Add sha256 object format support

Makefile

@@ -2,12 +2,15 @@
 
 vet:
 	go vet
+	go vet -tags test_sha256
 
 test:
 	go test -v -cover -race
+	go test -tags test_sha256 -v -cover -race
 
 bench:
 	go test -v -cover -test.bench=. -test.benchmem
 
 coverage:
 	go test -coverprofile=c.out && go tool cover -html=c.out && rm c.out
+	go test -tags test_sha256 -coverprofile=c.out && go tool cover -html=c.out && rm c.out

blob_test.go

@@ -31,7 +31,7 @@ This demo also includes an image with changes on a branch for examination of ima
 		TreeEntry: &TreeEntry{
 			mode: EntryBlob,
 			typ:  ObjectBlob,
-			id:   MustIDFromString("adfd6da3c0a3fb038393144becbf37f14f780087"), // Blob ID of "README.txt" file
+			id:   testrepoMarks[39], // Blob ID of "README.txt" file
 			parent: &Tree{
 				repo: testrepo,
 			},

commit.go

@@ -11,16 +11,16 @@ import (
 
 // Commit contains information of a Git commit.
 type Commit struct {
-	// The SHA-1 hash of the commit.
-	ID *SHA1
+	// The hash of the commit.
+	ID Oid
 	//  The author of the commit.
 	Author *Signature
 	// The committer of the commit.
 	Committer *Signature
 	// The full commit message.
 	Message string
 
-	parents []*SHA1
+	parents []Oid
 	*Tree
 
 	submodules    Submodules
@@ -39,9 +39,9 @@ func (c *Commit) ParentsCount() int {
 	return len(c.parents)
 }
 
-// ParentID returns the SHA-1 hash of the n-th parent (0-based) of this commit.
+// ParentID returns the Oid of the n-th parent (0-based) of this commit.
 // It returns an ErrParentNotExist if no such parent exists.
-func (c *Commit) ParentID(n int) (*SHA1, error) {
+func (c *Commit) ParentID(n int) (Oid, error) {
 	if n >= len(c.parents) {
 		return nil, ErrParentNotExist
 	}

commit_archive_test.go

@@ -22,7 +22,7 @@ func TestCommit_Archive(t *testing.T) {
 		ArchiveTarGz,
 	} {
 		t.Run(string(format), func(t *testing.T) {
-			c, err := testrepo.CatFileCommit(ctx, "755fd577edcfd9209d0ac072eed3b022cbe4d39b")
+			c, err := testrepo.CatFileCommit(ctx, testrepoMarks[1].String())
 			if err != nil {
 				t.Fatal(err)
 			}

commit_submodule_test.go

@@ -10,7 +10,7 @@ import (
 func TestCommit_Submodule(t *testing.T) {
 	ctx := context.Background()
 
-	c, err := testrepo.CatFileCommit(ctx, "4e59b72440188e7c2578299fc28ea425fbe9aece")
+	c, err := testrepo.CatFileCommit(ctx, testrepoMarks[29].String())
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -21,7 +21,7 @@ func TestCommit_Submodule(t *testing.T) {
 	}
 	assert.Equal(t, "gogs/docs-api", mod.Name)
 	assert.Equal(t, "https://github.com/gogs/docs-api.git", mod.URL)
-	assert.Equal(t, "6b08f76a5313fa3d26859515b30aa17a5faa2807", mod.Commit)
+	assert.Equal(t, submoduleSHA.String(), mod.Commit)
 
 	_, err = c.Submodule(ctx, "404")
 	assert.Equal(t, ErrSubmoduleNotExist, err)