format/commitgraph: Split into ./read and ./ v0.1.60

88 files changed, 99 insertions, 93 deletions

diff --git a/format/commitgraph/constants.go b/format/commitgraph/constants.go
index 96648fae..3a06a290 100644
--- a/format/commitgraph/constants.go
+++ b/format/commitgraph/constants.go
@@ -1,32 +1,32 @@
 package commitgraph
 
 const (
-	fileSignature = 0x43475048 // "CGPH"
-	fileVersion   = 1
+	FileSignature = 0x43475048 // "CGPH"
+	FileVersion   = 1
 )
 
 const (
-	chunkOIDF = 0x4f494446 // "OIDF"
-	chunkOIDL = 0x4f49444c // "OIDL"
-	chunkCDAT = 0x43444154 // "CDAT"
-	chunkGDA2 = 0x47444132 // "GDA2"
-	chunkGDO2 = 0x47444f32 // "GDO2"
-	chunkEDGE = 0x45444745 // "EDGE"
-	chunkBIDX = 0x42494458 // "BIDX"
-	chunkBDAT = 0x42444154 // "BDAT"
-	chunkBASE = 0x42415345 // "BASE"
+	ChunkOIDF = 0x4f494446 // "OIDF"
+	ChunkOIDL = 0x4f49444c // "OIDL"
+	ChunkCDAT = 0x43444154 // "CDAT"
+	ChunkGDA2 = 0x47444132 // "GDA2"
+	ChunkGDO2 = 0x47444f32 // "GDO2"
+	ChunkEDGE = 0x45444745 // "EDGE"
+	ChunkBIDX = 0x42494458 // "BIDX"
+	ChunkBDAT = 0x42444154 // "BDAT"
+	ChunkBASE = 0x42415345 // "BASE"
 )
 
 const (
-	headerSize     = 8
-	chunkEntrySize = 12
-	fanoutSize     = 256 * 4
+	HeaderSize     = 8
+	ChunkEntrySize = 12
+	FanoutSize     = 256 * 4
 )
 
 const (
-	parentNone      = 0x70000000
-	parentExtraMask = 0x80000000
-	parentLastMask  = 0x7fffffff
+	ParentNone      = 0x70000000
+	ParentExtraMask = 0x80000000
+	ParentLastMask  = 0x7fffffff
 
-	generationOverflow = 0x80000000
+	GenerationOverflow = 0x80000000
 )
diff --git a/format/commitgraph/bloom.go b/format/commitgraph/read/bloom.go
index 660dc1db..9b66f458 100644
--- a/format/commitgraph/bloom.go
+++ b/format/commitgraph/read/bloom.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"encoding/binary"
diff --git a/format/commitgraph/close.go b/format/commitgraph/read/close.go
index 8b9e2e9f..d91c7762 100644
--- a/format/commitgraph/close.go
+++ b/format/commitgraph/read/close.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 // Close releases all mapped commit-graph files.
 func (reader *Reader) Close() error {
diff --git a/format/commitgraph/commitat.go b/format/commitgraph/read/commitat.go
index 4d5853b1..bcd115f8 100644
--- a/format/commitgraph/commitat.go
+++ b/format/commitgraph/read/commitat.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"encoding/binary"
diff --git a/format/commitgraph/commits.go b/format/commitgraph/read/commits.go
index 0f5313e9..38dffe7b 100644
--- a/format/commitgraph/commits.go
+++ b/format/commitgraph/read/commits.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import "codeberg.org/lindenii/furgit/objectid"
 
diff --git a/format/commitgraph/edges.go b/format/commitgraph/read/edges.go
index 277735d0..de8bab60 100644
--- a/format/commitgraph/edges.go
+++ b/format/commitgraph/read/edges.go
@@ -1,8 +1,9 @@
-package commitgraph
+package read
 
 import (
 	"encoding/binary"
 
+	"codeberg.org/lindenii/furgit/format/commitgraph"
 	"codeberg.org/lindenii/furgit/internal/intconv"
 )
 
@@ -27,7 +28,7 @@ func (reader *Reader) decodeExtraEdgeList(layer *layer, edgeStart uint32) ([]Pos
 		}
 
 		word := binary.BigEndian.Uint32(layer.chunkExtraEdges[off : off+4])
-		parentGlobal := word & parentLastMask
+		parentGlobal := word & commitgraph.ParentLastMask
 
 		parentPos, err := reader.globalToPosition(parentGlobal)
 		if err != nil {
@@ -36,7 +37,7 @@ func (reader *Reader) decodeExtraEdgeList(layer *layer, edgeStart uint32) ([]Pos
 
 		out = append(out, parentPos)
 
