ref: f762271dbfc121eaac7eb59c0beb01620a09118f
dir: /commitgraph_read_test.go/
package furgit
import (
"bytes"
"encoding/binary"
"fmt"
"os"
"path/filepath"
"sort"
"strconv"
"strings"
"testing"
"codeberg.org/lindenii/furgit/internal/bloom"
)
func TestCommitGraphReadBasic(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
workDir, cleanupWork := setupWorkDir(t)
defer cleanupWork()
files := []string{"a.txt", "b.txt", "c.txt"}
for i, name := range files {
path := filepath.Join(workDir, name)
content := fmt.Sprintf("content-%d\n", i)
if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
t.Fatalf("write %s: %v", name, err)
}
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "add", ".")
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "commit", "-m", fmt.Sprintf("commit %d", i))
}
gitCmd(t, repoPath, nil, "repack", "-a", "-d")
gitCmd(t, repoPath, nil, "commit-graph", "write", "--reachable", "--changed-paths")
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
cg, err := repo.CommitGraph()
if err != nil {
t.Fatalf("CommitGraph failed: %v", err)
}
revList := gitCmd(t, repoPath, nil, "rev-list", "--all")
commits := strings.Fields(revList)
if len(commits) == 0 {
t.Fatal("no commits found")
}
falsePositives := 0
for _, oidStr := range commits {
id, err := repo.ParseHash(oidStr)
if err != nil {
t.Fatalf("ParseHash failed: %v", err)
}
pos, ok := cg.CommitPosition(id)
if !ok {
t.Fatalf("commit %s not found in commit-graph", oidStr)
}
cc, err := cg.CommitAt(pos)
if err != nil {
t.Fatalf("CommitAt failed: %v", err)
}
treeStr := string(gitCmd(t, repoPath, nil, "show", "-s", "--format=%T", oidStr))
tree, err := repo.ParseHash(treeStr)
if err != nil {
t.Fatalf("ParseHash tree failed: %v", err)
}
if cc.Tree != tree {
t.Fatalf("tree mismatch for %s: got %s want %s", oidStr, cc.Tree.String(), tree.String())
}
parentStr := string(gitCmd(t, repoPath, nil, "show", "-s", "--format=%P", oidStr))
parents := strings.Fields(parentStr)
if len(parents) != len(cc.Parents) {
t.Fatalf("parent count mismatch for %s: got %d want %d", oidStr, len(cc.Parents), len(parents))
}
for i, p := range parents {
pid, err := repo.ParseHash(p)
if err != nil {
t.Fatalf("ParseHash parent failed: %v", err)
}
got, err := cg.OIDAt(cc.Parents[i])
if err != nil {
t.Fatalf("OIDAt parent failed: %v", err)
}
if got != pid {
t.Fatalf("parent mismatch for %s: got %s want %s", oidStr, got.String(), pid.String())
}
}
ctStr := gitCmd(t, repoPath, nil, "show", "-s", "--format=%ct", oidStr)
ct, err := strconv.ParseInt(ctStr, 10, 64)
if err != nil {
t.Fatalf("parse commit time: %v", err)
}
if cc.CommitTime != uint64(ct) {
t.Fatalf("commit time mismatch for %s: got %d want %d", oidStr, cc.CommitTime, ct)
}
changed := gitCmd(t, repoPath, nil, "diff-tree", "--no-commit-id", "--name-only", "-r", "--root", oidStr)
for _, path := range strings.Fields(changed) {
if path == "" {
continue
}
if !cc.ChangedPathMightContain([]byte(path)) {
t.Fatalf("bloom filter missing changed path %q in %s", path, oidStr)
}
}
if cc.ChangedPathMightContain([]byte("this-path-should-not-exist-abcdefg")) {
falsePositives++
}
}
if falsePositives > 1 {
t.Fatalf("unexpected bloom false positive rate: %d", falsePositives)
}
}
func TestCommitGraphReadExtraEdges(t *testing.T) {
workDir, cleanupWork := setupWorkDir(t)
defer cleanupWork()
gitCmd(t, workDir, nil, "init")
if err := os.WriteFile(filepath.Join(workDir, "base.txt"), []byte("base\n"), 0o644); err != nil {
t.Fatalf("write base: %v", err)
}
gitCmd(t, workDir, nil, "add", ".")
