1 files changed, 184 insertions, 0 deletions
diff --git a/object/id/objectid_test.go b/object/id/objectid_test.go
new file mode 100644
index 00000000..2559be0a
--- /dev/null
+++ b/object/id/objectid_test.go
@@ -0,0 +1,184 @@
+package objectid_test
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+
+	objectid "codeberg.org/lindenii/furgit/object/id"
+)
+
+func TestParseAlgorithm(t *testing.T) {
+	t.Parallel()
+
+	algo, ok := objectid.ParseAlgorithm("sha1")
+	if !ok || algo != objectid.AlgorithmSHA1 {
+		t.Fatalf("ParseAlgorithm(sha1) = (%v,%v)", algo, ok)
+	}
+
+	algo, ok = objectid.ParseAlgorithm("sha256")
+	if !ok || algo != objectid.AlgorithmSHA256 {
+		t.Fatalf("ParseAlgorithm(sha256) = (%v,%v)", algo, ok)
+	}
+
+	if _, ok := objectid.ParseAlgorithm("md5"); ok {
+		t.Fatalf("ParseAlgorithm(md5) should fail")
+	}
+}
+
+func TestParseHexRoundtrip(t *testing.T) {
+	t.Parallel()
+
+	for _, algo := range objectid.SupportedAlgorithms() {
+		t.Run(algo.String(), func(t *testing.T) {
+			t.Parallel()
+
+			hex := strings.Repeat("01", algo.Size())
+
+			id, err := objectid.ParseHex(algo, hex)
+			if err != nil {
+				t.Fatalf("ParseHex failed: %v", err)
+			}
+
+			if got := id.String(); got != hex {
+				t.Fatalf("String() = %q, want %q", got, hex)
+			}
+
+			if got := id.Size(); got != algo.Size() {
+				t.Fatalf("Size() = %d, want %d", got, algo.Size())
+			}
+
+			raw := id.Bytes()
+			if len(raw) != algo.Size() {
+				t.Fatalf("Bytes len = %d, want %d", len(raw), algo.Size())
+			}
+
+			id2, err := objectid.FromBytes(algo, raw)
+			if err != nil {
+				t.Fatalf("FromBytes failed: %v", err)
+			}
+
+			if id2.String() != hex {
+				t.Fatalf("FromBytes roundtrip = %q, want %q", id2.String(), hex)
+			}
+		})
+	}
+}
+
+func TestParseHexErrors(t *testing.T) {
+	t.Parallel()
+
+	t.Run("unknown algo", func(t *testing.T) {
+		t.Parallel()
+
+		_, err := objectid.ParseHex(objectid.AlgorithmUnknown, "00")
+		if err == nil {
+			t.Fatalf("expected ParseHex error")
+		}
+	})
+
+	for _, algo := range objectid.SupportedAlgorithms() {
+		t.Run(algo.String(), func(t *testing.T) {
+			t.Parallel()
+
+			_, err := objectid.ParseHex(algo, strings.Repeat("0", algo.HexLen()-1))
+			if err == nil {
+				t.Fatalf("expected ParseHex odd-len error")
+			}
+
+			_, err = objectid.ParseHex(algo, strings.Repeat("0", algo.HexLen()-2))
+			if err == nil {
+				t.Fatalf("expected ParseHex wrong-len error")
+			}
+
+			_, err = objectid.ParseHex(algo, "z"+strings.Repeat("0", algo.HexLen()-1))
+			if err == nil {
+				t.Fatalf("expected ParseHex invalid-hex error")
+			}
+		})
+	}
+}
+
+func TestFromBytesErrors(t *testing.T) {
+	t.Parallel()
+
+	_, err := objectid.FromBytes(objectid.AlgorithmUnknown, []byte{1, 2})
+	if err == nil {
+		t.Fatalf("expected FromBytes unknown algo error")
+	}
+
+	for _, algo := range objectid.SupportedAlgorithms() {
+		_, err = objectid.FromBytes(algo, []byte{1, 2})
+		if err == nil {
+			t.Fatalf("expected FromBytes wrong size error")
+		}
+	}
+}
+
+func TestBytesReturnsCopy(t *testing.T) {
+	t.Parallel()
+
+	for _, algo := range objectid.SupportedAlgorithms() {
+		id, err := objectid.ParseHex(algo, strings.Repeat("01", algo.Size()))
+		if err != nil {
+			t.Fatalf("ParseHex failed: %v", err)
+		}
+
+		b1 := id.Bytes()
+
+		b2 := id.Bytes()
+		if !bytes.Equal(b1, b2) {
+			t.Fatalf("Bytes mismatch")
+		}
+
+		b1[0] ^= 0xff
+		if bytes.Equal(b1, b2) {
+			t.Fatalf("Bytes should return independent copies")
+		}
+	}
+}
+
+func TestRawBytesAliasesStorage(t *testing.T) {
+	t.Parallel()
+
+	for _, algo := range objectid.SupportedAlgorithms() {
+		id, err := objectid.ParseHex(algo, strings.Repeat("01", algo.Size()))
+		if err != nil {
+			t.Fatalf("ParseHex failed: %v", err)
+		}
+
+		b := id.RawBytes()
+		if len(b) != id.Size() {
+			t.Fatalf("RawBytes len = %d, want %d", len(b), id.Size())
+		}
+
+		if cap(b) != len(b) {
+			t.Fatalf("RawBytes cap = %d, want %d", cap(b), len(b))
+		}
+
+		orig := id.String()
+		b[0] ^= 0xff
+
+		if id.String() == orig {
+			t.Fatalf("RawBytes should alias object ID storage")
+		}
+	}
+}
+
+func TestAlgorithmSum(t *testing.T) {
+	t.Parallel()
+
+	id1 := objectid.AlgorithmSHA1.Sum([]byte("hello"))
+	if id1.Algorithm() != objectid.AlgorithmSHA1 || id1.Size() != objectid.AlgorithmSHA1.Size() {
+		t.Fatalf("sha1 sum produced invalid object id")
+	}
+
+	id2 := objectid.AlgorithmSHA256.Sum([]byte("hello"))
+	if id2.Algorithm() != objectid.AlgorithmSHA256 || id2.Size() != objectid.AlgorithmSHA256.Size() {
+		t.Fatalf("sha256 sum produced invalid object id")
+	}
+
+	if id1.String() == id2.String() {
+		t.Fatalf("sha1 and sha256 should differ")
+	}
+}