-		if word&parentExtraMask != 0 {
+		if word&commitgraph.ParentExtraMask != 0 {
 			break
 		}
 
diff --git a/format/commitgraph/errors.go b/format/commitgraph/read/errors.go
index 0b7b7b6f..9d0eca04 100644
--- a/format/commitgraph/errors.go
+++ b/format/commitgraph/read/errors.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"fmt"
diff --git a/format/commitgraph/generation.go b/format/commitgraph/read/generation.go
index 41c743ab..d1f0ebe7 100644
--- a/format/commitgraph/generation.go
+++ b/format/commitgraph/read/generation.go
@@ -1,8 +1,9 @@
-package commitgraph
+package read
 
 import (
 	"encoding/binary"
 
+	"codeberg.org/lindenii/furgit/format/commitgraph"
 	"codeberg.org/lindenii/furgit/internal/intconv"
 )
 
@@ -20,11 +21,11 @@ func (reader *Reader) readGenerationV2(layer *layer, index uint32, commitTime ui
 
 	value := binary.BigEndian.Uint32(layer.chunkGeneration[off : off+4])
 
-	if value&generationOverflow == 0 {
+	if value&commitgraph.GenerationOverflow == 0 {
 		return commitTime + uint64(value), nil
 	}
 
-	gdo2Index := value ^ generationOverflow
+	gdo2Index := value ^ commitgraph.GenerationOverflow
 	gdo2Off64 := uint64(gdo2Index) * 8
 
 	gdo2Off, err := intconv.Uint64ToInt(gdo2Off64)
diff --git a/format/commitgraph/hash.go b/format/commitgraph/read/hash.go
index 55bc0195..3f30df91 100644
--- a/format/commitgraph/hash.go
+++ b/format/commitgraph/read/hash.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"bytes"
diff --git a/format/commitgraph/iterators.go b/format/commitgraph/read/iterators.go
index 27385709..d4ad9105 100644
--- a/format/commitgraph/iterators.go
+++ b/format/commitgraph/read/iterators.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"iter"
diff --git a/format/commitgraph/layer.go b/format/commitgraph/read/layer.go
index 3f6011cc..53ab1663 100644
--- a/format/commitgraph/layer.go
+++ b/format/commitgraph/read/layer.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"os"
diff --git a/format/commitgraph/layer_close.go b/format/commitgraph/read/layer_close.go
index 9b7dfbb0..03dc91d5 100644
--- a/format/commitgraph/layer_close.go
+++ b/format/commitgraph/read/layer_close.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import "syscall"
 
diff --git a/format/commitgraph/layer_lookup.go b/format/commitgraph/read/layer_lookup.go
index 3ae4ff53..9a03505a 100644
--- a/format/commitgraph/layer_lookup.go
+++ b/format/commitgraph/read/layer_lookup.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"bytes"
diff --git a/format/commitgraph/layer_open.go b/format/commitgraph/read/layer_open.go
index 857b3022..bf126960 100644
--- a/format/commitgraph/layer_open.go
+++ b/format/commitgraph/read/layer_open.go
@@ -1,9 +1,10 @@
-package commitgraph
+package read
 
 import (
 	"os"
 	"syscall"
 
+	"codeberg.org/lindenii/furgit/format/commitgraph"
 	"codeberg.org/lindenii/furgit/internal/intconv"
 	"codeberg.org/lindenii/furgit/objectid"
 )
@@ -22,7 +23,7 @@ func openLayer(root *os.Root, relPath string, algo objectid.Algorithm) (*layer,
 	}
 
 	size := info.Size()
-	if size < int64(headerSize+fanoutSize+algo.Size()) {
+	if size < int64(commitgraph.HeaderSize+commitgraph.FanoutSize+algo.Size()) {
 		_ = file.Close()
 
 		return nil, &ErrMalformed{Path: relPath, Reason: "file too short"}
diff --git a/format/commitgraph/layer_parse.go b/format/commitgraph/read/layer_parse.go
index d6d77b9e..dca9f416 100644
--- a/format/commitgraph/layer_parse.go
+++ b/format/commitgraph/read/layer_parse.go
@@ -1,27 +1,28 @@
-package commitgraph
+package read
 
 import (
 	"encoding/binary"
 
