diff --git a/src/ClaudeDo.Data/Git/GitService.cs b/src/ClaudeDo.Data/Git/GitService.cs
index aa10b335..6fcd0f3a 100644
--- a/src/ClaudeDo.Data/Git/GitService.cs
+++ b/src/ClaudeDo.Data/Git/GitService.cs
@@ -376,6 +376,32 @@ public sealed class GitService
throw new InvalidOperationException($"git add '{path}' failed (exit {exitCode}): {stderr}");
}
+ ///
+ /// Stages as deleted (`git rm -f`), removing it from both the index
+ /// and, if present, the working tree. Used to resolve a merge conflict to "keep the
+ /// deletion" — unlike , which would stage an empty file as a
+ /// tracked, zero-byte file rather than actually removing it.
+ ///
+ public async Task RemovePathAsync(string repoDir, string path, CancellationToken ct = default)
+ {
+ var (exitCode, _, stderr) = await RunGitAsync(repoDir, ["rm", "-f", "--", path], ct);
+ if (exitCode != 0)
+ throw new InvalidOperationException($"git rm '{path}' failed (exit {exitCode}): {stderr}");
+ }
+
+ ///
+ /// Content of at a merge stage (1=base, 2=ours, 3=theirs) via
+ /// `git show :<stage>:<path>`. Null when that stage doesn't exist for the path —
+ /// the conventional way to tell a modify/delete or rename/delete conflict apart from an
+ /// ordinary content conflict (git never writes `<<<<<<<` markers for those,
+ /// it just leaves whichever side wasn't deleted in the working tree).
+ ///
+ public async Task ShowConflictStageAsync(string repoDir, int stage, string path, CancellationToken ct = default)
+ {
+ var (exitCode, stdout, _) = await RunGitAsync(repoDir, ["show", $":{stage}:{path}"], ct, trimOutput: false);
+ return exitCode == 0 ? stdout : null;
+ }
+
///
/// Non-destructive mergeability probe via `git merge-tree --write-tree`. Writes only
/// loose objects — the working tree, index, and refs are left untouched.
diff --git a/src/ClaudeDo.Worker/Lifecycle/TaskMergeService.cs b/src/ClaudeDo.Worker/Lifecycle/TaskMergeService.cs
index e37059b1..59ddc1f6 100644
--- a/src/ClaudeDo.Worker/Lifecycle/TaskMergeService.cs
+++ b/src/ClaudeDo.Worker/Lifecycle/TaskMergeService.cs
@@ -520,20 +520,48 @@ public sealed class TaskMergeService
var oldTargetTip = await _git.RevParseHeadAsync(list.WorkingDir, ct);
// Validate BEFORE staging: `git add` marks a conflicted path resolved regardless of
- // its content, so an unresolved file with markers still in it would otherwise get
- // staged (and committed) as-is. Check text content for markers first; binary files
- // can't carry markers, so they're left to the post-stage index check below.
+ // its content, so an unresolved file needs a positively-checked resolution, not just
+ // "whatever happens to be on disk". For an ordinary content conflict, git always
+ // starts the file with markers, so their absence reliably means someone resolved it
+ // (in-app or in an external editor). A modify/delete or rename/delete conflict never
+ // gets markers at all (GetConflictDocumentsAsync) — the same marker-less state also
+ // describes a file nobody has touched — so those are additionally checked against
+ // what git itself left on disk by default (whichever side wasn't deleted); still
+ // matching that default means still unresolved.
var unresolved = await _git.ListConflictedFilesAsync(list.WorkingDir, ct);
var stillConflicted = new List();
+ var toAdd = new List();
+ var toRemove = new List();
foreach (var path in unresolved)
{
var full = Path.Combine(list.WorkingDir, path.Replace('/', Path.DirectorySeparatorChar));
- string text;
- try { text = await File.ReadAllTextAsync(full, ct); }
- catch { continue; }
+ string? text = null;
+ if (File.Exists(full))
+ {
+ try { text = await File.ReadAllTextAsync(full, ct); }
+ catch { /* treated as unresolved below */ }
+ }
- if (!LooksBinary(text) && ConflictMarkerParser.HasConflicts(text))
+ if (text is not null && (LooksBinary(text) || ConflictMarkerParser.HasConflicts(text)))
+ {
stillConflicted.Add(path);
+ continue;
+ }
+
+ var oursStage = await _git.ShowConflictStageAsync(list.WorkingDir, 2, path, ct);
+ var theirsStage = await _git.ShowConflictStageAsync(list.WorkingDir, 3, path, ct);
+ var isModifyDeleteStyle = oursStage is null || theirsStage is null;
+ if (isModifyDeleteStyle &&
+ NormalizeLineEndings(text ?? "") == NormalizeLineEndings(oursStage ?? theirsStage ?? ""))
+ {
+ stillConflicted.Add(path);
+ continue;
+ }
+
+ if (text is null || text.Length == 0)
+ toRemove.Add(path);
+ else
+ toAdd.Add(path);
}
if (stillConflicted.Count > 0)
@@ -550,8 +578,10 @@ public sealed class TaskMergeService
// Stage exactly the resolved conflict paths — never `git add -A`, which would sweep
// untracked/unrelated changes left by other sessions into this merge commit (the
// target working dir is shared).
