use afero filesystem for createAppFromSubdir instead of os calls

Author: srtaalej

internal/pkg/create/create.go

@@ -380,19 +380,20 @@ func normalizeSubdir(subdir string) (string, error) {
 // createAppFromSubdir clones the full template into a temp directory, then copies
 // only the specified subdirectory to the final project path.
 func createAppFromSubdir(ctx context.Context, dirPath string, template Template, gitBranch string, subdir string, log *logger.Logger, fs afero.Fs) error {
-	tmpDir, err := os.MkdirTemp("", "slack-create-*")
+	tmpDirRoot := afero.GetTempDir(fs, "")
+	tmpDir, err := afero.TempDir(fs, tmpDirRoot, "slack-create-")
 	if err != nil {
 		return slackerror.Wrap(err, "failed to create temporary directory")
 	}
-	defer os.RemoveAll(tmpDir)
+	defer func() { _ = fs.RemoveAll(tmpDir) }()
 
 	cloneDir := filepath.Join(tmpDir, "repo")
 	if err := createApp(ctx, cloneDir, template, gitBranch, log, fs); err != nil {
 		return err
 	}
 
 	subdirPath := filepath.Join(cloneDir, subdir)
-	info, err := os.Stat(subdirPath)
+	info, err := fs.Stat(subdirPath)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return slackerror.New(slackerror.ErrSubdirNotFound).

internal/pkg/create/create_test.go

@@ -17,7 +17,6 @@ package create
 import (
 	"fmt"
 	"net/http"
-	"os"
 	"path/filepath"
 	"testing"
 
@@ -239,38 +238,38 @@ func TestNormalizeSubdir(t *testing.T) {
 
 func TestCreateAppFromSubdir(t *testing.T) {
 	tests := map[string]struct {
-		setupTemplate func(t *testing.T) string
+		setupTemplate func(t *testing.T, fs afero.Fs) string
 		subdir        string
 		expectError   bool
 		errorContains string
 		expectFiles   []string
 	}{
 		"extracts subdirectory from local template": {
-			setupTemplate: func(t *testing.T) string {
+			setupTemplate: func(t *testing.T, fs afero.Fs) string {
 				tmpDir := t.TempDir()
 				// Create a subdirectory with a file
 				subdir := filepath.Join(tmpDir, "apps", "my-app")
-				require.NoError(t, os.MkdirAll(subdir, 0755))
-				require.NoError(t, os.WriteFile(filepath.Join(subdir, "manifest.json"), []byte(`{}`), 0644))
+				require.NoError(t, fs.MkdirAll(subdir, 0755))
+				require.NoError(t, afero.WriteFile(fs, filepath.Join(subdir, "manifest.json"), []byte(`{}`), 0644))
 				// Create a file at root that should NOT be copied
-				require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "README.md"), []byte("root readme"), 0644))
+				require.NoError(t, afero.WriteFile(fs, filepath.Join(tmpDir, "README.md"), []byte("root readme"), 0644))
 				return tmpDir
 			},
 			subdir:      "apps/my-app",
 			expectFiles: []string{"manifest.json"},
 		},
 		"returns error for nonexistent subdirectory": {
-			setupTemplate: func(t *testing.T) string {
+			setupTemplate: func(t *testing.T, fs afero.Fs) string {
 				return t.TempDir()
 			},
 			subdir:        "nonexistent",
 			expectError:   true,
 			errorContains: "was not found in the template",
 		},
 		"returns error when subdir path is a file": {
-			setupTemplate: func(t *testing.T) string {
+			setupTemplate: func(t *testing.T, fs afero.Fs) string {
 				tmpDir := t.TempDir()
-				require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "not-a-dir"), []byte("file"), 0644))
+				require.NoError(t, afero.WriteFile(fs, filepath.Join(tmpDir, "not-a-dir"), []byte("file"), 0644))
 				return tmpDir
 			},
 			subdir:        "not-a-dir",
@@ -280,14 +279,14 @@ func TestCreateAppFromSubdir(t *testing.T) {
 	}
 	for name, tc := range tests {
 		t.Run(name, func(t *testing.T) {
-			templateDir := tc.setupTemplate(t)
+			fs := afero.NewOsFs()
+			templateDir := tc.setupTemplate(t, fs)
 			outputDir := t.TempDir()
 			// Remove output dir so CopyDirectory can create it
-			require.NoError(t, os.Remove(outputDir))
+			require.NoError(t, fs.Remove(outputDir))
 
 			template := Template{path: templateDir, isLocal: true}
 			log := logger.New(func(event *logger.LogEvent) {})
-			fs := afero.NewOsFs()
 
 			err := createAppFromSubdir(t.Context(), outputDir, template, "", tc.subdir, log, fs)
 
@@ -299,7 +298,7 @@ func TestCreateAppFromSubdir(t *testing.T) {
 			} else {
 				assert.NoError(t, err)
 				for _, f := range tc.expectFiles {
-					_, statErr := os.Stat(filepath.Join(outputDir, f))
+					_, statErr := fs.Stat(filepath.Join(outputDir, f))
 					assert.NoError(t, statErr, "expected file %s to exist", f)
 				}
 			}