+	"codeberg.org/lindenii/furgit/format/commitgraph"
 	"codeberg.org/lindenii/furgit/format/commitgraph/bloom"
 	"codeberg.org/lindenii/furgit/internal/intconv"
 	"codeberg.org/lindenii/furgit/objectid"
 )
 
 func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
-	if len(layer.data) < headerSize {
+	if len(layer.data) < commitgraph.HeaderSize {
 		return &ErrMalformed{Path: layer.path, Reason: "file too short"}
 	}
 
-	header := layer.data[:headerSize]
+	header := layer.data[:commitgraph.HeaderSize]
 
 	signature := binary.BigEndian.Uint32(header[:4])
-	if signature != fileSignature {
+	if signature != commitgraph.FileSignature {
 		return &ErrMalformed{Path: layer.path, Reason: "invalid signature"}
 	}
 
 	version := header[4]
-	if version != fileVersion {
+	if version != commitgraph.FileVersion {
 		return &ErrUnsupportedVersion{Version: version}
 	}
 
@@ -38,8 +39,8 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 	numChunks := int(header[6])
 	baseCount := uint32(header[7])
 
-	tocLen := (numChunks + 1) * chunkEntrySize
-	tocStart := headerSize
+	tocLen := (numChunks + 1) * commitgraph.ChunkEntrySize
+	tocStart := commitgraph.HeaderSize
 
 	tocEnd := tocStart + tocLen
 	if tocEnd > len(layer.data) {
@@ -53,8 +54,8 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 
 	entries := make([]tocEntry, 0, numChunks+1)
 	for i := range numChunks + 1 {
-		entryOff := tocStart + i*chunkEntrySize
-		entryData := layer.data[entryOff : entryOff+chunkEntrySize]
+		entryOff := tocStart + i*commitgraph.ChunkEntrySize
+		entryData := layer.data[entryOff : entryOff+commitgraph.ChunkEntrySize]
 
 		entry := tocEntry{
 			id:     binary.BigEndian.Uint32(entryData[:4]),
@@ -99,13 +100,13 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		chunks[entry.id] = layer.data[start:end]
 	}
 
-	oidf := chunks[chunkOIDF]
-	if len(oidf) != fanoutSize {
+	oidf := chunks[commitgraph.ChunkOIDF]
+	if len(oidf) != commitgraph.FanoutSize {
 		return &ErrMalformed{Path: layer.path, Reason: "invalid OIDF length"}
 	}
 
 	layer.chunkOIDFanout = oidf
-	layer.numCommits = binary.BigEndian.Uint32(oidf[fanoutSize-4:])
+	layer.numCommits = binary.BigEndian.Uint32(oidf[commitgraph.FanoutSize-4:])
 
 	for i := range 255 {
 		cur := binary.BigEndian.Uint32(oidf[i*4 : (i+1)*4])
@@ -123,7 +124,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		return err
 	}
 
-	oidl := chunks[chunkOIDL]
+	oidl := chunks[commitgraph.ChunkOIDL]
 	oidlWantLen64 := uint64(layer.numCommits) * hashSizeU64
 
 	oidlWantLen, err := intconv.Uint64ToInt(oidlWantLen64)
@@ -144,7 +145,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		return err
 	}
 
-	cdat := chunks[chunkCDAT]
+	cdat := chunks[commitgraph.ChunkCDAT]
 	cdatWantLen64 := uint64(layer.numCommits) * strideU64
 
 	cdatWantLen, err := intconv.Uint64ToInt(cdatWantLen64)
@@ -158,7 +159,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 
 	layer.chunkCommit = cdat
 
-	gda2 := chunks[chunkGDA2]
+	gda2 := chunks[commitgraph.ChunkGDA2]
 	if len(gda2) != 0 {
 		wantLen64 := uint64(layer.numCommits) * 4
 
@@ -174,7 +175,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		layer.chunkGeneration = gda2
 	}
 
-	gdo2 := chunks[chunkGDO2]
+	gdo2 := chunks[commitgraph.ChunkGDO2]
 	if len(gdo2) != 0 {
 		if len(gdo2)%8 != 0 {
 			return &ErrMalformed{Path: layer.path, Reason: "invalid GDO2 length"}
@@ -183,7 +184,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		layer.chunkGenerationOv = gdo2
 	}
 
-	edge := chunks[chunkEDGE]
+	edge := chunks[commitgraph.ChunkEDGE]
 	if len(edge) != 0 {
 		if len(edge)%4 != 0 {
 			return &ErrMalformed{Path: layer.path, Reason: "invalid EDGE length"}
@@ -192,7 +193,7 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 		layer.chunkExtraEdges = edge
 	}
 
