git: Provide function to get hex-encoded length of object hashes

Many of our tests will require the ability to tell how long the current
object hash is supposed to be in its hex-encoded length. Add a new
function `EncodedLen()` that returns this information.

2 files changed, 11 insertions, 0 deletions

diff --git a/internal/git/object_id.go b/internal/git/object_id.go
index 88db74d44..2826215d3 100644
--- a/internal/git/object_id.go
+++ b/internal/git/object_id.go
@@ -71,6 +71,11 @@ func DetectObjectHash(ctx context.Context, repoExecutor RepositoryExecutor) (Obj
 	}
 }
 
+// EncodedLen returns the length of the hex-encoded string of a full object ID.
+func (h ObjectHash) EncodedLen() int {
+	return hex.EncodedLen(h.Hash().Size())
+}
+
 // FromHex constructs a new ObjectID from the given hex representation of the object ID. Returns
 // ErrInvalidObjectID if the given object ID is not valid.
 func (h ObjectHash) FromHex(hex string) (ObjectID, error) {
diff --git a/internal/git/object_id_test.go b/internal/git/object_id_test.go
index 44ac98a46..8c8502ef4 100644
--- a/internal/git/object_id_test.go
+++ b/internal/git/object_id_test.go
@@ -267,6 +267,12 @@ func TestObjectHash_FromHex(t *testing.T) {
 	}
 }
 
+func TestObjectHash_EncodedLen(t *testing.T) {
+	t.Parallel()
+	require.Equal(t, 40, git.ObjectHashSHA1.EncodedLen())
+	require.Equal(t, 64, git.ObjectHashSHA256.EncodedLen())
+}
+
 func TestObjectID_Bytes(t *testing.T) {
 	for _, tc := range []struct {
 		desc          string