gitCmd(t, workDir, nil, "commit", "-m", "base")
gitCmd(t, workDir, nil, "checkout", "-b", "branch1")
if err := os.WriteFile(filepath.Join(workDir, "b1.txt"), []byte("b1\n"), 0o644); err != nil {
t.Fatalf("write b1: %v", err)
}
gitCmd(t, workDir, nil, "add", ".")
gitCmd(t, workDir, nil, "commit", "-m", "b1")
gitCmd(t, workDir, nil, "checkout", "master")
gitCmd(t, workDir, nil, "checkout", "-b", "branch2")
if err := os.WriteFile(filepath.Join(workDir, "b2.txt"), []byte("b2\n"), 0o644); err != nil {
t.Fatalf("write b2: %v", err)
}
gitCmd(t, workDir, nil, "add", ".")
gitCmd(t, workDir, nil, "commit", "-m", "b2")
gitCmd(t, workDir, nil, "checkout", "master")
gitCmd(t, workDir, nil, "checkout", "-b", "branch3")
if err := os.WriteFile(filepath.Join(workDir, "b3.txt"), []byte("b3\n"), 0o644); err != nil {
t.Fatalf("write b3: %v", err)
}
gitCmd(t, workDir, nil, "add", ".")
gitCmd(t, workDir, nil, "commit", "-m", "b3")
gitCmd(t, workDir, nil, "checkout", "master")
gitCmd(t, workDir, nil, "merge", "--no-ff", "-m", "octopus", "branch1", "branch2", "branch3")
gitCmd(t, workDir, nil, "repack", "-a", "-d")
gitCmd(t, workDir, nil, "commit-graph", "write", "--reachable")
repo, err := OpenRepository(filepath.Join(workDir, ".git"))
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
cg, err := repo.CommitGraph()
if err != nil {
t.Fatalf("CommitGraph failed: %v", err)
}
mergeHash := gitCmd(t, workDir, nil, "rev-parse", "HEAD")
id, _ := repo.ParseHash(mergeHash)
pos, ok := cg.CommitPosition(id)
if !ok {
t.Fatalf("merge commit not found")
}
cc, err := cg.CommitAt(pos)
if err != nil {
t.Fatalf("CommitAt failed: %v", err)
}
parentStr := gitCmd(t, workDir, nil, "show", "-s", "--format=%P", mergeHash)
parents := strings.Fields(parentStr)
if len(cc.Parents) != len(parents) {
t.Fatalf("octopus parent mismatch: got %d want %d", len(cc.Parents), len(parents))
}
}
func TestCommitGraphReadSplitChain(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
workDir, cleanupWork := setupWorkDir(t)
defer cleanupWork()
for i := 0; i < 5; i++ {
path := filepath.Join(workDir, fmt.Sprintf("file%d.txt", i))
if err := os.WriteFile(path, []byte(fmt.Sprintf("v%d\n", i)), 0o644); err != nil {
t.Fatalf("write %s: %v", path, err)
}
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "add", ".")
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "commit", "-m", fmt.Sprintf("commit %d", i))
}
gitCmd(t, repoPath, nil, "repack", "-a", "-d")
gitCmd(t, repoPath, nil, "commit-graph", "write", "--reachable", "--changed-paths", "--split=no-merge")
// more commits needed to get a split chain with base layer
for i := 5; i < 8; i++ {
path := filepath.Join(workDir, fmt.Sprintf("file%d.txt", i))
if err := os.WriteFile(path, []byte(fmt.Sprintf("v%d\n", i)), 0o644); err != nil {
t.Fatalf("write %s: %v", path, err)
}
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "add", ".")
