chore(build): watch logger should honor ignoreInitial option

It was confusing because the test.unit.dart task does ignore the initial, and
the logger was hardcoded to always ignore the first task, leading to the appearance
that a run was happening twice for no reason.

Also, fixed the "fake ignoreInitial" handling to not rely on a fake event, which
is not necessary.

Closes #2101

gulpfile.js

@@ -335,10 +335,7 @@ function createDocsTasks(publicBuild) {
 
   gulp.task(taskPrefix, [taskPrefix + '/assets', taskPrefix + '/app', taskPrefix + '/dgeni']);
   gulp.task(taskPrefix + '/watch', function() {
-    return watch('docs/app/**/*', {
+    return watch('docs/app/**/*', [taskPrefix + '/app']);
-      ignoreInitial: false,
-      log: watchLog
-    }, [taskPrefix + '/app']);
   });
 
   gulp.task(taskPrefix + '/test', function (done) {
@@ -439,7 +436,7 @@ gulp.task('test.unit.dart', function (done) {
         return;
       }
 
-      watch('modules/angular2/**', { ignoreInitial: true, log: watchLog }, [
+      watch('modules/angular2/**', { ignoreInitial: true }, [
         '!build/tree.dart',
         '!test.unit.dart/karma-run'
       ]);
@@ -488,7 +485,7 @@ gulp.task('test.unit.cjs', ['build/clean.js', 'build.tools'], function (neverDon
     'test.unit.cjs/ci'
   ];
 
-  watch('modules/**', { ignoreInitial: false, log: watchLog }, buildAndTest);
+  watch('modules/**', buildAndTest);
 });
 
 
@@ -506,10 +503,7 @@ gulp.task('test.unit.tools', ['build/clean.tools'],  function(done) {
     'test.unit.tools/ci'
   ];
 
-  watch(['tools/**', '!tools/**/test-fixtures/**'], {
+  watch(['tools/**', '!tools/**/test-fixtures/**'], buildAndTest);
-    ignoreInitial: false,
-    log: watchLog
-  }, buildAndTest);
 });
 
 
@@ -895,21 +889,3 @@ process.on('beforeExit', function() {
   beforeExitRan = true;
   gulp.start('cleanup.builder');
 });
-
-function watchLog(triggerCount) {
-  // Ignore initial event
-  if (!--triggerCount) return;
-
-  process.stdout.write([
-    '',
-    '==================================================',
-    ' WATCH TRIGGERED BY FILE CHANGE #' + triggerCount,
-    ' On: ' + prettyTime(),
-    '==================================================\n',
-  ].join('\n'));
-
-  function prettyTime() {
-    var now = new Date();
-    return now.toLocaleDateString() + " at " + now.toLocaleTimeString();
-  }
-}

tools/build/watch.js

@@ -12,8 +12,6 @@ function watch(globs, opts, tasks) {
   var useRunSequence = typeof tasks !== 'function';
   var runTasks;
 
-  var log = typeof opts.log === 'function' ? opts.log : function noop() {};
-
   if (useRunSequence) {
     if (!Array.isArray(tasks)) tasks = [tasks];
     tasks = tasks.slice();
@@ -50,6 +48,28 @@ function watch(globs, opts, tasks) {
         throw err;
       });
 
+  var log = function watchLogger(triggerCount) {
+    // Don't report change for initial event
+    if (!ignoreInitial && !--triggerCount) return;
+
+    process.stdout.write([
+      '',
+      '==================================================',
+      ' WATCH TRIGGERED BY FILE CHANGE #' + triggerCount,
+      ' On: ' + prettyTime(),
+      '==================================================\n',
+    ].join('\n'));
+
+    function prettyTime() {
+      var now = new Date();
+      return now.toLocaleDateString() + " at " + now.toLocaleTimeString();
+    }
+  }
+
+  if (opts.log !== undefined && !opts.log) {
+    log = function noopLog(triggerCount) {}
+  }
+
   var close = watcher.close.bind(watcher);
   watcher.close = function() {
     if (timeoutId !== null) clearTimeout(timeoutId);
@@ -60,7 +80,8 @@ function watch(globs, opts, tasks) {
   var timeoutId = null; // If non-null, event capture window is open
 
   if (!ignoreInitial) {
-    handleEvent('change', 'madeupFilePath'); // synthetic event to kick off the first task run
+    // synthetic event to kick off the first task run
+    timeoutId = setTimeout(invokeCallback, delay);
   }
 
   return watcher;

tools/build/watch.spec.js

@@ -27,7 +27,7 @@ describe('watch()', function() {
 
   it('should fire callback once for events which occur within `delay` window', function() {
     var cb = jasmine.createSpy('callback');
-    watcher = watch('./$$fake_path/**/*', { delay: 10 }, cb);
+    watcher = watch('./$$fake_path/**/*', { delay: 10, log: false }, cb);
 
     watcher._emit('add', './$$fake_path/test.txt');
     timeout.flush(9);
@@ -61,7 +61,7 @@ describe('watch()', function() {
       expect(timeout.pending).toBe(1);
     }
 
-    var watcher = watch('./$$fake_path/**/*', { delay: 10 }, cb);
+    var watcher = watch('./$$fake_path/**/*', { delay: 10, log: false }, cb);
 
     watcher._emit('change', './$$fake_path/test1.txt');
     expect(timeout.pending).toBe(1);
@@ -81,7 +81,7 @@ describe('watch()', function() {
       done();
     }
 
-    var watcher = watch('./$$fake_path/**/*', { delay: 10 }, cb);
+    var watcher = watch('./$$fake_path/**/*', { delay: 10, log: false }, cb);
 
     watcher._emit('change', './$$fake_path/test1.txt');
     timeout.flush();
@@ -96,7 +96,7 @@ describe('watch()', function() {
 
   it('should cancel pending callback if FSWatcher is closed', function() {
     var cb = jasmine.createSpy('callback');
-    var watcher = watch('./$$fake_path/**/*', { delay: 10 }, cb);
+    var watcher = watch('./$$fake_path/**/*', { delay: 10, log: false }, cb);
 
     watcher._emit('change', './$$fake_path/test1.txt');
     expect(timeout.pending).toBe(1);
@@ -119,7 +119,7 @@ describe('watch()', function() {
       expect(timeout.pending).toBe(0);
     }
 
-    var watcher = watch('./$$fake_path/**/*', { delay: 10 }, cb);
+    var watcher = watch('./$$fake_path/**/*', { delay: 10, log: false }, cb);
     watcher._emit('change', './$$fake_path/test1.txt');
 
     timeout.flush(10);