-	base := chunks[chunkBASE]
+	base := chunks[commitgraph.ChunkBASE]
 	if baseCount == 0 {
 		if len(base) != 0 {
 			return &ErrMalformed{Path: layer.path, Reason: "unexpected BASE chunk"}
@@ -214,9 +215,9 @@ func parseLayer(layer *layer, algo objectid.Algorithm) error { //nolint:maintidx
 
 	layer.baseCount = baseCount
 
-	bidx := chunks[chunkBIDX]
+	bidx := chunks[commitgraph.ChunkBIDX]
 
-	bdat := chunks[chunkBDAT]
+	bdat := chunks[commitgraph.ChunkBDAT]
 	if len(bidx) != 0 || len(bdat) != 0 { //nolint:nestif
 		if len(bidx) == 0 || len(bdat) == 0 {
 			return &ErrMalformed{Path: layer.path, Reason: "BIDX/BDAT must both be present"}
diff --git a/format/commitgraph/layer_pos.go b/format/commitgraph/read/layer_pos.go
index 3b82c433..b93a842e 100644
--- a/format/commitgraph/layer_pos.go
+++ b/format/commitgraph/read/layer_pos.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import "codeberg.org/lindenii/furgit/internal/intconv"
 
diff --git a/format/commitgraph/layerinfo.go b/format/commitgraph/read/layerinfo.go
index f5750368..83c4407d 100644
--- a/format/commitgraph/layerinfo.go
+++ b/format/commitgraph/read/layerinfo.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 // LayerInfo describes one loaded commit-graph layer.
 type LayerInfo struct {
diff --git a/format/commitgraph/lookup.go b/format/commitgraph/read/lookup.go
index 2cd8bf75..cfd3b8cc 100644
--- a/format/commitgraph/lookup.go
+++ b/format/commitgraph/read/lookup.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"codeberg.org/lindenii/furgit/internal/intconv"
diff --git a/format/commitgraph/mode.go b/format/commitgraph/read/mode.go
index 71b55412..76afa21f 100644
--- a/format/commitgraph/mode.go
+++ b/format/commitgraph/read/mode.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 // OpenMode controls which commit-graph layout Open loads.
 type OpenMode uint8
diff --git a/format/commitgraph/oidat.go b/format/commitgraph/read/oidat.go
index e277125b..af3f31f0 100644
--- a/format/commitgraph/oidat.go
+++ b/format/commitgraph/read/oidat.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"codeberg.org/lindenii/furgit/internal/intconv"
diff --git a/format/commitgraph/open.go b/format/commitgraph/read/open.go
index 5eff8934..2efb4b46 100644
--- a/format/commitgraph/open.go
+++ b/format/commitgraph/read/open.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"fmt"
diff --git a/format/commitgraph/open_chain.go b/format/commitgraph/read/open_chain.go
index 212a4049..f64040bc 100644
--- a/format/commitgraph/open_chain.go
+++ b/format/commitgraph/read/open_chain.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"bufio"
diff --git a/format/commitgraph/open_single.go b/format/commitgraph/read/open_single.go
index 255abf39..f20cd166 100644
--- a/format/commitgraph/open_single.go
+++ b/format/commitgraph/read/open_single.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"os"
diff --git a/format/commitgraph/parents.go b/format/commitgraph/read/parents.go
index df6d33ff..0f8024ab 100644
--- a/format/commitgraph/parents.go
+++ b/format/commitgraph/read/parents.go
@@ -1,4 +1,6 @@
-package commitgraph
+package read
+
+import "codeberg.org/lindenii/furgit/format/commitgraph"
 
 // ParentRef references one parent position.
 type ParentRef struct {
@@ -12,11 +14,11 @@ func (reader *Reader) decodeParents(layer *layer, p1, p2 uint32) (ParentRef, Par
 		return ParentRef{}, ParentRef{}, nil, err
 	}
 
-	if p2 == parentNone {
+	if p2 == commitgraph.ParentNone {
 		return parent1, ParentRef{}, nil, nil
 	}
 
-	if p2&parentExtraMask == 0 {
+	if p2&commitgraph.ParentExtraMask == 0 {
 		parent2, err := reader.decodeSingleParent(p2)
 		if err != nil {
 			return ParentRef{}, ParentRef{}, nil, err
@@ -25,7 +27,7 @@ func (reader *Reader) decodeParents(layer *layer, p1, p2 uint32) (ParentRef, Par
 		return parent1, parent2, nil, nil
 	}
 
