From 6f48be8da333ecec65e1535dbe59650b527df2db Mon Sep 17 00:00:00 2001
From: Marcel Wiederer <14212817+m-rcl@users.noreply.github.com>
Date: Thu, 8 Sep 2022 16:40:19 +0200
Subject: [PATCH] feat: customizable directory refresher (#45)

This PR is intended to allow users to define the filesystem operations they want to be notified about (for example deletion).
---
 loader/directory_refresher.go | 24 +++++++++++++++-----
 loader/loader_test.go         | 41 +++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/loader/directory_refresher.go b/loader/directory_refresher.go
index 7e17935..d5c45d5 100644
--- a/loader/directory_refresher.go
+++ b/loader/directory_refresher.go
@@ -3,7 +3,14 @@ package loader
 import "path/filepath"
 
 type DirectoryRefresher struct {
-	currDir string
+	currDir  string
+	watchOps map[FileSystemOp]bool
+}
+
+var defaultFileSystemOps = map[FileSystemOp]bool{
+	Write:  true,
+	Create: true,
+	Chmod:  true,
 }
 
 func (d *DirectoryRefresher) WatchDirectory(runtimePath string, appDirPath string) string {
@@ -11,10 +18,17 @@ func (d *DirectoryRefresher) WatchDirectory(runtimePath string, appDirPath strin
 	return d.currDir
 }
 
+func (d *DirectoryRefresher) WatchFileSystemOps(fsops ...FileSystemOp) {
+	d.watchOps = map[FileSystemOp]bool{}
+	for _, op := range fsops {
+		d.watchOps[op] = true
+	}
+}
+
 func (d *DirectoryRefresher) ShouldRefresh(path string, op FileSystemOp) bool {
-	if filepath.Dir(path) == d.currDir &&
-		(op == Write || op == Create || op == Chmod) {
-		return true
+	watchOps := d.watchOps
+	if watchOps == nil {
+		watchOps = defaultFileSystemOps
 	}
-	return false
+	return filepath.Dir(path) == d.currDir && watchOps[op]
 }
diff --git a/loader/loader_test.go b/loader/loader_test.go
index afd365b..dab7460 100644
--- a/loader/loader_test.go
+++ b/loader/loader_test.go
@@ -334,6 +334,47 @@ func TestOnRuntimeChanged(t *testing.T) {
 	})
 }
 
+func TestShouldRefreshDefault(t *testing.T) {
+	assert := require.New(t)
+
+	refresher := DirectoryRefresher{currDir: "/tmp"}
+
+	assert.True(refresher.ShouldRefresh("/tmp/foo", Write))
+
+	assert.False(refresher.ShouldRefresh("/tmp/foo", Remove))
+	assert.False(refresher.ShouldRefresh("/bar/foo", Write))
+	assert.False(refresher.ShouldRefresh("/bar/foo", Remove))
+}
+
+func TestShouldRefreshRemove(t *testing.T) {
+	assert := require.New(t)
+
+	refresher := DirectoryRefresher{currDir: "/tmp", watchOps: map[FileSystemOp]bool{
+		Remove: true,
+		Chmod:  true,
+	}}
+
+	assert.True(refresher.ShouldRefresh("/tmp/foo", Remove))
+	assert.True(refresher.ShouldRefresh("/tmp/foo", Chmod))
+
+	assert.False(refresher.ShouldRefresh("/bar/foo", Write))
+}
+
+func TestWatchFileSystemOps(t *testing.T) {
+	assert := require.New(t)
+
+	refresher := DirectoryRefresher{currDir: "/tmp"}
+
+	refresher.WatchFileSystemOps()
+	assert.False(refresher.ShouldRefresh("/tmp/foo", Write))
+
+	refresher.WatchFileSystemOps(Remove)
+	assert.True(refresher.ShouldRefresh("/tmp/foo", Remove))
+
+	refresher.WatchFileSystemOps(Chmod, Write)
+	assert.True(refresher.ShouldRefresh("/tmp/foo", Write))
+}
+
 func BenchmarkSnapshot(b *testing.B) {
 	var ll Loader
 	for i := 0; i < b.N; i++ {