- foreach (var path in unresolved)
+ foreach (var path in toAdd)
await _git.AddPathAsync(list.WorkingDir, path, ct);
+ foreach (var path in toRemove)
+ await _git.RemovePathAsync(list.WorkingDir, path, ct);
var remaining = await _git.ListConflictedFilesAsync(list.WorkingDir, ct);
if (remaining.Count > 0)
@@ -680,6 +710,15 @@ public sealed class TaskMergeService
///
/// Reads each conflicted working-tree file and parses its conflict markers into line-level
/// segments (with the diff3 merge base when present). Binary files are flagged and skipped.
+ /// A path with no text markers on disk is either an ordinary content conflict that's already
+ /// been resolved (git keeps both index stages until the path is staged, whether or not the
+ /// working tree still looks conflicted — reads as a single stable segment, 0 hunks left), or
+ /// a modify/delete or rename/delete conflict — git never writes markers for those at all, it
+ /// just leaves whichever side wasn't deleted sitting in the working tree, so the same
+ /// "no markers" state also describes an untouched file. The index tells the two apart: a
+ /// modify/delete-style conflict only ever populates ONE of the ours/theirs stages. Those are
+ /// synthesized into a single whole-file conflict block straight from the stages (empty side
+ /// = that side deleted the path) so the resolver still shows a real choice.
///
public async Task GetConflictDocumentsAsync(string taskId, CancellationToken ct)
{
@@ -692,21 +731,53 @@ public sealed class TaskMergeService
foreach (var path in files)
{
var full = Path.Combine(list.WorkingDir, path.Replace('/', Path.DirectorySeparatorChar));
- string text;
- try { text = await File.ReadAllTextAsync(full, ct); }
- catch { text = ""; }
+ string? diskText = null;
+ if (File.Exists(full))
+ {
+ try { diskText = await File.ReadAllTextAsync(full, ct); }
+ catch { /* unreadable — fall through to the index stages below */ }
+ }
- if (LooksBinary(text))
+ if (diskText is not null && LooksBinary(diskText))
{
result.Add(new ConflictDocumentContent(path, true, Array.Empty()));
continue;
}
- result.Add(new ConflictDocumentContent(path, false, ConflictMarkerParser.Parse(text)));
+ if (diskText is not null && ConflictMarkerParser.HasConflicts(diskText))
+ {
+ result.Add(new ConflictDocumentContent(path, false, ConflictMarkerParser.Parse(diskText)));
+ continue;
+ }
+
+ var ours = await _git.ShowConflictStageAsync(list.WorkingDir, 2, path, ct);
+ var theirs = await _git.ShowConflictStageAsync(list.WorkingDir, 3, path, ct);
+ if (ours is not null && theirs is not null)
+ {
+ // Ordinary two-sided conflict, already resolved (no markers left) but not yet staged.
+ result.Add(new ConflictDocumentContent(path, false,
+ new[] { MergeSegment.Stable(diskText ?? "") }));
+ continue;
+ }
+
+ if (LooksBinary(ours ?? "") || LooksBinary(theirs ?? ""))
+ {
+ result.Add(new ConflictDocumentContent(path, true, Array.Empty()));
+ continue;
+ }
+
+ var @base = await _git.ShowConflictStageAsync(list.WorkingDir, 1, path, ct);
+ result.Add(new ConflictDocumentContent(
+ path, false, new[] { MergeSegment.Conflict(ours ?? "", @base, theirs ?? "") }));
}
return new ConflictDocuments(taskId, result);
}
+ // Working-tree checkouts can go through autocrlf while `git show :stage:path` never does —
+ // normalize before comparing the two or an untouched file reads as "resolved" on a machine
+ // with autocrlf enabled.
+ private static string NormalizeLineEndings(string text) => text.Replace("\r\n", "\n").Replace('\r', '\n');
+
// A NUL byte in the head of the file is the conventional binary sniff.
private static bool LooksBinary(string text)
{
@@ -722,6 +793,15 @@ public sealed class TaskMergeService
if (string.IsNullOrWhiteSpace(list.WorkingDir))
throw new InvalidOperationException("list has no working directory");
+ if (content.Length == 0)
+ {
+ // An empty resolution for a whole-file conflict (modify/delete, rename/delete) means
+ // "keep the deletion" — `git add` on an empty file would instead stage it as a
+ // tracked, zero-byte file, which is not what accepting the deleted side means.