-	edgeStart := p2 & parentLastMask
+	edgeStart := p2 & commitgraph.ParentLastMask
 
 	parents, err := reader.decodeExtraEdgeList(layer, edgeStart)
 	if err != nil {
@@ -45,11 +47,11 @@ func (reader *Reader) decodeParents(layer *layer, p1, p2 uint32) (ParentRef, Par
 }
 
 func (reader *Reader) decodeSingleParent(raw uint32) (ParentRef, error) {
-	if raw == parentNone {
+	if raw == commitgraph.ParentNone {
 		return ParentRef{}, nil
 	}
 
-	if raw&parentExtraMask != 0 {
+	if raw&commitgraph.ParentExtraMask != 0 {
 		return ParentRef{}, &ErrMalformed{
 			Path:   "commit-graph",
 			Reason: "unexpected EDGE marker in single-parent slot",
diff --git a/format/commitgraph/position.go b/format/commitgraph/read/position.go
index 5e8bd486..f92f5b3a 100644
--- a/format/commitgraph/position.go
+++ b/format/commitgraph/read/position.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import (
 	"fmt"
diff --git a/format/commitgraph/read_test.go b/format/commitgraph/read/read_test.go
index 0771514a..0efd67ca 100644
--- a/format/commitgraph/read_test.go
+++ b/format/commitgraph/read/read_test.go
@@ -1,4 +1,4 @@
-package commitgraph_test
+package read_test
 
 import (
 	"errors"
@@ -8,8 +8,8 @@ import (
 	"strings"
 	"testing"
 
-	"codeberg.org/lindenii/furgit/format/commitgraph"
 	"codeberg.org/lindenii/furgit/format/commitgraph/bloom"
+	"codeberg.org/lindenii/furgit/format/commitgraph/read"
 	"codeberg.org/lindenii/furgit/internal/intconv"
 	"codeberg.org/lindenii/furgit/internal/testgit"
 	"codeberg.org/lindenii/furgit/objectid"
@@ -33,7 +33,7 @@ func TestReadSingleMatchesGit(t *testing.T) {
 	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) { //nolint:thelper
 		testRepo := fixtureRepo(t, algo, "single_changed")
 
-		reader := openReader(t, testRepo, commitgraph.OpenSingle)
+		reader := openReader(t, testRepo, read.OpenSingle)
 
 		defer func() { _ = reader.Close() }()
 
@@ -97,7 +97,7 @@ func TestReadChainMatchesGit(t *testing.T) {
 	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) { //nolint:thelper
 		testRepo := fixtureRepo(t, algo, "chain_changed")
 
-		reader := openReader(t, testRepo, commitgraph.OpenChain)
+		reader := openReader(t, testRepo, read.OpenChain)
 
 		defer func() { _ = reader.Close() }()
 
@@ -150,7 +150,7 @@ func TestBloomUnavailableWithoutChangedPaths(t *testing.T) {
 	testgit.ForEachAlgorithm(t, func(t *testing.T, algo objectid.Algorithm) { //nolint:thelper
 		testRepo := fixtureRepo(t, algo, "single_nochanged")
 
-		reader := openReader(t, testRepo, commitgraph.OpenSingle)
+		reader := openReader(t, testRepo, read.OpenSingle)
 
 		defer func() { _ = reader.Close() }()
 
@@ -166,7 +166,7 @@ func TestBloomUnavailableWithoutChangedPaths(t *testing.T) {
 			t.Fatal("BloomFilterAt() error = nil, want ErrBloomUnavailable")
 		}
 
-		var unavailable *commitgraph.ErrBloomUnavailable
+		var unavailable *read.ErrBloomUnavailable
 		if !errors.As(err, &unavailable) {
 			t.Fatalf("BloomFilterAt() error type = %T, want *ErrBloomUnavailable", err)
 		}
@@ -177,7 +177,7 @@ func TestBloomUnavailableWithoutChangedPaths(t *testing.T) {
 	})
 }
 
-func openReader(tb testing.TB, testRepo *testgit.TestRepo, mode commitgraph.OpenMode) *commitgraph.Reader {
+func openReader(tb testing.TB, testRepo *testgit.TestRepo, mode read.OpenMode) *read.Reader {
 	tb.Helper()
 
 	objectsPath := filepath.Join(testRepo.Dir(), "objects")
@@ -187,7 +187,7 @@ func openReader(tb testing.TB, testRepo *testgit.TestRepo, mode commitgraph.Open
 		tb.Fatalf("os.OpenRoot(%q): %v", objectsPath, err)
 	}
 
