try some more tsting

internal/fswatcher/inotify.go

@@ -0,0 +1,58 @@
+package fswatcher
+
+import (
+	"fmt"
+
+	"golang.org/x/sys/unix"
+)
+
+type Inotify struct {
+	fd       int
+	watchers map[int]*watcher
+}
+
+func NewInotify() (*Inotify, error) {
+	fd, errno := unix.InotifyInit1(unix.IN_CLOEXEC)
+	if fd == -1 {
+		return nil, fmt.Errorf("Can't init inotify: %d", errno)
+	}
+
+	i := &Inotify{
+		fd:       fd,
+		watchers: make(map[int]*watcher),
+	}
+
+	return i, nil
+}
+
+func (i *Inotify) Watch(dir string) error {
+	w, err := newWatcher(i.fd, dir)
+	if err != nil {
+		return fmt.Errorf("creating watcher: %v", err)
+	}
+	i.watchers[w.wd] = w
+	return nil
+}
+
+func (i *Inotify) Close() error {
+	if err := unix.Close(i.fd); err != nil {
+		return fmt.Errorf("closing inotify file descriptor: %v", err)
+	}
+	return nil
+}
+
+func (i *Inotify) NumWatchers() int {
+	return len(i.watchers)
+}
+
+func (i *Inotify) String() string {
+	if len(i.watchers) < 20 {
+		dirs := make([]string, 0)
+		for _, w := range i.watchers {
+			dirs = append(dirs, w.dir)
+		}
+		return fmt.Sprintf("Watching: %v", dirs)
+	} else {
+		return fmt.Sprintf("Watching %d directories", len(i.watchers))
+	}
+}