+ await _git.RemovePathAsync(list.WorkingDir, path, ct);
+ return;
+ }
+
var full = Path.Combine(list.WorkingDir, path.Replace('/', Path.DirectorySeparatorChar));
await File.WriteAllTextAsync(full, content, ct);
await _git.AddPathAsync(list.WorkingDir, path, ct);
diff --git a/tests/ClaudeDo.Worker.Tests/Services/TaskMergeServiceTests.cs b/tests/ClaudeDo.Worker.Tests/Services/TaskMergeServiceTests.cs
index 7db0c193..af53837d 100644
--- a/tests/ClaudeDo.Worker.Tests/Services/TaskMergeServiceTests.cs
+++ b/tests/ClaudeDo.Worker.Tests/Services/TaskMergeServiceTests.cs
@@ -1109,6 +1109,63 @@ public class TaskMergeServiceTests : IDisposable
Assert.Contains(file.Segments, s => !s.IsConflict && s.Text.Contains("line1"));
}
+ // git never writes <<<<<<< markers for a modify/delete conflict -- it just leaves the
+ // modifying side's content sitting in the working tree, which used to read as an
+ // already-resolved stable file (no conflict at all) to both GetConflictDocumentsAsync and
+ // ContinueMergeAsync's marker scan, so `continue_merge` would silently keep the modification.
+ [Fact]
+ public async Task ModifyDeleteConflict_IsSynthesizedAndCannotBeSilentlyStaged()
+ {
+ if (!GitRepoFixture.IsGitAvailable()) return;
+
+ var db = NewDb();
+ var repo = NewRepo();
+ GitRepoFixture.RunGit(repo.RepoDir, "branch", "-m", "main");
+
+ var wtPath = Path.Combine(Path.GetTempPath(), $"wt_{Guid.NewGuid():N}");
+ _wtCleanups.Add((repo.RepoDir, wtPath));
+ GitRepoFixture.RunGit(repo.RepoDir, "worktree", "add", "-b", "claudedo/modify-delete", wtPath, repo.BaseCommit);
+ File.WriteAllText(Path.Combine(wtPath, "README.md"), "# modified by branch\n");
+ GitRepoFixture.RunGit(wtPath, "commit", "-am", "branch modifies README");
+
+ GitRepoFixture.RunGit(repo.RepoDir, "rm", "README.md");
+ GitRepoFixture.RunGit(repo.RepoDir, "commit", "-m", "main deletes README");
+
+ var (_, task) = await SeedListAndTask(db, workingDir: repo.RepoDir, status: TaskStatus.Done);
+ await SeedWorktree(db, task.Id, wtPath, "claudedo/modify-delete", repo.BaseCommit);
+
+ var (svc, _) = BuildService(db);
+ var merge = await svc.MergeAsync(task.Id, "main", removeWorktree: false, "msg",
+ leaveConflictsInTree: true, CancellationToken.None);
+ Assert.Equal(TaskMergeService.StatusConflict, merge.Status);
+
+ // No <<<<<<< markers anywhere -- git left the branch's modification as-is.
+ Assert.DoesNotContain("<<<<<<<", File.ReadAllText(Path.Combine(repo.RepoDir, "README.md")));
+
+ var docs = await svc.GetConflictDocumentsAsync(task.Id, CancellationToken.None);
+ var file = Assert.Single(docs.Files);
+ Assert.EndsWith("README.md", file.Path.Replace('\\', '/'));
+ Assert.False(file.IsBinary);
+ var conflict = Assert.Single(file.Segments.Where(s => s.IsConflict).ToList());
+ Assert.Equal("", conflict.Ours); // ours (main) deleted it
+ Assert.Contains("modified by branch", conflict.Theirs); // theirs (branch) modified it
+
+ // Nobody resolved it — continue must refuse rather than silently keeping the modification.
+ var headBefore = GitRepoFixture.RunGit(repo.RepoDir, "rev-parse", "HEAD").Trim();
+ var refused = await svc.ContinueMergeAsync(task.Id, CancellationToken.None);
+ Assert.Equal(TaskMergeService.StatusConflict, refused.Status);
+ Assert.Contains("README.md", refused.ConflictFiles);
+ Assert.Equal(headBefore, GitRepoFixture.RunGit(repo.RepoDir, "rev-parse", "HEAD").Trim());
+ Assert.True(await new GitService().IsMidMergeAsync(repo.RepoDir));
+
+ // Explicitly resolving to the deleted (ours) side must `git rm`, not stage an empty file.
+ await svc.WriteResolutionAsync(task.Id, "README.md", "", CancellationToken.None);
+ var result = await svc.ContinueMergeAsync(task.Id, CancellationToken.None);
+ Assert.Equal(TaskMergeService.StatusMerged, result.Status);
+ Assert.False(File.Exists(Path.Combine(repo.RepoDir, "README.md")));
+ Assert.False(await new GitService().IsMidMergeAsync(repo.RepoDir));
+ }
+
[Fact]
public async Task ApproveAndMergeAsync_NoWorktree_MarksDone()
{