plumbing: format/commitgraph, add APIs for reading and writing commit-graph files

Signed-off-by: Filip Navara <filip.navara@gmail.com>

1 files changed, 35 insertions, 0 deletions

diff --git a/plumbing/format/commitgraph/commitgraph.go b/plumbing/format/commitgraph/commitgraph.go
new file mode 100644
index 0000000..9bf7149
--- /dev/null
+++ b/plumbing/format/commitgraph/commitgraph.go
@@ -0,0 +1,35 @@
+package commitgraph

+

+import (

+	"time"

+

+	"gopkg.in/src-d/go-git.v4/plumbing"

+)

+

+// Node is a reduced representation of Commit as presented in the commit graph

+// file. It is merely useful as an optimization for walking the commit graphs.

+type Node struct {

+	// TreeHash is the hash of the root tree of the commit.

+	TreeHash plumbing.Hash

+	// ParentIndexes are the indexes of the parent commits of the commit.

+	ParentIndexes []int

+	// ParentHashes are the hashes of the parent commits of the commit.

+	ParentHashes []plumbing.Hash

+	// Generation number is the pre-computed generation in the commit graph

+	// or zero if not available

+	Generation int

+	// When is the timestamp of the commit.

+	When time.Time

+}

+

+// Index represents a representation of commit graph that allows indexed

+// access to the nodes using commit object hash

+type Index interface {

+	// GetIndexByHash gets the index in the commit graph from commit hash, if available

+	GetIndexByHash(h plumbing.Hash) (int, error)

+	// GetNodeByIndex gets the commit node from the commit graph using index

+	// obtained from child node, if available

+	GetNodeByIndex(i int) (*Node, error)

+	// Hashes returns all the hashes that are available in the index

+	Hashes() []plumbing.Hash

+}