fix a problem with deleted files

pkg/floatingversion/floatingversion_test.go

@@ -14,7 +14,7 @@
  * language governing permissions and limitations under the License.
  */
 
-package floatingversion
+package floatingversion_test
 
 import (
 	"errors"
@@ -30,6 +30,8 @@ import (
 	"github.com/go-git/go-git/v5/storage/memory"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+
+	"github.com/0x5a17ed/semverkzeug/pkg/floatingversion"
 )
 
 var signature = &object.Signature{
@@ -79,6 +81,24 @@ func oneCommitFixture(t *testing.T) (billy.Filesystem, *git.Repository) {
 	return fs, repo
 }
 
+func oneCommitFileDeletedFixture(t *testing.T) (billy.Filesystem, *git.Repository) {
+	fs, repo := emptyDirtyFixture(t)
+
+	wt, err := repo.Worktree()
+	require.NoError(t, err)
+
+	err = wt.AddWithOptions(&git.AddOptions{Path: "foo"})
+	require.NoError(t, err)
+
+	_, err = wt.Commit("asd", &git.CommitOptions{Author: signature, Committer: signature})
+	require.NoError(t, err)
+
+	err = fs.Remove("/foo")
+	require.NoError(t, err)
+
+	return fs, repo
+}
+
 func oneCommitDirtyFixture(t *testing.T) (billy.Filesystem, *git.Repository) {
 	fs, repo := oneCommitFixture(t)
 
@@ -145,6 +165,7 @@ func TestGetVersion(t *testing.T) {
 		{"empty-dirty", emptyDirtyFixture, `v0\.0\.1-dev\.0\.\d{14}`, assert.NoError},
 		{"one-commit-no-tag", oneCommitFixture, `v0\.0\.1-dev\.1`, assert.NoError},
 		{"one-commit-no-tag-dirty", oneCommitDirtyFixture, `v0\.0\.1-dev\.1\.\d{14}`, assert.NoError},
+		{"one-commit-no-tag-deleted-file", oneCommitFileDeletedFixture, `v0\.0\.1-dev\.1\.\d{14}`, assert.NoError},
 		{"one-tag", oneTaggedCommitRepositoryFixture, `v0\.1\.0`, assert.NoError},
 		{"one-tag-dirty", oneTaggedDirtyFixture, `v0\.1\.1-dev\.0\.\d{14}`, assert.NoError},
 		{"one-tag-one-commit", oneTagOneCommitFixture, `v0\.1\.1-dev\.1`, assert.NoError},
@@ -159,7 +180,7 @@ func TestGetVersion(t *testing.T) {
 				require.NoError(t, err)
 			}
 
-			gotVs, err := Get(repo, head, false)
+			gotVs, err := floatingversion.Get(repo, head, false)
 			if !tt.wantErr(t, err, fmt.Sprintf("Get(%v)", tt.repo)) {
 				return
 			}

pkg/gitversions/lastmodtime.go

@@ -18,29 +18,46 @@ package gitversions
 
 import (
 	"errors"
+	"io/fs"
+	"path/filepath"
 	"time"
 
+	"github.com/go-git/go-billy/v5"
 	"github.com/go-git/go-git/v5"
 )
 
 var (
 	ErrNotDirty = errors.New("repository is clean")
 )
 
+func findModTime(vfs billy.Filesystem, fp string) (time.Time, error) {
+	for {
+		fi, err := vfs.Lstat(fp)
+		if err != nil {
+			if errors.Is(err, fs.ErrNotExist) && fp != "." {
+				// File was probably deleted. Try parent directory.
+				fp = filepath.Dir(fp)
+				continue
+			}
+			return time.Time{}, err
+		}
+		return fi.ModTime().UTC(), nil
+	}
+}
+
 func LastModificationTime(wt *git.Worktree, st git.Status) (*time.Time, error) {
 	var latestChange time.Time
 
-	for fp, fs := range st {
-		if fs.Worktree == git.Unmodified && fs.Staging == git.Unmodified {
+	for fp, fst := range st {
+		if fst.Worktree == git.Unmodified && fst.Staging == git.Unmodified {
 			continue
 		}
 
-		if fi, err := wt.Filesystem.Lstat(fp); err == nil {
-			if mtime := fi.ModTime(); mtime.After(latestChange) {
-				latestChange = mtime.UTC()
-			}
-		} else {
+		switch mtime, err := findModTime(wt.Filesystem, fp); {
+		case err != nil:
 			return nil, err
+		case mtime.After(latestChange):
+			latestChange = mtime
 		}
 	}