fix: report IsGitRepo in worktrees and submodules (iss-72)

.abcd/work/issues/open/iss-72-core-isgitrepo-misses-worktrees.md → .abcd/work/issues/resolved/iss-72-core-isgitrepo-misses-worktrees.md

@@ -7,6 +7,7 @@ category: "bug"
 source: "agent-finding"
 found_during: "clean-slate-sweep"
 found_at: "internal/core/core.go"
+resolution: "core.Status now tests .git existence (file or dir) not dir-ness, so a linked worktree/submodule (where .git is a gitfile) reports IsGitRepo=true. os.Stat is correct (rejects dangling symlinks). ruthless SHIP; scoped to IsGitRepo only. PR opened."
 ---
 
 core.Status.IsGitRepo=false in a linked git worktree or submodule: isDir(.git) requires a directory but .git is a regular gitfile (gitlink) in worktrees/submodules, so a genuine checkout reports not-a-git-repo (core.go:47, C1). Detector: an exists-not-isDir check for .git with a worktree fixture. Corpus: C1.

CHANGELOG.md

@@ -133,6 +133,11 @@ called out in a **Breaking** section.
 - The `created` and `updated` frontmatter fields on issues. Git is the canonical
   source of an issue's timeline; the ledger no longer duplicates it.
 
+### Fixed
+
+- `abcd` status now reports `IsGitRepo` correctly in a linked git worktree or a
+  submodule, where `.git` is a regular gitfile rather than a directory (iss-72).
+
 ### Security
 
 - **Release receipt-gate hardening** (iss-70). The `receipt_gate` record-lint

internal/core/core.go

@@ -43,8 +43,11 @@ func Status(dir string) (StatusInfo, error) {
 		return StatusInfo{}, err
 	}
 	s := StatusInfo{
-		Dir:       abs,
-		IsGitRepo: isDir(filepath.Join(abs, ".git")),
+		Dir: abs,
+		// .git is a directory in a normal clone but a regular gitfile in a linked
+		// worktree or submodule — both are genuine checkouts, so test existence, not
+		// dir-ness. HasRecord/WorkTiers stay dir-only (those must be directories).
+		IsGitRepo: exists(filepath.Join(abs, ".git")),
 		HasRecord: isDir(filepath.Join(abs, ".abcd", "development")),
 	}
 	for _, tier := range []struct{ path, name string }{
@@ -63,3 +66,11 @@ func isDir(p string) bool {
 	fi, err := os.Stat(p)
 	return err == nil && fi.IsDir()
 }
+
+// exists reports whether p exists (a file or a directory). A .git gitfile in a
+// worktree/submodule is a regular file, so a plain existence check is the correct
+// "is this a git checkout" test.
+func exists(p string) bool {
+	_, err := os.Stat(p)
+	return err == nil
+}

internal/core/core_test.go

@@ -30,6 +30,23 @@ func TestStatusBareDir(t *testing.T) {
 	}
 }
 
+// TestStatusGitfileWorktree (iss-72) proves a linked worktree or submodule —
+// where .git is a regular gitfile, not a directory — is still reported as a git
+// repo. isDir would report false for a genuine checkout.
+func TestStatusGitfileWorktree(t *testing.T) {
+	dir := t.TempDir()
+	if err := os.WriteFile(filepath.Join(dir, ".git"), []byte("gitdir: /somewhere/.git/worktrees/wt\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	s, err := Status(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !s.IsGitRepo {
+		t.Fatal("a worktree/submodule .git gitfile must report IsGitRepo=true")
+	}
+}
+
 func TestStatusWithRecordAndGit(t *testing.T) {
 	dir := t.TempDir()
 	mustMkdir(t, filepath.Join(dir, ".git"))