hg: refactor for later evolutions

pkg/vendir/fetch/hg/hg.go

@@ -21,12 +21,19 @@ type Hg struct {
 	opts       ctlconf.DirectoryContentsHg
 	infoLog    io.Writer
 	refFetcher ctlfetch.RefFetcher
+	authDir    string
+	env        []string
 }
 
 func NewHg(opts ctlconf.DirectoryContentsHg,
-	infoLog io.Writer, refFetcher ctlfetch.RefFetcher) *Hg {
-
-	return &Hg{opts, infoLog, refFetcher}
+	infoLog io.Writer, refFetcher ctlfetch.RefFetcher,
+	tempArea ctlfetch.TempArea,
+) (*Hg, error) {
+	t := Hg{opts, infoLog, refFetcher, "", nil}
+	if err := t.setup(tempArea); err != nil {
+		return nil, err
+	}
+	return &t, nil
 }
 
 //nolint:revive
@@ -48,14 +55,14 @@ func (t *Hg) Retrieve(dstPath string, tempArea ctlfetch.TempArea) (HgInfo, error
 	info := HgInfo{}
 
 	// use hg log to retrieve full cset sha
-	out, _, err := t.run([]string{"log", "-r", ".", "-T", "{node}"}, nil, dstPath)
+	out, _, err := t.run([]string{"log", "-r", ".", "-T", "{node}"}, dstPath)
 	if err != nil {
 		return HgInfo{}, err
 	}
 
 	info.SHA = strings.TrimSpace(out)
 
-	out, _, err = t.run([]string{"log", "-l", "1", "-T", "{desc|firstline|strip}", "-r", info.SHA}, nil, dstPath)
+	out, _, err = t.run([]string{"log", "-l", "1", "-T", "{desc|firstline|strip}", "-r", info.SHA}, dstPath)
 	if err != nil {
 		return HgInfo{}, err
 	}
@@ -65,7 +72,14 @@ func (t *Hg) Retrieve(dstPath string, tempArea ctlfetch.TempArea) (HgInfo, error
 	return info, nil
 }
 
-func (t *Hg) fetch(dstPath string, tempArea ctlfetch.TempArea) error {
+func (t *Hg) Close() {
+	if t.authDir != "" {
+		os.RemoveAll(t.authDir)
+		t.authDir = ""
+	}
+}
+
+func (t *Hg) setup(tempArea ctlfetch.TempArea) error {
 	authOpts, err := t.getAuthOpts()
 	if err != nil {
 		return err
@@ -76,17 +90,12 @@ func (t *Hg) fetch(dstPath string, tempArea ctlfetch.TempArea) error {
 		return err
 	}
 
-	defer os.RemoveAll(authDir)
+	t.authDir = authDir
 
-	env := os.Environ()
+	t.env = os.Environ()
 
 	hgURL := t.opts.URL
 
-	_, _, err = t.run([]string{"init"}, env, dstPath)
-	if err != nil {
-		return err
-	}
-
 	var hgRc string
 
 	if t.opts.Evolve {
@@ -147,39 +156,56 @@ hgauth.password = %s
 		if err != nil {
 			return fmt.Errorf("Writing %s: %s", hgRcPath, err)
 		}
-		env = append(env, "HGRCPATH="+hgRcPath)
+		t.env = append(t.env, "HGRCPATH="+hgRcPath)
+	}
+
+	return nil
+}
+
+func (t *Hg) initClone(dstPath string) error {
+	hgURL := t.opts.URL
+
+	if _, _, err := t.run([]string{"init"}, dstPath); err != nil {
+		return err
 	}
 
 	repoHgRcPath := filepath.Join(dstPath, ".hg", "hgrc")
 
 	repoHgRc := fmt.Sprintf("[paths]\ndefault = %s\n", hgURL)
 
-	err = os.WriteFile(repoHgRcPath, []byte(repoHgRc), 0600)
-	if err != nil {
+	if err := os.WriteFile(repoHgRcPath, []byte(repoHgRc), 0600); err != nil {
 		return fmt.Errorf("Writing %s: %s", repoHgRcPath, err)
 	}
 
+	return nil
+}
+
+func (t *Hg) fetch(dstPath string, tempArea ctlfetch.TempArea) error {
+	if err := t.initClone(dstPath); err != nil {
+		return err
+	}
+
 	return t.runMultiple([][]string{
 		{"pull"},
 		{"checkout", t.opts.Ref},
-	}, env, dstPath)
+	}, dstPath)
 }
 
-func (t *Hg) runMultiple(argss [][]string, env []string, dstPath string) error {
+func (t *Hg) runMultiple(argss [][]string, dstPath string) error {
 	for _, args := range argss {
-		_, _, err := t.run(args, env, dstPath)
+		_, _, err := t.run(args, dstPath)
 		if err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func (t *Hg) run(args []string, env []string, dstPath string) (string, string, error) {
+func (t *Hg) run(args []string, dstPath string) (string, string, error) {
 	var stdoutBs, stderrBs bytes.Buffer
 
 	cmd := exec.Command("hg", args...)
-	cmd.Env = env
+	cmd.Env = t.env
 	cmd.Dir = dstPath
 	cmd.Stdout = io.MultiWriter(t.infoLog, &stdoutBs)
 	cmd.Stderr = io.MultiWriter(t.infoLog, &stderrBs)

pkg/vendir/fetch/hg/sync.go

@@ -44,7 +44,11 @@ func (d Sync) Sync(dstPath string, tempArea ctlfetch.TempArea) (ctlconf.LockDire
 
 	defer os.RemoveAll(incomingTmpPath)
 
-	hg := NewHg(d.opts, d.log, d.refFetcher)
+	hg, err := NewHg(d.opts, d.log, d.refFetcher, tempArea)
+	if err != nil {
+		return hgLockConf, err
+	}
+	defer hg.Close()
 
 	info, err := hg.Retrieve(incomingTmpPath, tempArea)
 	if err != nil {