gitCmd(t, repoPath, nil, "--work-tree="+workDir, "commit", "-m", fmt.Sprintf("commit %d", i))
}
gitCmd(t, repoPath, nil, "repack", "-a", "-d")
gitCmd(t, repoPath, nil, "commit-graph", "write", "--reachable", "--changed-paths", "--split=no-merge", "--append")
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
cg, err := repo.CommitGraph()
if err != nil {
t.Fatalf("CommitGraph failed: %v", err)
}
chainPath := filepath.Join(repoPath, "objects", "info", "commit-graphs", "commit-graph-chain")
if _, err := os.Stat(chainPath); err != nil {
t.Fatalf("commit-graph chain not created by git: %v", err)
}
if cg.base == nil {
t.Fatalf("expected split commit-graph chain")
}
if cg.numCommitsInBase == 0 {
t.Fatalf("expected non-zero base commit count")
}
revList := gitCmd(t, repoPath, nil, "rev-list", "--max-parents=0", "HEAD")
id, _ := repo.ParseHash(revList)
if _, ok := cg.CommitPosition(id); !ok {
t.Fatalf("base commit not found in commit-graph chain")
}
}
func TestCommitGraphTrailerChecksum(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
data := buildCommitGraphBytes(t, repo, 1, nil, nil, nil)
data[len(data)-1] ^= 0xff
if _, err := parseCommitGraph(repo, "corrupt.graph", data); err == nil {
t.Fatalf("expected checksum error")
}
}
func TestCommitGraphFanoutMonotonicity(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
oids := [][]byte{
bytes.Repeat([]byte{0x10}, repo.hashAlgo.Size()),
bytes.Repeat([]byte{0x20}, repo.hashAlgo.Size()),
}
data := buildCommitGraphBytes(t, repo, 2, oids, nil, nil)
start, end, ok := chunkRange(t, repo, data, commitGraphChunkOIDF)
if !ok {
t.Fatalf("OIDF chunk not found")
}
fanout := make([]byte, end-start)
copy(fanout, data[start:end])
binary.BigEndian.PutUint32(fanout[0:4], 2)
binary.BigEndian.PutUint32(fanout[4:8], 1)
data = replaceChunk(t, repo, data, commitGraphChunkOIDF, fanout)
if _, err := parseCommitGraph(repo, "bad-fanout.graph", data); err == nil {
t.Fatalf("expected fanout monotonicity error")
}
}
func TestCommitGraphBIDXMonotonicity(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
oids := [][]byte{
bytes.Repeat([]byte{0x10}, repo.hashAlgo.Size()),
bytes.Repeat([]byte{0x20}, repo.hashAlgo.Size()),
}
bidx := []uint32{8, 4}
data := buildCommitGraphBytes(t, repo, 2, oids, bidx, []byte{0, 0, 0, 0, 0, 0, 0, 0})
if _, err := parseCommitGraph(repo, "bad-bidx.graph", data); err == nil {
t.Fatalf("expected bidx monotonicity error")
}
}
func TestCommitGraphExtraEdgesBounds(t *testing.T) {
repoPath, cleanup := setupTestRepo(t)
defer cleanup()
repo, err := OpenRepository(repoPath)
if err != nil {
t.Fatalf("OpenRepository failed: %v", err)
}
defer func() { _ = repo.Close() }()
oids := [][]byte{
bytes.Repeat([]byte{0x10}, repo.hashAlgo.Size()),
bytes.Repeat([]byte{0x20}, repo.hashAlgo.Size()),
bytes.Repeat([]byte{0x30}, repo.hashAlgo.Size()),
}
extraEdges := []uint32{0x80000000 | 100}
data := buildCommitGraphBytes(t, repo, 3, oids, nil, nil)
// inject EDGE chunk with an out-of-range index
data = injectChunk(t, repo, data, commitGraphChunkEDGE, u32SliceToBytes(extraEdges))
// force the first commit to use the extra edges list
start, end, ok := chunkRange(t, repo, data, commitGraphChunkCDAT)
