lib/memfs: move the test for NewWatcher and DirWatcher as example

With this we do one thing (write testing) and output two things (testing
the code and give an example for code).

4 files changed, 253 insertions, 287 deletions

diff --git a/lib/memfs/dirwatcher_example_test.go b/lib/memfs/dirwatcher_example_test.go
new file mode 100644
index 00000000..a8468d80
--- /dev/null
+++ b/lib/memfs/dirwatcher_example_test.go
@@ -0,0 +1,168 @@
+// Copyright 2022, Shulhan <ms@kilabit.info>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package memfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+func ExampleDirWatcher() {
+	var (
+		ns      NodeState
+		rootDir string
+		err     error
+	)
+
+	rootDir, err = ioutil.TempDir("", "libmemfs")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// In this example, we watch sub directory "assets" and its contents,
+	// include only file with .adoc extension and ignoring files with
+	// .html extension.
+	dw := &DirWatcher{
+		Options: Options{
+			Root: rootDir,
+			Includes: []string{
+				`assets/.*`,
+				`.*\.adoc$`,
+			},
+			Excludes: []string{
+				`.*\.html$`,
+			},
+		},
+		Delay: 150 * time.Millisecond,
+	}
+
+	err = dw.Start()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Printf("Deleting the root directory:\n")
+	err = os.Remove(rootDir)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s\n", ns.State, ns.Node.Path)
+
+	// Create the root directory back with sub directory
+	// This will trigger two FileStateCreated events, one for "/" and one
+	// for "/assets".
+	dirAssets := filepath.Join(rootDir, "assets")
+	fmt.Printf("Re-create root directory with sub-directory:\n")
+	err = os.MkdirAll(dirAssets, 0770)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s\n", ns.State, ns.Node.Path)
+	ns = <-dw.C
+	fmt.Printf("-- %s %s\n", ns.State, ns.Node.Path)
+
+	// Modify the permission on root directory
+	fmt.Printf("Chmod on root directory:\n")
+	err = os.Chmod(rootDir, 0700)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	newFile := filepath.Join(rootDir, "new.adoc")
+	fmt.Println("Create new file on root directory: /new.adoc")
+	err = ioutil.WriteFile(newFile, nil, 0600)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	fmt.Println("Remove file on root directory: /new.adoc")
+	err = os.Remove(newFile)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	// Create sub-directory.
+	subDir := filepath.Join(rootDir, "subdir")
+	fmt.Println("Create new sub-directory: /subdir")
+	err = os.Mkdir(subDir, 0770)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	// Add new file in sub directory.
+	newFile = filepath.Join(subDir, "new.adoc")
+	fmt.Println("Create new file in sub directory: /subdir/new.adoc")
+	err = ioutil.WriteFile(newFile, nil, 0600)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	fmt.Println("Remove file in sub directory: /subdir/new.adoc")
+	err = os.Remove(newFile)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	// Creating file that is excluded should not trigger event.
+	newFile = filepath.Join(subDir, "new.html")
+	fmt.Println("Create excluded file in sub directory: /subdir/new.html")
+	err = ioutil.WriteFile(newFile, nil, 0600)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Create file without extension in directory "assets" should trigger
+	// event.
+	newFile = filepath.Join(dirAssets, "new")
+	fmt.Println("Create new file under assets: /assets/new")
+	err = ioutil.WriteFile(newFile, nil, 0600)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-dw.C
+	fmt.Printf("-- %s %s %s\n", ns.State, ns.Node.Path, ns.Node.Mode())
+
+	dw.Stop()
+
+	//Output:
+	//Deleting the root directory:
+	//-- FileStateDeleted /
+	//Re-create root directory with sub-directory:
+	//-- FileStateCreated /
+	//-- FileStateCreated /assets
+	//Chmod on root directory:
+	//-- FileStateUpdateMode / drwx------
+	//Create new file on root directory: /new.adoc
+	//-- FileStateCreated /new.adoc -rw-------
+	//Remove file on root directory: /new.adoc
+	//-- FileStateDeleted /new.adoc -rw-------
+	//Create new sub-directory: /subdir
+	//-- FileStateCreated /subdir drwxr-x---
+	//Create new file in sub directory: /subdir/new.adoc
+	//-- FileStateCreated /subdir/new.adoc -rw-------
+	//Remove file in sub directory: /subdir/new.adoc
+	//-- FileStateDeleted /subdir/new.adoc -rw-------
+	//Create excluded file in sub directory: /subdir/new.html
+	//Create new file under assets: /assets/new
+	//-- FileStateCreated /assets/new -rw-------
+}
diff --git a/lib/memfs/dirwatcher_test.go b/lib/memfs/dirwatcher_test.go
index 4bf1cd48..a62f6001 100644
--- a/lib/memfs/dirwatcher_test.go
+++ b/lib/memfs/dirwatcher_test.go
@@ -5,8 +5,6 @@
 package memfs
 
 import (
-	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"testing"
@@ -15,200 +13,6 @@ import (
 	"github.com/shuLhan/share/lib/test"
 )
 
