+  req.end();
+}
+
+exports.livereload = {
+  setUp: function(done) {
+    cleanUp();
+    fs.symlinkSync(path.join(__dirname, '../../node_modules'), path.join(fixtures, 'livereload', 'node_modules'));
+    done();
+  },
+  tearDown: function(done) {
+    cleanUp();
+    done();
+  },
+  basic: function(test) {
+    test.expect(4);
+    var resultData = '';
+    var cwd = path.resolve(fixtures, 'livereload');
+    var assertWatch = helper.assertTask(['watch:basic', '-v'], {cwd: cwd});
+    assertWatch([function() {
+      request(35729, function(data) {
+        resultData += data;
+        grunt.file.write(path.join(cwd, 'lib', 'one.js'), 'var one = true;');
+      });
+    }], function(result) {
+      helper.verboseLog(result);
+      test.ok(result.indexOf('I ran before livereload.') !== -1, 'task should have ran before live reload.');
+      test.ok(result.indexOf('Live reload server started on port: 35729') !== -1, 'live reload server should have been started on port 35729.');
+      test.ok(result.indexOf('Live reloading lib/one.js...') !== -1, 'live reload should have triggered on lib/one.js');
+      resultData = JSON.parse(resultData);
+      test.equal(resultData.tinylr, 'Welcome', 'tinylr server should have welcomed you.');
+      test.done();
+    });
+  },
+  customport: function(test) {
+    test.expect(4);
+    var resultData = '';
+    var cwd = path.resolve(fixtures, 'livereload');
+    var assertWatch = helper.assertTask(['watch:customport', '-v'], {cwd: cwd});
+    assertWatch([function() {
+      request(8675, function(data) {
+        resultData += data;
+        grunt.file.write(path.join(cwd, 'lib', 'one.js'), 'var one = true;');
+      });
+    }], function(result) {
+      helper.verboseLog(result);
+      test.ok(result.indexOf('I ran before livereload.') !== -1, 'task should have ran before live reload.');
+      test.ok(result.indexOf('Live reload server started on port: 8675') !== -1, 'live reload server should have been started on port 35729.');
+      test.ok(result.indexOf('Live reloading lib/one.js...') !== -1, 'live reload should have triggered on lib/one.js');
+      resultData = JSON.parse(resultData);
+      test.equal(resultData.tinylr, 'Welcome', 'tinylr server should have welcomed you.');
+      test.done();
+    });
+  },
+  nospawn: function(test) {
+    test.expect(4);
+    var resultData = '';
+    var cwd = path.resolve(fixtures, 'livereload');
+    var assertWatch = helper.assertTask(['watch:nospawn', '-v'], {cwd: cwd});
+    assertWatch([function() {
+      request(35729, function(data) {
+        resultData += data;
+        grunt.file.write(path.join(cwd, 'lib', 'one.js'), 'var one = true;');
+      });
+    }], function(result) {
+      helper.verboseLog(result);
+      test.ok(result.indexOf('I ran before livereload.') !== -1, 'task should have ran before live reload.');
+      test.ok(result.indexOf('Live reload server started on port: 35729') !== -1, 'live reload server should have been started on port 35729.');
+      test.ok(result.indexOf('Live reloading lib/one.js...') !== -1, 'live reload should have triggered on lib/one.js');
+      resultData = JSON.parse(resultData);
+      test.equal(resultData.tinylr, 'Welcome', 'tinylr server should have welcomed you.');
+      test.done();
+    });
+  },
+};