if !ok {
t.Fatalf("CDAT chunk not found")
}
cdat := make([]byte, end-start)
copy(cdat, data[start:end])
hashSize := repo.hashAlgo.Size()
binary.BigEndian.PutUint32(cdat[hashSize+4:hashSize+8], 0x80000000|100)
data = replaceChunk(t, repo, data, commitGraphChunkCDAT, cdat)
cg, err := parseCommitGraph(repo, "edge.graph", data)
if err != nil {
t.Fatalf("parseCommitGraph failed: %v", err)
}
pos, ok := cg.CommitPosition(hashFromBytes(repo, oids[0]))
if !ok {
t.Fatalf("commit not found")
}
if _, err := cg.CommitAt(pos); err == nil {
t.Fatalf("expected extra-edges bounds error")
}
}
func buildCommitGraphBytes(t *testing.T, repo *Repository, n int, oids [][]byte, bidx []uint32, bdat []byte) []byte {
t.Helper()
if n <= 0 {
t.Fatalf("invalid num commits")
}
hashSize := repo.hashAlgo.Size()
if len(oids) == 0 {
for i := 0; i < n; i++ {
b := bytes.Repeat([]byte{byte(0x10 + i)}, hashSize)
oids = append(oids, b)
}
}
sort.Slice(oids, func(i, j int) bool {
return bytes.Compare(oids[i], oids[j]) < 0
})
var chunks []chunkSpec
oidf := make([]byte, commitGraphFanoutSize)
for _, oid := range oids {
idx := int(oid[0])
for i := idx; i < 256; i++ {
v := binary.BigEndian.Uint32(oidf[i*4 : i*4+4])
binary.BigEndian.PutUint32(oidf[i*4:i*4+4], v+1)
}
}
chunks = append(chunks, chunkSpec{commitGraphChunkOIDF, oidf})
oidl := make([]byte, 0, n*hashSize)
for _, oid := range oids {
oidl = append(oidl, oid...)
}
chunks = append(chunks, chunkSpec{commitGraphChunkOIDL, oidl})
cdat := make([]byte, n*commitGraphCommitDataSize(repo.hashAlgo))
for i := 0; i < n; i++ {
base := i * commitGraphCommitDataSize(repo.hashAlgo)
copy(cdat[base:base+hashSize], bytes.Repeat([]byte{0xaa}, hashSize))
binary.BigEndian.PutUint32(cdat[base+hashSize:], commitGraphParentNone)
binary.BigEndian.PutUint32(cdat[base+hashSize+4:], commitGraphParentNone)
binary.BigEndian.PutUint32(cdat[base+hashSize+8:], 4)
binary.BigEndian.PutUint32(cdat[base+hashSize+12:], 0)
}
chunks = append(chunks, chunkSpec{commitGraphChunkCDAT, cdat})
if bidx != nil && bdat != nil {
bidxBytes := u32SliceToBytes(bidx)
bdatHeader := make([]byte, bloom.DataHeaderSize)
binary.BigEndian.PutUint32(bdatHeader[0:4], 2)
binary.BigEndian.PutUint32(bdatHeader[4:8], 7)
binary.BigEndian.PutUint32(bdatHeader[8:12], 10)
bdatFull := append(bdatHeader, bdat...)
chunks = append(chunks, chunkSpec{commitGraphChunkBIDX, bidxBytes})
chunks = append(chunks, chunkSpec{commitGraphChunkBDAT, bdatFull})
}
return assembleCommitGraphBytes(t, repo, chunks)
}
type chunkSpec struct {
id uint32
data []byte
}
func assembleCommitGraphBytes(t *testing.T, repo *Repository, chunks []chunkSpec) []byte {
t.Helper()
var buf bytes.Buffer
buf.Grow(1024)
var header [commitGraphHeaderSize]byte
binary.BigEndian.PutUint32(header[0:4], commitGraphSignature)
header[4] = commitGraphVersion
header[5] = hashAlgoVersion(repo.hashAlgo)
header[6] = byte(len(chunks))
header[7] = 0
buf.Write(header[:])
tocStart := buf.Len()
tocLen := (len(chunks) + 1) * commitGraphChunkEntrySize
buf.Grow(tocLen)
buf.Write(make([]byte, tocLen))
offset := tocStart + tocLen
for i, ch := range chunks {
pos := tocStart + i*commitGraphChunkEntrySize