-	reader, err := commitgraph.Open(root, testRepo.Algorithm(), mode)
+	reader, err := read.Open(root, testRepo.Algorithm(), mode)
 
 	closeErr := root.Close()
 	if closeErr != nil {
@@ -195,13 +195,13 @@ func openReader(tb testing.TB, testRepo *testgit.TestRepo, mode commitgraph.Open
 	}
 
 	if err != nil {
-		tb.Fatalf("commitgraph.Open(%q): %v", objectsPath, err)
+		tb.Fatalf("read.Open(%q): %v", objectsPath, err)
 	}
 
 	return reader
 }
 
-func verifyCommitAgainstGit(tb testing.TB, testRepo *testgit.TestRepo, reader *commitgraph.Reader, id objectid.ObjectID) {
+func verifyCommitAgainstGit(tb testing.TB, testRepo *testgit.TestRepo, reader *read.Reader, id objectid.ObjectID) {
 	tb.Helper()
 
 	pos, err := reader.Lookup(id)
@@ -265,7 +265,7 @@ func verifyCommitAgainstGit(tb testing.TB, testRepo *testgit.TestRepo, reader *c
 	assertChangedPathsBloomPositive(tb, testRepo, filter, id)
 }
 
-func commitParents(tb testing.TB, reader *commitgraph.Reader, commit commitgraph.Commit) []objectid.ObjectID {
+func commitParents(tb testing.TB, reader *read.Reader, commit read.Commit) []objectid.ObjectID {
 	tb.Helper()
 
 	out := make([]objectid.ObjectID, 0, 2+len(commit.ExtraParents))
diff --git a/format/commitgraph/reader.go b/format/commitgraph/read/reader.go
index b7af3282..922d459b 100644
--- a/format/commitgraph/reader.go
+++ b/format/commitgraph/read/reader.go
@@ -1,4 +1,4 @@
-package commitgraph
+package read
 
 import "codeberg.org/lindenii/furgit/objectid"
 