-func TestDirWatcher(t *testing.T) {
-	var (
-		err   error
-		gotNS NodeState
-		dir   string
-		x     int
-	)
-
-	dir = t.TempDir()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	fmt.Printf(">>> Watching directory %q for changes ...\n", dir)
-
-	exps := []struct {
-		path  string
-		state FileState
-	}{{
-		state: FileStateDeleted,
-		path:  "/",
-	}, {
-		state: FileStateCreated,
-		path:  "/",
-	}, {
-		state: FileStateCreated,
-		path:  "/assets",
-	}, {
-		state: FileStateUpdateMode,
-		path:  "/",
-	}, {
-		state: FileStateCreated,
-		path:  "/new.adoc",
-	}, {
-		state: FileStateDeleted,
-		path:  "/new.adoc",
-	}, {
-		state: FileStateCreated,
-		path:  "/sub",
-	}, {
-		state: FileStateCreated,
-		path:  "/sub/new.adoc",
-	}, {
-		state: FileStateDeleted,
-		path:  "/sub/new.adoc",
-	}, {
-		state: FileStateCreated,
-		path:  "/assets/new",
-	}, {
-		state: FileStateDeleted,
-		path:  "/assets/new",
-	}}
-
-	dw := &DirWatcher{
-		Options: Options{
-			Root: dir,
-			Includes: []string{
-				`assets/.*`,
-				`.*\.adoc$`,
-			},
-			Excludes: []string{
-				`.*\.html$`,
-			},
-		},
-		Delay: 150 * time.Millisecond,
-	}
-
-	err = dw.Start()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Delete the directory being watched.
-	t.Logf("Deleting root directory %q ...\n", dir)
-	err = os.Remove(dir)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Create the watched directory back with sub directory
-	// This will trigger two FileStateCreated events, one for "/" and one
-	// for "/assets".
-	dirAssets := filepath.Join(dir, "assets")
-	t.Logf("Re-create root directory %q ...\n", dirAssets)
-	err = os.MkdirAll(dirAssets, 0770)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Modify the permission on root directory
-	t.Logf("Modify root directory %q ...\n", dir)
-	err = os.Chmod(dir, 0700)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Add new file to watched directory.
-	newFile := filepath.Join(dir, "new.adoc")
-	t.Logf("Create new file on root directory: %q ...\n", newFile)
-	err = ioutil.WriteFile(newFile, nil, 0600)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Remove file.
-	t.Logf("Remove file on root directory: %q ...\n", newFile)
-	err = os.Remove(newFile)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Create sub-directory.
-	subDir := filepath.Join(dir, "sub")
-	t.Logf("Create new sub-directory: %q ...\n", subDir)
-	err = os.Mkdir(subDir, 0770)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Add new file in sub directory.
-	newFile = filepath.Join(subDir, "new.adoc")
-	t.Logf("Create new file in sub directory: %q ...\n", newFile)
-	err = ioutil.WriteFile(newFile, nil, 0600)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Remove file in sub directory.
-	t.Logf("Remove file in sub directory: %q ...\n", newFile)
-	err = os.Remove(newFile)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	// Create exclude file, should not trigger event.
-	newFile = filepath.Join(subDir, "new.html")
-	t.Logf("Create excluded file in sub directory: %q ...\n", newFile)
-	err = ioutil.WriteFile(newFile, nil, 0600)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Create file without extension in white list directory "assets",
-	// should trigger event.
-	newFile = filepath.Join(dirAssets, "new")
-	t.Logf("Create new file on assets: %q ...\n", newFile)
-	err = ioutil.WriteFile(newFile, nil, 0600)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-dw.C
-	test.Assert(t, "path", exps[x].path, gotNS.Node.Path)
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	x++
-
-	dw.Stop()
-}
-
 //
 // Test renaming sub-directory being watched.
 //
@@ -270,6 +74,9 @@ func TestDirWatcher_renameDirectory(t *testing.T) {
 	<-dw.C
 	<-dw.C
 
