From be92367a8fe3ebe30e355b978b7ecc7359476bac Mon Sep 17 00:00:00 2001
From: Chris Howey <chris@howey.me>
Date: Tue, 25 Sep 2012 19:57:52 -0500
Subject: [PATCH] BSD - fix to not longer get duplicate CREATE events

needed to add DELETE watch for directories that are created in
watched directory

Also added a test for this behaviour
---
 fsnotify_bsd.go  | 20 +++++++++++++++++---
 fsnotify_test.go | 37 ++++++++++++++++++++++++++++++++++---
 2 files changed, 51 insertions(+), 6 deletions(-)

diff --git a/fsnotify_bsd.go b/fsnotify_bsd.go
index 5ddf578..015648b 100644
--- a/fsnotify_bsd.go
+++ b/fsnotify_bsd.go
@@ -42,6 +42,7 @@ type Watcher struct {
 	fsnFlags      map[string]uint32   // Map of watched files to flags used for filter
 	paths         map[int]string      // Map of watched paths (key: watch descriptor)
 	finfo         map[int]os.FileInfo // Map of file information (isDir, isReg; key: watch descriptor)
+	fileExists    map[string]bool     // Keep track of if we know this file exists (to stop duplicate create events)
 	Error         chan error          // Errors are sent on this channel
 	internalEvent chan *FileEvent     // Events are queued on this channel
 	Event         chan *FileEvent     // Events are returned on this channel
@@ -62,6 +63,7 @@ func NewWatcher() (*Watcher, error) {
 		fsnFlags:      make(map[string]uint32),
 		paths:         make(map[int]string),
 		finfo:         make(map[int]os.FileInfo),
+		fileExists:    make(map[string]bool),
 		internalEvent: make(chan *FileEvent),
 		Event:         make(chan *FileEvent),
 		Error:         make(chan error),
@@ -249,6 +251,10 @@ func (w *Watcher) readEvents() {
 
 			if fileEvent.IsRename() {
 				w.removeWatch(fileEvent.Name)
+				delete(w.fileExists, fileEvent.Name)
+			}
+			if fileEvent.IsDelete() {
+				delete(w.fileExists, fileEvent.Name)
 			}
 		}
 	}
@@ -263,15 +269,22 @@ func (w *Watcher) watchDirectoryFiles(dirPath string) error {
 
 	// Search for new files
 	for _, fileInfo := range files {
+		filePath := filepath.Join(dirPath, fileInfo.Name())
 		if fileInfo.IsDir() == false {
-			filePath := filepath.Join(dirPath, fileInfo.Name())
 			// Watch file to mimic linux fsnotify
 			e := w.addWatch(filePath, NOTE_DELETE|NOTE_WRITE|NOTE_RENAME)
 			w.fsnFlags[filePath] = FSN_ALL
 			if e != nil {
 				return e
 			}
+		} else {
+			// Linux gives deletes if not explicitly watching
+			e := w.addWatch(filePath, NOTE_DELETE)
+			if e != nil {
+				return e
+			}
 		}
+		w.fileExists[filePath] = true
 	}
 
 	return nil
@@ -291,8 +304,8 @@ func (w *Watcher) sendDirectoryChangeEvents(dirPath string) {
 	// Search for new files
 	for _, fileInfo := range files {
 		filePath := filepath.Join(dirPath, fileInfo.Name())
-		_, watchFound := w.watches[filePath]
-		if watchFound == false {
+		_, doesExist := w.fileExists[filePath]
+		if doesExist == false {
 			w.fsnFlags[filePath] = FSN_ALL
 			// Send create event
 			fileEvent := new(FileEvent)
@@ -300,6 +313,7 @@ func (w *Watcher) sendDirectoryChangeEvents(dirPath string) {
 			fileEvent.create = true
 			w.internalEvent <- fileEvent
 		}
+		w.fileExists[filePath] = true
 	}
 	w.watchDirectoryFiles(dirPath)
 }
diff --git a/fsnotify_test.go b/fsnotify_test.go
index f586165..1df2fdb 100644
--- a/fsnotify_test.go
+++ b/fsnotify_test.go
@@ -265,7 +265,9 @@ func TestFsnotifySubDir(t *testing.T) {
 	}
 
 	const testDir string = "_test"
+	const testFile1 string = "_test/TestFsnotifyFile1.testfile"
 	const testSubDir string = "_test/sub"
+	const testSubDirFile string = "_test/sub/TestFsnotifyFile1.testfile"
 
 	// Create directory to watch
 	if os.Mkdir(testDir, 0777) != nil {
@@ -283,15 +285,19 @@ func TestFsnotifySubDir(t *testing.T) {
 	// Receive events on the event channel on a separate goroutine
 	eventstream := watcher.Event
 	var createReceived = 0
+	var deleteReceived = 0
 	done := make(chan bool)
 	go func() {
 		for event := range eventstream {
 			// Only count relevant events
-			if event.Name == testDir || event.Name == testSubDir {
+			if event.Name == testDir || event.Name == testSubDir || event.Name == testFile1 {
 				t.Logf("event received: %s", event)
 				if event.IsCreate() {
 					createReceived++
 				}
+				if event.IsDelete() {
+					deleteReceived++
+				}
 			} else {
 				t.Logf("unexpected event received: %s", event)
 			}
@@ -310,10 +316,35 @@ func TestFsnotifySubDir(t *testing.T) {
 		t.Fatalf("Failed to create test sub-directory: %s", err)
 	}
 
+	// Create a file
+	var f *os.File
+	f, err = os.OpenFile(testFile1, os.O_WRONLY|os.O_CREATE, 0666)
+	if err != nil {
+		t.Fatalf("creating test file failed: %s", err)
+	}
+	f.Sync()
+	f.Close()
+
+	// Create a file (Should not see this! we are not watching subdir)
+	var fs *os.File
+	fs, err = os.OpenFile(testSubDirFile, os.O_WRONLY|os.O_CREATE, 0666)
+	if err != nil {
+		t.Fatalf("creating test file failed: %s", err)
+	}
+	fs.Sync()
+	fs.Close()
+
+	// Make sure receive deletes for both file and sub-directory
+	os.RemoveAll(testSubDir)
+	os.Remove(testFile1)
+
 	// We expect this event to be received almost immediately, but let's wait 500 ms to be sure
 	time.Sleep(500 * time.Millisecond)
-	if createReceived != 1 {
-		t.Fatalf("incorrect number of create events received after 500 ms (%d vs %d)", createReceived, 1)
+	if createReceived != 2 {
+		t.Fatalf("incorrect number of create events received after 500 ms (%d vs %d)", createReceived, 2)
+	}
+	if deleteReceived != 2 {
+		t.Fatalf("incorrect number of delete events received after 500 ms (%d vs %d)", deleteReceived, 2)
 	}
 
 	// Try closing the fsnotify instance
-- 
2.50.1