test: use `T.TempDir` to create temporary test directory

This commit replaces `ioutil.TempDir` with `t.TempDir` in tests. The
directory created by `t.TempDir` is automatically removed when the test
and all its subtests complete.

Prior to this commit, temporary directory created using `ioutil.TempDir`
needs to be removed manually by calling `os.RemoveAll`, which is omitted
in some tests. The error handling boilerplate e.g.
	defer func() {
		if err := os.RemoveAll(dir); err != nil {
			t.Fatal(err)
		}
	}
is also tedious, but `t.TempDir` handles this for us nicely.

Reference: https://pkg.go.dev/testing#T.TempDir
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>

3 files changed, 17 insertions, 59 deletions

diff --git a/pkg/hooks/hooks_test.go b/pkg/hooks/hooks_test.go
index fb3c63250..d5d0c2a32 100644
--- a/pkg/hooks/hooks_test.go
+++ b/pkg/hooks/hooks_test.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io/ioutil"
-	"os"
 	"path/filepath"
 	"runtime"
 	"testing"
@@ -20,11 +19,7 @@ var path string
 func TestGoodNew(t *testing.T) {
 	ctx := context.Background()
 
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	for i, name := range []string{
 		"01-my-hook.json",
@@ -36,7 +31,7 @@ func TestGoodNew(t *testing.T) {
 		if i == 0 {
 			extraStages = ", \"poststart\", \"poststop\""
 		}
-		err = ioutil.WriteFile(jsonPath, []byte(fmt.Sprintf("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"%s\", \"timeout\": %d}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"%s]}", path, i+1, extraStages)), 0644)
+		err := ioutil.WriteFile(jsonPath, []byte(fmt.Sprintf("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"%s\", \"timeout\": %d}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"%s]}", path, i+1, extraStages)), 0644)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -92,14 +87,10 @@ func TestGoodNew(t *testing.T) {
 func TestBadNew(t *testing.T) {
 	ctx := context.Background()
 
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	jsonPath := filepath.Join(dir, "a.json")
-	err = ioutil.WriteFile(jsonPath, []byte("{\"version\": \"-1\"}"), 0644)
+	err := ioutil.WriteFile(jsonPath, []byte("{\"version\": \"-1\"}"), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/pkg/hooks/monitor_test.go b/pkg/hooks/monitor_test.go
index eed02e033..1067d2920 100644
--- a/pkg/hooks/monitor_test.go
+++ b/pkg/hooks/monitor_test.go
@@ -15,11 +15,7 @@ import (
 
 func TestMonitorOneDirGood(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	manager, err := New(ctx, []string{dir}, []string{})
 	if err != nil {
@@ -114,17 +110,8 @@ func TestMonitorOneDirGood(t *testing.T) {
 
 func TestMonitorTwoDirGood(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
-	primaryDir, err := ioutil.TempDir("", "hooks-test-primary-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(primaryDir)
-
-	fallbackDir, err := ioutil.TempDir("", "hooks-test-fallback-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(fallbackDir)
+	primaryDir := t.TempDir()
+	fallbackDir := t.TempDir()
 
 	manager, err := New(ctx, []string{fallbackDir, primaryDir}, []string{})
 	if err != nil {
diff --git a/pkg/hooks/read_test.go b/pkg/hooks/read_test.go
index 6e6c190bb..381d66bbe 100644
--- a/pkg/hooks/read_test.go
+++ b/pkg/hooks/read_test.go
@@ -29,14 +29,10 @@ func TestUnknownPath(t *testing.T) {
 }
 
 func TestGoodFile(t *testing.T) {
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	jsonPath := filepath.Join(dir, "hook.json")
-	err = ioutil.WriteFile(jsonPath, []byte(fmt.Sprintf("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"%s\"}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"]}", path)), 0644)
+	err := ioutil.WriteFile(jsonPath, []byte(fmt.Sprintf("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"%s\"}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"]}", path)), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -59,14 +55,10 @@ func TestGoodFile(t *testing.T) {
 }
 
 func TestBadFile(t *testing.T) {
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	path := filepath.Join(dir, "hook.json")
-	err = ioutil.WriteFile(path, []byte("{\"version\": \"1.0.0\", \"hook\": \"not-a-string\"}"), 0644)
+	err := ioutil.WriteFile(path, []byte("{\"version\": \"1.0.0\", \"hook\": \"not-a-string\"}"), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -121,13 +113,9 @@ func TestInvalidCurrentJSON(t *testing.T) {
 }
 
 func TestGoodDir(t *testing.T) {
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
-	err = ioutil.WriteFile(filepath.Join(dir, "README"), []byte("not a hook"), 0644)
+	err := ioutil.WriteFile(filepath.Join(dir, "README"), []byte("not a hook"), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -172,14 +160,10 @@ func TestUnknownDir(t *testing.T) {
 }
 
 func TestBadDir(t *testing.T) {
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	jsonPath := filepath.Join(dir, "a.json")
-	err = ioutil.WriteFile(jsonPath, []byte("{\"version\": \"-1\"}"), 0644)
+	err := ioutil.WriteFile(jsonPath, []byte("{\"version\": \"-1\"}"), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -193,14 +177,10 @@ func TestBadDir(t *testing.T) {
 }
 
 func TestHookExecutableDoesNotExit(t *testing.T) {
-	dir, err := ioutil.TempDir("", "hooks-test-")
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer os.RemoveAll(dir)
+	dir := t.TempDir()
 
 	jsonPath := filepath.Join(dir, "hook.json")
-	err = ioutil.WriteFile(jsonPath, []byte("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"/does/not/exist\"}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"]}"), 0644)
+	err := ioutil.WriteFile(jsonPath, []byte("{\"version\": \"1.0.0\", \"hook\": {\"path\": \"/does/not/exist\"}, \"when\": {\"always\": true}, \"stages\": [\"prestart\"]}"), 0644)
 	if err != nil {
 		t.Fatal(err)
 	}