Use FSEventsWatcher as default on darwin

* eventwatcher_darwin.go
  * NewEventWather returns fsEventWatehr

* eventwatcher_other.go
  * NewEventWather returns fsNotifyWatcher

watcher/batcher.go

@@ -14,7 +14,6 @@
 package watcher
 
 import (
-	"runtime"
 	"time"
 
 	"github.com/fsnotify/fsnotify"
@@ -39,8 +38,6 @@ func New(intervalBatcher, intervalPoll time.Duration, poll bool) (*Batcher, erro
 
 	if poll {
 		watcher = filenotify.NewPollingWatcher(intervalPoll)
-	} else if runtime.GOOS == "darwin" {
-		watcher, err = filenotify.NewFSEventsWatcher()
 	} else {
 		watcher, err = filenotify.New(intervalPoll)
 	}

watcher/filenotify/fsevents_darwin.go → watcher/filenotify/eventwatcher_darwin.go

@@ -308,3 +308,8 @@ func NewFSEventsWatcher() (FileWatcher, error) {
 	}
 	return w, nil
 }
+
+// NewEventWatcher returns an FSEvents based file watcher on darwin
+func NewEventWatcher() (FileWatcher, error) {
+	return NewFSEventsWatcher()
+}

watcher/filenotify/fsevents_others.go → watcher/filenotify/eventwatcher_other.go

@@ -16,6 +16,7 @@
 
 package filenotify
 
-func NewFSEventsWatcher() (FileWatcher, error) {
-	return NewEventWatcher()
+// NewEventWatcher returns an fsnotify based file watcher
+func NewEventWatcher() (FileWatcher, error) {
+	return NewFsNotifyWatcher()
 }

watcher/filenotify/filenotify.go

@@ -38,12 +38,3 @@ func NewPollingWatcher(interval time.Duration) FileWatcher {
 		errors:   make(chan error),
 	}
 }
-
-// NewEventWatcher returns an fs-event based file watcher
-func NewEventWatcher() (FileWatcher, error) {
-	watcher, err := fsnotify.NewWatcher()
-	if err != nil {
-		return nil, err
-	}
-	return &fsNotifyWatcher{watcher}, nil
-}

watcher/filenotify/fsevents_test.go

@@ -85,10 +85,12 @@ func TestFSEventsEvent(t *testing.T) {
 	c.Run(fmt.Sprintf("%s, Add should not trigger event", "fsevents"), func(c *qt.C) {
 		dir, w := prepareFSEventsTest(c, method)
 		subdir := filepath.Join(dir, subdir1)
-		w.Add(subdir)
 
-		// It is rare but this may catch CREATE event of prepareFSEventsTest?
+		// might contain CREATE event derived from preparation, try to remove.
+		drainEvents(c, w)
+		w.Add(subdir)
 		assertEvents(c, w)
+
 		// Create a new sub directory and add it to the watcher.
 		subdir = filepath.Join(dir, subdir1, subdir2)
 		c.Assert(os.Mkdir(subdir, 0777), qt.IsNil)

watcher/filenotify/fsnotify.go

@@ -18,3 +18,11 @@ func (w *fsNotifyWatcher) Events() <-chan fsnotify.Event {
 func (w *fsNotifyWatcher) Errors() <-chan error {
 	return w.Watcher.Errors
 }
+
+func NewFsNotifyWatcher() (FileWatcher, error) {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		return nil, err
+	}
+	return &fsNotifyWatcher{watcher}, nil
+}

watcher/filenotify/poller_test.go

@@ -247,7 +247,7 @@ func preparePollTest(c *qt.C, poll bool) (string, FileWatcher) {
 		w = NewPollingWatcher(watchWaitTime)
 	} else {
 		var err error
-		w, err = NewEventWatcher()
+		w, err = NewFsNotifyWatcher()
 		c.Assert(err, qt.IsNil)
 	}