From 45592a9881899ac6823cf12c681ca29808072614 Mon Sep 17 00:00:00 2001
From: Brian McGee <brian@bmcgee.ie>
Date: Sat, 19 Oct 2024 10:39:21 +0100
Subject: [PATCH] feat: add test helper for changing work directory

Signed-off-by: Brian McGee <brian@bmcgee.ie>
---
 cmd/root_test.go | 22 ++--------------------
 test/test.go     | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/cmd/root_test.go b/cmd/root_test.go
index 8343deec..5dc5abb7 100644
--- a/cmd/root_test.go
+++ b/cmd/root_test.go
@@ -27,18 +27,9 @@ import (
 func TestOnUnmatched(t *testing.T) {
 	as := require.New(t)
 
-	// capture current cwd, so we can replace it after the test is finished
-	cwd, err := os.Getwd()
-	as.NoError(err)
-
-	t.Cleanup(func() {
-		// return to the previous working directory
-		as.NoError(os.Chdir(cwd))
-	})
-
 	tempDir := test.TempExamples(t)
 
-	as.NoError(os.Chdir(tempDir), "failed to change to temp dir")
+	test.ChangeWorkDir(t, tempDir)
 
 	paths := []string{
 		"go/go.mod",
@@ -130,17 +121,8 @@ func TestCpuProfile(t *testing.T) {
 	as := require.New(t)
 	tempDir := test.TempExamples(t)
 
-	// capture current cwd, so we can replace it after the test is finished
-	cwd, err := os.Getwd()
-	as.NoError(err)
-
-	t.Cleanup(func() {
-		// return to the previous working directory
-		as.NoError(os.Chdir(cwd))
-	})
+	test.ChangeWorkDir(t, tempDir)
 
-	// change to temp dir
-	as.NoError(os.Chdir(tempDir), "failed to change to temp dir")
 	// allow missing formatter
 	t.Setenv("TREEFMT_ALLOW_MISSING_FORMATTER", "true")
 
diff --git a/test/test.go b/test/test.go
index 6939474a..909cb3ec 100644
--- a/test/test.go
+++ b/test/test.go
@@ -79,3 +79,27 @@ func Lutimes(t *testing.T, path string, atime time.Time, mtime time.Time) error
 
 	return nil
 }
+
+// ChangeWorkDir changes the current working directory for the duration of the test.
+// The original directory is restored when the test ends.
+func ChangeWorkDir(t *testing.T, dir string) {
+	t.Helper()
+
+	// capture current cwd, so we can replace it after the test is finished
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(fmt.Errorf("failed to get current working directory: %w", err))
+	}
+
+	t.Cleanup(func() {
+		// return to the previous working directory
+		if err := os.Chdir(cwd); err != nil {
+			t.Fatal(fmt.Errorf("failed to return to the previous working directory: %w", err))
+		}
+	})
+
+	// change to the new directory
+	if err := os.Chdir(dir); err != nil {
+		t.Fatal(fmt.Errorf("failed to change working directory to %s: %w", dir, err))
+	}
+}