Urgh I made some wrong amends and I'm too tired to separate the commits out this time

ancestor: Split out of reachability
mergebase: Add merge base routines
internal/commitquery: Add commit query context engine thingy
internal/peel: Shared tag peeling
errors: Shared object query errors
internal/testgit: Add rooted repo helpers; remove raw path access
objectstore/memory: Add in-memory object store
objectid: Add Compare helper

1 files changed, 39 insertions, 0 deletions

diff --git a/internal/commitquery/node.go b/internal/commitquery/node.go
new file mode 100644
index 00000000..7abf381d
--- /dev/null
+++ b/internal/commitquery/node.go
@@ -0,0 +1,39 @@
+package commitquery
+
+import (
+	commitgraphread "codeberg.org/lindenii/furgit/format/commitgraph/read"
+	"codeberg.org/lindenii/furgit/objectid"
+)
+
+// NodeIndex identifies one internal query node.
+type NodeIndex int
+
+// node stores one mutable commit traversal node.
+type node struct {
+	id objectid.ObjectID
+
+	parents []NodeIndex
+
+	commitTime int64
+	generation uint64
+
+	hasGeneration bool
+	hasGraphPos   bool
+	loaded        bool
+
+	graphPos commitgraphread.Position
+	marks    markBits
+
+	touchedPhase uint32
+}
+
+// newNode allocates one empty internal node.
+func (ctx *Context) newNode(id objectid.ObjectID) NodeIndex {
+	count := len(ctx.nodes)
+
+	idx := NodeIndex(count)
+
+	ctx.nodes = append(ctx.nodes, node{id: id})
+
+	return idx
+}