Remove last git shell-out and fix dropped commit label

internal/cmd/cli/apply.go

@@ -4,9 +4,10 @@ import (
 	"bytes"
 	"fmt"
 	"os"
-	"os/exec"
 	"strings"
 
+	gogit "github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	ctrl "sigs.k8s.io/controller-runtime"
@@ -99,7 +100,7 @@ func (a *Apply) Run(cmd *cobra.Command, args []string) error {
 func (a *Apply) run(cmd *cobra.Command, args []string) error {
 	labels := a.Label
 	if a.Commit == "" {
-		a.Commit = currentCommit()
+		a.Commit = currentCommit(".")
 	}
 	if a.Commit != "" {
 		if labels == nil {
@@ -115,7 +116,7 @@ func (a *Apply) run(cmd *cobra.Command, args []string) error {
 		Output:                       writer.NewDefaultNone(a.Output),
 		Compress:                     a.Compress,
 		ServiceAccount:               a.ServiceAccount,
-		Labels:                       a.Label,
+		Labels:                       labels,
 		TargetsFile:                  a.TargetsFile,
 		TargetNamespace:              a.TargetNamespace,
 		Paused:                       a.Paused,
@@ -243,15 +244,18 @@ func (a *Apply) addAuthToOpts(opts *apply.Options, readFile readFile, helmBasicH
 	return nil
 }
 
-func currentCommit() string {
-	cmd := exec.Command("git", "rev-parse", "HEAD") //nolint:noctx // TODO: refactor to use go-git's ResolveRevision
-	buf := &bytes.Buffer{}
-	cmd.Stdout = buf
-	err := cmd.Run()
-	if err == nil {
-		return strings.TrimSpace(buf.String())
+// currentCommit returns the HEAD commit SHA of the git repository
+// containing dir, or "" if dir is not inside a git repository.
+func currentCommit(dir string) string {
+	repo, err := gogit.PlainOpenWithOptions(dir, &gogit.PlainOpenOptions{DetectDotGit: true})
+	if err != nil {
+		return ""
+	}
+	hash, err := repo.ResolveRevision(plumbing.Revision("HEAD"))
+	if err != nil {
+		return ""
 	}
-	return ""
+	return hash.String()
 }
 
 // writeTmpKnownHosts creates a temporary file and writes known_hosts data to it, if such data is available from

internal/cmd/cli/apply_test.go

@@ -3,8 +3,13 @@ package cli
 import (
 	"errors"
 	"os"
+	"path/filepath"
+	"regexp"
 	"testing"
+	"time"
 
+	gogit "github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing/object"
 	"github.com/google/go-cmp/cmp"
 	"sigs.k8s.io/yaml"
 
@@ -226,3 +231,86 @@ func mockReadFile(name string) ([]byte, error) {
 
 	return nil, errorNotFound
 }
+
+func TestCurrentCommit(t *testing.T) {
+	t.Run("returns empty string for non-git directory", func(t *testing.T) {
+		dir := t.TempDir()
+		got := currentCommit(dir)
+		if got != "" {
+			t.Errorf("expected empty string for non-git dir, got %q", got)
+		}
+	})
+
+	t.Run("returns HEAD commit SHA for git repository", func(t *testing.T) {
+		dir := t.TempDir()
+
+		repo, err := gogit.PlainInit(dir, false)
+		if err != nil {
+			t.Fatalf("PlainInit: %v", err)
+		}
+		wt, err := repo.Worktree()
+		if err != nil {
+			t.Fatalf("Worktree: %v", err)
+		}
+
+		if err := os.WriteFile(filepath.Join(dir, "README"), []byte("test"), 0600); err != nil {
+			t.Fatalf("WriteFile: %v", err)
+		}
+		if _, err = wt.Add("README"); err != nil {
+			t.Fatalf("Add: %v", err)
+		}
+		expected, err := wt.Commit("initial commit", &gogit.CommitOptions{
+			Author: &object.Signature{Name: "test", Email: "test@example.com", When: time.Now()},
+		})
+		if err != nil {
+			t.Fatalf("Commit: %v", err)
+		}
+
+		got := currentCommit(dir)
+		if got != expected.String() {
+			t.Errorf("expected SHA %q, got %q", expected.String(), got)
+		}
+		if matched, _ := regexp.MatchString(`^[0-9a-f]{40}$`, got); !matched {
+			t.Errorf("expected a 40-char hex SHA, got %q", got)
+		}
+	})
+
+	t.Run("returns HEAD commit SHA from nested subdirectory", func(t *testing.T) {
+		dir := t.TempDir()
+
+		repo, err := gogit.PlainInit(dir, false)
+		if err != nil {
+			t.Fatalf("PlainInit: %v", err)
+		}
+		wt, err := repo.Worktree()
+		if err != nil {
+			t.Fatalf("Worktree: %v", err)
+		}
+
+		if err := os.WriteFile(filepath.Join(dir, "README"), []byte("test"), 0600); err != nil {
+			t.Fatalf("WriteFile: %v", err)
+		}
+		if _, err = wt.Add("README"); err != nil {
+			t.Fatalf("Add: %v", err)
+		}
+		expected, err := wt.Commit("initial commit", &gogit.CommitOptions{
+			Author: &object.Signature{Name: "test", Email: "test@example.com", When: time.Now()},
+		})
+		if err != nil {
+			t.Fatalf("Commit: %v", err)
+		}
+
+		subdir := filepath.Join(dir, "some", "nested")
+		if err := os.MkdirAll(subdir, 0o755); err != nil {
+			t.Fatalf("MkdirAll: %v", err)
+		}
+
+		got := currentCommit(subdir)
+		if got != expected.String() {
+			t.Errorf("expected SHA %q from nested subdir, got %q", expected.String(), got)
+		}
+		if matched, _ := regexp.MatchString(`^[0-9a-f]{40}$`, got); !matched {
+			t.Errorf("expected a 40-char hex SHA from nested subdir, got %q", got)
+		}
+	})
+}