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/HEAD
index cb089cd8..cb089cd8 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/config
index 07d359d0..07d359d0 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
index 74c46b64..74c46b64 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-bf985c21612a52070d8b008e6ef51edf8b609401.graph b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-bf985c21612a52070d8b008e6ef51edf8b609401.graph
index c31869c1..c31869c1 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-bf985c21612a52070d8b008e6ef51edf8b609401.graph
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-bf985c21612a52070d8b008e6ef51edf8b609401.graph
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-dd7578d5216ca76c25b19631ba90f7498aeabbe7.graph b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-dd7578d5216ca76c25b19631ba90f7498aeabbe7.graph
index 241eb3cc..241eb3cc 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-dd7578d5216ca76c25b19631ba90f7498aeabbe7.graph
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/commit-graphs/graph-dd7578d5216ca76c25b19631ba90f7498aeabbe7.graph
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/packs
index 61decf9b..61decf9b 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.bitmap b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.bitmap
index 1508cf18..1508cf18 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.idx b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.idx
index 00ee2646..00ee2646 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.idx
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.pack b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.pack
index c65ae27f..c65ae27f 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.pack
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.rev b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.rev
index d0689f72..d0689f72 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/objects/pack/pack-15b064d6a8ef8cff520565f6db8c006b2e6f7f2f.rev
diff --git a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/refs/heads/master b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/refs/heads/master
index 8942d437..8942d437 100644
--- a/format/commitgraph/testdata/fixtures/sha1/chain_changed/repo.git/refs/heads/master
+++ b/format/commitgraph/read/testdata/fixtures/sha1/chain_changed/repo.git/refs/heads/master
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/HEAD
index b870d826..b870d826 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/config
index 07d359d0..07d359d0 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/info/commit-graph b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/info/commit-graph
index 56b59a54..56b59a54 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/info/commit-graph
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/info/commit-graph
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/info/packs
index ecf5d272..ecf5d272 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.bitmap b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.bitmap
index 9fec7b16..9fec7b16 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.idx b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.idx
index e30cbb5a..e30cbb5a 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.idx
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.pack b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.pack
index 8da45eab..8da45eab 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.pack
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.rev b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.rev
index 3bcd2e2c..3bcd2e2c 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/objects/pack/pack-34e9e132566989e2abfe8821731236c77f9bcbe9.rev
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/refs/heads/main b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/refs/heads/main
index 090ca933..090ca933 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_changed/repo.git/refs/heads/main
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_changed/repo.git/refs/heads/main
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/HEAD
index cb089cd8..cb089cd8 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/config
index 07d359d0..07d359d0 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/commit-graph b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/commit-graph
index 28f7d06a..28f7d06a 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/commit-graph
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/commit-graph
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/packs
index 8434a002..8434a002 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.bitmap b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.bitmap
index 64a36c71..64a36c71 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.idx b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.idx
index f5e16674..f5e16674 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.idx
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.pack b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.pack
index 8f82b451..8f82b451 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.pack
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.rev b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.rev
index 64771f70..64771f70 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/objects/pack/pack-a3da595034c94bb16b6829d757a66b7d259b9ffc.rev
diff --git a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/refs/heads/master b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/refs/heads/master
index 475cb2c1..475cb2c1 100644
--- a/format/commitgraph/testdata/fixtures/sha1/single_nochanged/repo.git/refs/heads/master
+++ b/format/commitgraph/read/testdata/fixtures/sha1/single_nochanged/repo.git/refs/heads/master
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/HEAD
index cb089cd8..cb089cd8 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/config
index 7d1c0006..7d1c0006 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
index 4e7d76fe..4e7d76fe 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/commit-graph-chain
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-505cab61f8ddfa614301e8f97943112739236c6bcd19ed4d1f7c6b830cab4f62.graph b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-505cab61f8ddfa614301e8f97943112739236c6bcd19ed4d1f7c6b830cab4f62.graph
index 4a93de94..4a93de94 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-505cab61f8ddfa614301e8f97943112739236c6bcd19ed4d1f7c6b830cab4f62.graph
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-505cab61f8ddfa614301e8f97943112739236c6bcd19ed4d1f7c6b830cab4f62.graph
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-77c47bd6ca2ce17208c9361717a5823c0cb4b5ee336a14959678e060d674ffb6.graph b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-77c47bd6ca2ce17208c9361717a5823c0cb4b5ee336a14959678e060d674ffb6.graph
index 7807351d..7807351d 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-77c47bd6ca2ce17208c9361717a5823c0cb4b5ee336a14959678e060d674ffb6.graph
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/commit-graphs/graph-77c47bd6ca2ce17208c9361717a5823c0cb4b5ee336a14959678e060d674ffb6.graph
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/packs
index 3b1241c4..3b1241c4 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.bitmap b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.bitmap
index 007fcd0e..007fcd0e 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.idx b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.idx
index 248cf8fc..248cf8fc 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.idx
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.pack b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.pack
index 92cea7fb..92cea7fb 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.pack
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.rev b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.rev
index 569862ce..569862ce 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/objects/pack/pack-04168d0884c910f505cb9fbcf045957e44ccee06d812b5e531ae666014a26ed1.rev
diff --git a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/refs/heads/master b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/refs/heads/master
index 29d83be8..29d83be8 100644
--- a/format/commitgraph/testdata/fixtures/sha256/chain_changed/repo.git/refs/heads/master
+++ b/format/commitgraph/read/testdata/fixtures/sha256/chain_changed/repo.git/refs/heads/master
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/HEAD
index b870d826..b870d826 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/config
index 7d1c0006..7d1c0006 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/info/commit-graph b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/info/commit-graph
index f4dd0e0c..f4dd0e0c 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/info/commit-graph
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/info/commit-graph
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/info/packs
index 0f39ed89..0f39ed89 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.bitmap b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.bitmap
index b5c5055c..b5c5055c 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.idx b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.idx
index 144778cd..144778cd 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.idx
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.pack b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.pack
index 599ccae0..599ccae0 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.pack
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.rev b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.rev
index 3c093f31..3c093f31 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/objects/pack/pack-316dbc67dac12d131591640da0c55b76387cbf1fd2a117ab3d7ca0d854a031c9.rev
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/refs/heads/main b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/refs/heads/main
index 4ba32358..4ba32358 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_changed/repo.git/refs/heads/main
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_changed/repo.git/refs/heads/main
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/HEAD b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/HEAD
index cb089cd8..cb089cd8 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/HEAD
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/HEAD
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/config b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/config
index 7d1c0006..7d1c0006 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/config
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/config
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/commit-graph b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/commit-graph
index f98ca4a1..f98ca4a1 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/commit-graph
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/commit-graph
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/packs b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/packs
index 65184c9a..65184c9a 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/packs
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/info/packs
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.bitmap b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.bitmap
index 53530f4c..53530f4c 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.bitmap
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.bitmap
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.idx b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.idx
index b3a417a8..b3a417a8 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.idx
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.idx
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.pack b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.pack
index d8dcedbf..d8dcedbf 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.pack
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.pack
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.rev b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.rev
index e50d1a81..e50d1a81 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.rev
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/objects/pack/pack-d335453f760b064e36459d780ec9bf0e5dd596c0ee1ac6310136067c4f13438b.rev
diff --git a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/refs/heads/master b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/refs/heads/master
index a4e184b4..a4e184b4 100644
--- a/format/commitgraph/testdata/fixtures/sha256/single_nochanged/repo.git/refs/heads/master
+++ b/format/commitgraph/read/testdata/fixtures/sha256/single_nochanged/repo.git/refs/heads/master
diff --git a/reachability/ancestor.go b/reachability/ancestor.go
index 5c978bf4..98a2c080 100644
--- a/reachability/ancestor.go
+++ b/reachability/ancestor.go
@@ -3,7 +3,7 @@ package reachability
 import (
 	"errors"
 
