format/commitgraph: Add initial commit-graph support

1 files changed, 45 insertions, 0 deletions

diff --git a/format/commitgraph/iterators.go b/format/commitgraph/iterators.go
new file mode 100644
index 00000000..27385709
--- /dev/null
+++ b/format/commitgraph/iterators.go
@@ -0,0 +1,45 @@
+package commitgraph
+
+import (
+	"iter"
+
+	"codeberg.org/lindenii/furgit/internal/intconv"
+	"codeberg.org/lindenii/furgit/objectid"
+)
+
+// AllPositions iterates all commit positions in native layer order.
+func (reader *Reader) AllPositions() iter.Seq[Position] {
+	return func(yield func(Position) bool) {
+		for layerIdx := range reader.layers {
+			layer := &reader.layers[layerIdx]
+
+			graph, err := intconv.IntToUint32(layerIdx)
+			if err != nil {
+				return
+			}
+
+			for idx := range layer.numCommits {
+				if !yield(Position{Graph: graph, Index: idx}) {
+					return
+				}
+			}
+		}
+	}
+}
+
+// AllOIDs iterates all commit object IDs in native layer order.
+func (reader *Reader) AllOIDs() iter.Seq[objectid.ObjectID] {
+	return func(yield func(objectid.ObjectID) bool) {
+		positions := reader.AllPositions()
+		for pos := range positions {
+			oid, err := reader.OIDAt(pos)
+			if err != nil {
+				return
+			}
+
+			if !yield(oid) {
+				return
+			}
+		}
+	}
+}