Files
Stefan Haller cb12cb2f6b Add Status.RefsSnapshot
A cheap fingerprint of local branches and HEAD that future code can poll to
detect when refs have moved externally.

Branches come from a porcelain for-each-ref. HEAD is read directly from
.git/HEAD: that avoids spawning a child process and captures the symref-or-hash
distinction we need to tell "detached at X" apart from "on a branch pointing at
X" — they share a commit hash, which is exactly the situation at the end of a
rebase when HEAD reattaches to the branch. The reftable backend doesn't keep a
real .git/HEAD (it writes a fixed stub), so when we see that stub or the file is
unreadable we fall back to porcelain commands, which are backend-agnostic.

Uses DontLog so a future polling caller won't spam the command log. Not yet
wired up to any caller.
2026-06-19 18:07:48 +02:00

157 lines
5.6 KiB
Go

package git_commands
import (
"os"
"path/filepath"
"strings"
"time"
"github.com/jesseduffield/lazygit/pkg/commands/models"
"github.com/spf13/afero"
)
type StatusCommands struct {
*GitCommon
}
func NewStatusCommands(
gitCommon *GitCommon,
) *StatusCommands {
return &StatusCommands{
GitCommon: gitCommon,
}
}
func (self *StatusCommands) WorkingTreeState() models.WorkingTreeState {
result := models.WorkingTreeState{}
result.Rebasing, _ = self.IsInRebase()
result.Merging, _ = self.IsInMergeState()
result.CherryPicking, _ = self.IsInCherryPick()
result.Reverting, _ = self.IsInRevert()
return result
}
func (self *StatusCommands) IsBareRepo() bool {
return self.repoPaths.isBareRepo
}
func (self *StatusCommands) IsInRebase() (bool, error) {
exists, err := self.os.FileExists(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "rebase-merge"))
if err == nil && exists {
return true, nil
}
return self.os.FileExists(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "rebase-apply"))
}
// IsInMergeState states whether we are still mid-merge
func (self *StatusCommands) IsInMergeState() (bool, error) {
return self.os.FileExists(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "MERGE_HEAD"))
}
func (self *StatusCommands) IsInCherryPick() (bool, error) {
exists, err := self.os.FileExists(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "CHERRY_PICK_HEAD"))
if err != nil || !exists {
return exists, err
}
// Sometimes, CHERRY_PICK_HEAD is present during rebases even if no
// cherry-pick is in progress. I suppose this is because rebase used to be
// implemented as a series of cherry-picks, so this could be remnants of
// code that is shared between cherry-pick and rebase, or something. The way
// to tell if this is the case is to check for the presence of the
// stopped-sha file, which records the sha of the last pick that was
// executed before the rebase stopped, and seeing if the sha in that file is
// the same as the one in CHERRY_PICK_HEAD.
cherryPickHead, err := os.ReadFile(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "CHERRY_PICK_HEAD"))
if err != nil {
return false, err
}
stoppedSha, err := os.ReadFile(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "rebase-merge", "stopped-sha"))
if err != nil {
// If we get an error we assume the file doesn't exist
return true, nil
}
cherryPickHeadStr := strings.TrimSpace(string(cherryPickHead))
stoppedShaStr := strings.TrimSpace(string(stoppedSha))
// Need to use HasPrefix here because the cherry-pick HEAD is a full sha1,
// but stopped-sha is an abbreviated sha1
if strings.HasPrefix(cherryPickHeadStr, stoppedShaStr) {
return false, nil
}
return true, nil
}
func (self *StatusCommands) IsInRevert() (bool, error) {
return self.os.FileExists(filepath.Join(self.repoPaths.WorktreeGitDirPath(), "REVERT_HEAD"))
}
// RefsSnapshot returns a string fingerprint of the current state of local
// branches and HEAD. Comparing two snapshots byte-for-byte tells us whether
// any local ref or HEAD has moved since the last snapshot.
func (self *StatusCommands) RefsSnapshot() (string, error) {
t := time.Now()
defer func() { self.Log.Infof("RefsSnapshot took %s", time.Since(t)) }()
refsArgs := NewGitCmd("for-each-ref").
Arg("--format=%(objectname) %(refname)").
Arg("refs/heads").
ToArgv()
refs, err := self.cmd.New(refsArgs).DontLog().RunWithOutput()
if err != nil {
return "", err
}
head, err := self.headSnapshot()
if err != nil {
return "", err
}
return refs + head, nil
}
// headSnapshot returns a fingerprint of HEAD that distinguishes "detached at
// commit X" from "on a branch that points at X". The commit hash alone can't
// tell those apart, which matters at the end of a rebase: HEAD reattaches to
// the branch without the hash changing, and we'd otherwise miss that refresh.
//
// We read .git/HEAD directly rather than shelling out: it's faster (no child
// process) and its content is exactly the symref-or-hash distinction we want
// ("ref: refs/heads/foo" when attached, the raw hash when detached). The
// reftable backend, however, doesn't keep a real .git/HEAD — it writes a fixed
// stub ("ref: refs/heads/.invalid") that never reflects the actual HEAD. When
// we see that stub (or the file is missing/unreadable) we fall back to
// porcelain commands, which are backend-agnostic.
func (self *StatusCommands) headSnapshot() (string, error) {
headPath := filepath.Join(self.repoPaths.WorktreeGitDirPath(), "HEAD")
if content, err := afero.ReadFile(self.Fs, headPath); err == nil {
head := strings.TrimSpace(string(content))
if head != "" && head != "ref: refs/heads/.invalid" {
return head, nil
}
}
// symbolic-ref gives the branch when HEAD is attached and fails when it's
// detached, in which case rev-parse gives the commit HEAD points at.
symbolicRefArgs := NewGitCmd("symbolic-ref").Arg("HEAD").ToArgv()
if symref, err := self.cmd.New(symbolicRefArgs).DontLog().RunWithOutput(); err == nil {
return strings.TrimSpace(symref), nil
}
revParseArgs := NewGitCmd("rev-parse").Arg("HEAD").ToArgv()
head, err := self.cmd.New(revParseArgs).DontLog().RunWithOutput()
if err != nil {
return "", err
}
return strings.TrimSpace(head), nil
}
// Full ref (e.g. "refs/heads/mybranch") of the branch that is currently
// being rebased, or empty string when we're not in a rebase
func (self *StatusCommands) BranchBeingRebased() string {
for _, dir := range []string{"rebase-merge", "rebase-apply"} {
if bytesContent, err := os.ReadFile(filepath.Join(self.repoPaths.WorktreeGitDirPath(), dir, "head-name")); err == nil {
return strings.TrimSpace(string(bytesContent))
}
}
return ""
}