+	// Wait for all watcher finished.
+	time.Sleep(400 * time.Millisecond)
+
 	var expDirs = []string{
 		"/newsubdir",
 	}
diff --git a/lib/memfs/watcher_example_test.go b/lib/memfs/watcher_example_test.go
new file mode 100644
index 00000000..9ef7d8e2
--- /dev/null
+++ b/lib/memfs/watcher_example_test.go
@@ -0,0 +1,82 @@
+// Copyright 2022, Shulhan <ms@kilabit.info>. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package memfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"time"
+)
+
+func ExampleNewWatcher() {
+	var (
+		content = "Content of file"
+
+		f       *os.File
+		watcher *Watcher
+		ns      NodeState
+		err     error
+	)
+
+	// Create a file to be watched.
+	f, err = ioutil.TempFile("", "watcher")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	watcher, err = NewWatcher(f.Name(), 150*time.Millisecond)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Update file mode.
+	err = f.Chmod(0700)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	ns = <-watcher.C
+	fmt.Printf("State: %s\n", ns.State)
+	fmt.Printf("File mode: %s\n", ns.Node.Mode())
+	fmt.Printf("File size: %d\n", ns.Node.Size())
+
+	// Update content of file.
+	_, err = f.WriteString(content)
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-watcher.C
+	fmt.Printf("State: %s\n", ns.State)
+	fmt.Printf("File mode: %s\n", ns.Node.Mode())
+	fmt.Printf("File size: %d\n", ns.Node.Size())
+
+	err = f.Close()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Remove the file.
+	err = os.Remove(f.Name())
+	if err != nil {
+		log.Fatal(err)
+	}
+	ns = <-watcher.C
+	fmt.Printf("State: %s\n", ns.State)
+	fmt.Printf("File mode: %s\n", ns.Node.Mode())
+	fmt.Printf("File size: %d\n", ns.Node.Size())
+
+	//Output:
+	//State: FileStateUpdateMode
+	//File mode: -rwx------
+	//File size: 0
+	//State: FileStateUpdateContent
+	//File mode: -rwx------
+	//File size: 15
+	//State: FileStateDeleted
+	//File mode: -rwx------
+	//File size: 15
+}
diff --git a/lib/memfs/watcher_test.go b/lib/memfs/watcher_test.go
deleted file mode 100644
index 30693b7f..00000000
--- a/lib/memfs/watcher_test.go
+++ /dev/null
@@ -1,91 +0,0 @@
-// Copyright 2018, Shulhan <ms@kilabit.info>. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package memfs
-
-import (
-	"io/ioutil"
-	"os"
-	"testing"
-	"time"
-
-	"github.com/shuLhan/share/lib/test"
-)
-
-type caseWatcher struct {
-	state FileState
-	mode  os.FileMode
-	size  int64
-}
-
-func TestWatcher(t *testing.T) {
-	var (
-		content = "Write changes"
-
-		f       *os.File
-		watcher *Watcher
-		gotNS   NodeState
-		err     error
-		x       int
-	)
-
-	f, err = ioutil.TempFile("", "watcher")
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	exps := []caseWatcher{{
-		state: FileStateUpdateMode,
-		mode:  0700,
-	}, {
-		state: FileStateUpdateContent,
-		mode:  0700,
-		size:  int64(len(content)),
-	}, {
-		state: FileStateDeleted,
-		mode:  0700,
-		size:  int64(len(content)),
-	}}
-
-	watcher, err = NewWatcher(f.Name(), 150*time.Millisecond)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	// Update file mode
-	err = f.Chmod(0700)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-watcher.C
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	test.Assert(t, "file mode", exps[x].mode, gotNS.Node.Mode())
-	test.Assert(t, "file size", exps[x].size, gotNS.Node.Size())
-	x++
-
-	_, err = f.WriteString(content)
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-watcher.C
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	test.Assert(t, "file mode", exps[x].mode, gotNS.Node.Mode())
-	test.Assert(t, "file size", exps[x].size, gotNS.Node.Size())
-	x++
-
-	err = f.Close()
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	err = os.Remove(f.Name())
-	if err != nil {
-		t.Fatal(err)
-	}
-	gotNS = <-watcher.C
-	test.Assert(t, "state", exps[x].state, gotNS.State)
-	test.Assert(t, "file mode", exps[x].mode, gotNS.Node.Mode())
-	test.Assert(t, "file size", exps[x].size, gotNS.Node.Size())
-	x++
-}