From f174f957f0fdd3f31fc784318e30cdd58df878f1 Mon Sep 17 00:00:00 2001
From: Arne Groskurth <arnegroskurth@users.noreply.github.com>
Date: Sun, 31 Jul 2022 21:16:05 +0200
Subject: [PATCH] windows: update watch paths when renaming directories with
 sub-watches (#370)

Fixes #259
Fixes #243

Co-authored-by: Martin Tournoij <martin@arp242.net>
---
 helpers_test.go     |  6 ++++++
 integration_test.go | 30 ++++++++++++++++++++++++++++++
 windows.go          | 13 +++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/helpers_test.go b/helpers_test.go
index cb2f1212..08164fd0 100644
--- a/helpers_test.go
+++ b/helpers_test.go
@@ -411,6 +411,12 @@ func newEvents(t *testing.T, s string) Events {
 	if e, ok := events[runtime.GOOS]; ok {
 		return e
 	}
+	switch runtime.GOOS {
+	case "freebsd", "netbsd", "openbsd", "dragonfly", "darwin":
+		if e, ok := events["kqueue"]; ok {
+			return e
+		}
+	}
 	return events[""]
 }
 
diff --git a/integration_test.go b/integration_test.go
index 6ae1ae07..28b846c6 100644
--- a/integration_test.go
+++ b/integration_test.go
@@ -164,6 +164,36 @@ func TestWatchRename(t *testing.T) {
 			windows:
 				create /renamed
 		`},
+
+		{"rename watched directory", func(t *testing.T, w *Watcher, tmp string) {
+			addWatch(t, w, tmp)
+
+			dir := filepath.Join(tmp, "dir")
+			mkdir(t, dir)
+			addWatch(t, w, dir)
+
+			mv(t, dir, tmp, "dir-renamed")
+			touch(t, tmp, "dir-renamed/file")
+		}, `
+			CREATE   "/dir"           # mkdir
+			RENAME   "/dir"           # mv
+			CREATE   "/dir-renamed"
+			RENAME   "/dir"
+			CREATE   "/dir/file"      # touch
+
+			windows:
+				CREATE       "/dir"                 # mkdir
+				RENAME       "/dir"                 # mv
+				CREATE       "/dir-renamed"
+				CREATE       "/dir-renamed/file"    # touch
+
+			# TODO: no results for the touch; this is probably a bug; windows
+			# was fixed in #370.
+			kqueue:
+				CREATE               "/dir"           # mkdir
+				CREATE               "/dir-renamed"   # mv
+				REMOVE|RENAME        "/dir"
+		`},
 	}
 
 	for _, tt := range tests {
diff --git a/windows.go b/windows.go
index ecae0ce1..c8899048 100644
--- a/windows.go
+++ b/windows.go
@@ -14,6 +14,7 @@ import (
 	"path/filepath"
 	"reflect"
 	"runtime"
+	"strings"
 	"sync"
 	"syscall"
 	"unsafe"
@@ -500,6 +501,18 @@ func (w *Watcher) readEvents() {
 			case syscall.FILE_ACTION_RENAMED_OLD_NAME:
 				watch.rename = name
 			case syscall.FILE_ACTION_RENAMED_NEW_NAME:
+				// Update saved path of all sub-watches.
+				old := filepath.Join(watch.path, watch.rename)
+				w.mu.Lock()
+				for _, watchMap := range w.watches {
+					for _, ww := range watchMap {
+						if strings.HasPrefix(ww.path, old) {
+							ww.path = filepath.Join(fullname, strings.TrimPrefix(ww.path, old))
+						}
+					}
+				}
+				w.mu.Unlock()
+
 				if watch.names[watch.rename] != 0 {
 					watch.names[name] |= watch.names[watch.rename]
 					delete(watch.names, watch.rename)