binary.BigEndian.PutUint32(buf.Bytes()[pos:pos+4], ch.id)
binary.BigEndian.PutUint64(buf.Bytes()[pos+4:pos+12], uint64(offset))
offset += len(ch.data)
}
pos := tocStart + len(chunks)*commitGraphChunkEntrySize
binary.BigEndian.PutUint32(buf.Bytes()[pos:pos+4], 0)
binary.BigEndian.PutUint64(buf.Bytes()[pos+4:pos+12], uint64(offset))
for _, ch := range chunks {
buf.Write(ch.data)
}
h, err := repo.hashAlgo.New()
if err != nil {
t.Fatalf("hash.New failed: %v", err)
}
_, _ = h.Write(buf.Bytes())
buf.Write(h.Sum(nil))
return buf.Bytes()
}
func chunkRange(t *testing.T, repo *Repository, data []byte, id uint32) (int, int, bool) {
t.Helper()
hashSize := repo.hashAlgo.Size()
numChunks := int(data[6])
tocStart := commitGraphHeaderSize
trailerStart := len(data) - hashSize
for i := 0; i < numChunks; i++ {
pos := tocStart + i*commitGraphChunkEntrySize
chID := binary.BigEndian.Uint32(data[pos : pos+4])
if chID == 0 {
break
}
start := int(binary.BigEndian.Uint64(data[pos+4 : pos+12]))
end := trailerStart
if i+1 < numChunks {
end = int(binary.BigEndian.Uint64(data[pos+commitGraphChunkEntrySize+4 : pos+commitGraphChunkEntrySize+12]))
}
if chID == id {
return start, end, true
}
}
return 0, 0, false
}
func replaceChunk(t *testing.T, repo *Repository, data []byte, id uint32, payload []byte) []byte {
t.Helper()
hashSize := repo.hashAlgo.Size()
numChunks := int(data[6])
tocStart := commitGraphHeaderSize
trailerStart := len(data) - hashSize
chunks := make([]chunkSpec, 0, numChunks)
for i := 0; i < numChunks; i++ {
pos := tocStart + i*commitGraphChunkEntrySize
chID := binary.BigEndian.Uint32(data[pos : pos+4])
if chID == 0 {
break
}
start := int(binary.BigEndian.Uint64(data[pos+4 : pos+12]))
end := trailerStart
if i+1 < numChunks {
end = int(binary.BigEndian.Uint64(data[pos+commitGraphChunkEntrySize+4 : pos+commitGraphChunkEntrySize+12]))
}
if chID == id {
chunks = append(chunks, chunkSpec{chID, payload})
} else {
chunks = append(chunks, chunkSpec{chID, data[start:end]})
}
}
if len(chunks) == 0 {
t.Fatalf("no chunks found")
}
return assembleCommitGraphBytes(t, repo, chunks)
}
func injectChunk(t *testing.T, repo *Repository, data []byte, id uint32, payload []byte) []byte {
t.Helper()
hashSize := repo.hashAlgo.Size()
numChunks := int(data[6])
tocStart := commitGraphHeaderSize
trailerStart := len(data) - hashSize
chunks := make([]chunkSpec, 0, numChunks+1)
for i := 0; i < numChunks; i++ {
pos := tocStart + i*commitGraphChunkEntrySize
chID := binary.BigEndian.Uint32(data[pos : pos+4])
if chID == 0 {
break
}
start := int(binary.BigEndian.Uint64(data[pos+4 : pos+12]))
end := trailerStart
if i+1 < numChunks {
end = int(binary.BigEndian.Uint64(data[pos+commitGraphChunkEntrySize+4 : pos+commitGraphChunkEntrySize+12]))
}
chunks = append(chunks, chunkSpec{chID, data[start:end]})
}
chunks = append(chunks, chunkSpec{id, payload})
return assembleCommitGraphBytes(t, repo, chunks)
}
func u32SliceToBytes(vals []uint32) []byte {
out := make([]byte, len(vals)*4)
for i, v := range vals {
binary.BigEndian.PutUint32(out[i*4:i*4+4], v)
}
return out
}
func hashFromBytes(repo *Repository, b []byte) Hash {
var h Hash
copy(h.data[:], b)
h.algo = repo.hashAlgo
return h
}