package watcher import ( "bufio" "os" "testing" "time" "github.com/stretchr/testify/assert" ) type mockNotifier struct { eventPath string } func (n *mockNotifier) WatcherItemDidChange(path string) { n.eventPath = path } func (n *mockNotifier) WatcherDidError(err error) { } func TestFileChanged(t *testing.T) { filePath := "test_file" f, err := os.Create(filePath) assert.NoError(t, err) defer func() { f.Close() os.Remove(filePath) }() service, err := NewFile() assert.NoError(t, err) err = service.Add(filePath) assert.NoError(t, err) n := &mockNotifier{} go service.Start(n) f.Sync() w := bufio.NewWriter(f) _, err = w.WriteString("hello Austin, do you like my file watcher?\n") assert.NoError(t, err) err = w.Flush() assert.NoError(t, err) // give it time to trigger time.Sleep(20 * time.Millisecond) service.Shutdown() assert.Equal(t, filePath, n.eventPath, "notifier didn't get an new file write event") }