cli/command/image/build: use t.Chdir() in tests

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

.golangci.yml

@@ -158,11 +158,6 @@ linters:
         - name: use-any           # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md#use-any
         - name: use-errors-new    # https://github.com/mgechev/revive/blob/HEAD/RULES_DESCRIPTIONS.md#use-errors-new
 
-    usetesting:
-      os-chdir: false           # FIXME(thaJeztah): Disable `os.Chdir()` detections; should be automatically disabled on Go < 1.24; see https://github.com/docker/cli/pull/5835#issuecomment-2665302478
-      context-background: false # FIXME(thaJeztah): Disable `context.Background()` detections; should be automatically disabled on Go < 1.24; see https://github.com/docker/cli/pull/5835#issuecomment-2665302478
-      context-todo: false       # FIXME(thaJeztah): Disable `context.TODO()` detections; should be automatically disabled on Go < 1.24; see https://github.com/docker/cli/pull/5835#issuecomment-2665302478
-
   exclusions:
     # We prefer to use an "linters.exclusions.rules" so that new "default" exclusions are not
     # automatically inherited. We can decide whether or not to follow upstream

cli/command/image/build/context_test.go

@@ -68,7 +68,7 @@ func TestGetContextFromLocalDirWithNoDirectory(t *testing.T) {
 	contextDir := createTestTempDir(t)
 	createTestTempFile(t, contextDir, defaultDockerfileName, dockerfileContents)
 
-	chdir(t, contextDir)
+	t.Chdir(contextDir)
 
 	absContextDir, relDockerfile, err := GetContextFromLocalDir(contextDir, "")
 	assert.NilError(t, err)
@@ -110,7 +110,7 @@ func TestGetContextFromLocalDirLocalFile(t *testing.T) {
 
 func TestGetContextFromLocalDirWithCustomDockerfile(t *testing.T) {
 	contextDir := createTestTempDir(t)
-	chdir(t, contextDir)
+	t.Chdir(contextDir)
 
 	createTestTempFile(t, contextDir, defaultDockerfileName, dockerfileContents)
 
@@ -248,20 +248,6 @@ func createTestTempFile(t *testing.T, dir, filename, contents string) string {
 	return filePath
 }
 
-// chdir changes current working directory to dir.
-// It returns a function which changes working directory back to the previous one.
-// This function is meant to be executed as a deferred call.
-// When an error occurs, it terminates the test.
-func chdir(t *testing.T, dir string) {
-	t.Helper()
-	workingDirectory, err := os.Getwd()
-	assert.NilError(t, err)
-	assert.NilError(t, os.Chdir(dir))
-	t.Cleanup(func() {
-		assert.NilError(t, os.Chdir(workingDirectory))
-	})
-}
-
 func TestIsArchive(t *testing.T) {
 	tests := []struct {
 		doc      string