-	"codeberg.org/lindenii/furgit/format/commitgraph"
+	commitgraphread "codeberg.org/lindenii/furgit/format/commitgraph/read"
 	"codeberg.org/lindenii/furgit/objectid"
 )
 
@@ -57,7 +57,7 @@ func (r *Reachability) isAncestorGraph(ancestor, descendant objectid.ObjectID) (
 
 	ancestorPos, err := r.graph.Lookup(ancestor)
 	if err != nil {
-		var notFound *commitgraph.ErrNotFound
+		var notFound *commitgraphread.ErrNotFound
 		if errors.As(err, &notFound) {
 			return false, false, nil
 		}
@@ -67,7 +67,7 @@ func (r *Reachability) isAncestorGraph(ancestor, descendant objectid.ObjectID) (
 
 	descendantPos, err := r.graph.Lookup(descendant)
 	if err != nil {
-		var notFound *commitgraph.ErrNotFound
+		var notFound *commitgraphread.ErrNotFound
 		if errors.As(err, &notFound) {
 			return false, false, nil
 		}
@@ -81,8 +81,8 @@ func (r *Reachability) isAncestorGraph(ancestor, descendant objectid.ObjectID) (
 	}
 
 	ancestorGeneration := ancestorCommit.GenerationV2
-	stack := []commitgraph.Position{descendantPos}
-	visited := make(map[commitgraph.Position]struct{}, 64)
+	stack := []commitgraphread.Position{descendantPos}
+	visited := make(map[commitgraphread.Position]struct{}, 64)
 
 	for len(stack) > 0 {
 		pos := stack[len(stack)-1]
diff --git a/reachability/reachability.go b/reachability/reachability.go
index 1180e32a..f9dab764 100644
--- a/reachability/reachability.go
+++ b/reachability/reachability.go
@@ -2,7 +2,7 @@
 package reachability
 
 import (
-	"codeberg.org/lindenii/furgit/format/commitgraph"
+	commitgraphread "codeberg.org/lindenii/furgit/format/commitgraph/read"
 	"codeberg.org/lindenii/furgit/objectstore"
 )
 
@@ -11,7 +11,7 @@ import (
 // It is not safe for concurrent use.
 type Reachability struct {
 	store objectstore.Store
-	graph *commitgraph.Reader
+	graph *commitgraphread.Reader
 }
 
 // New builds a Reachability  over one object store.
@@ -21,6 +21,6 @@ func New(store objectstore.Store) *Reachability {
 
 // NewWithCommitGraph builds a Reachability over one object store with an
 // optional commit-graph reader for faster commit-domain traversal.
-func NewWithCommitGraph(store objectstore.Store, graph *commitgraph.Reader) *Reachability {
+func NewWithCommitGraph(store objectstore.Store, graph *commitgraphread.Reader) *Reachability {
 	return &Reachability{store: store, graph: graph}
 }
diff --git a/reachability/walk_expand_commits_graph.go b/reachability/walk_expand_commits_graph.go
index 15780c8e..bbdc0ade 100644
--- a/reachability/walk_expand_commits_graph.go
+++ b/reachability/walk_expand_commits_graph.go
@@ -3,7 +3,7 @@ package reachability
 import (
 	"errors"
 
-	"codeberg.org/lindenii/furgit/format/commitgraph"
+	commitgraphread "codeberg.org/lindenii/furgit/format/commitgraph/read"
 	"codeberg.org/lindenii/furgit/objectid"
 	"codeberg.org/lindenii/furgit/objecttype"
 )
@@ -11,7 +11,7 @@ import (
 func (walk *Walk) expandCommitsFromGraph(id objectid.ObjectID) ([]walkItem, bool, error) {
 	pos, err := walk.reachability.graph.Lookup(id)
 	if err != nil {
-		var notFound *commitgraph.ErrNotFound
+		var notFound *commitgraphread.ErrNotFound
 		if errors.As(err, &notFound) {
 			return nil, false, nil
 		}