From 4035d0b5961fcb692098f9e908faa8313c4b58b4 Mon Sep 17 00:00:00 2001
From: Min Huang <70873102+min0625@users.noreply.github.com>
Date: Thu, 2 Jul 2026 06:14:21 +0000
Subject: [PATCH 1/2] =?UTF-8?q?fix:=20update=20error=20hints=20to=20refere?=
 =?UTF-8?q?nce=20`subdir`=20after=20path=E2=86=92subdir=20rename?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The hints in fetcher and hasher still told users to check a mistyped
`path` in the manifest, but the field was renamed to `subdir` in #31.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 internal/fetcher/fetcher.go | 4 ++--
 internal/hasher/hasher.go   | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/internal/fetcher/fetcher.go b/internal/fetcher/fetcher.go
index 7b6844c..5e17b2a 100644
--- a/internal/fetcher/fetcher.go
+++ b/internal/fetcher/fetcher.go
@@ -48,7 +48,7 @@ func Fetch(ctx context.Context, cacheRoot, name, repo, commit, version, path, ds
 		if !ok {
 			return time.Time{}, clierr.New(clierr.CodeConfig,
 				fmt.Sprintf("path %q of dependency %q not found at commit %.12s", path, name, commit),
-				"an empty or missing path is almost always a mistyped `path` — check the manifest",
+				"an empty or missing path is almost always a mistyped `subdir` — check the manifest",
 			)
 		}
 	}
@@ -75,7 +75,7 @@ func Fetch(ctx context.Context, cacheRoot, name, repo, commit, version, path, ds
 		if info, err := os.Stat(treeRoot); err != nil || !info.IsDir() {
 			return time.Time{}, clierr.New(clierr.CodeConfig,
 				fmt.Sprintf("path %q of dependency %q not found at commit %.12s", path, name, commit),
-				"an empty or missing path is almost always a mistyped `path` — check the manifest",
+				"an empty or missing path is almost always a mistyped `subdir` — check the manifest",
 			)
 		}
 	}
diff --git a/internal/hasher/hasher.go b/internal/hasher/hasher.go
index e72a185..5a272c1 100644
--- a/internal/hasher/hasher.go
+++ b/internal/hasher/hasher.go
@@ -165,7 +165,7 @@ func HashTree(root string) (string, error) {
 	if len(digests) == 0 {
 		return "", clierr.New(clierr.CodeConfig,
 			"the dependency tree contains no files",
-			"an empty dependency is almost always a mistyped `path` — check the manifest",
+			"an empty dependency is almost always a mistyped `subdir` — check the manifest",
 		)
 	}
 

From c29bdcfde1f2e38cc7b24a1bf6f1f5487ee73318 Mon Sep 17 00:00:00 2001
From: Min Huang <70873102+min0625@users.noreply.github.com>
Date: Thu, 2 Jul 2026 06:20:43 +0000
Subject: [PATCH 2/2] test: cover the subdir-is-a-file branch in fetcher

Codecov flagged the post-checkout "not a directory" branch as the only
uncovered line of the patch; exercise it with a subdir that points at a
blob, which passes the ls-tree existence check.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 internal/fetcher/fetcher.go      |  8 ++++----
 internal/fetcher/fetcher_test.go | 15 +++++++++++++++
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/internal/fetcher/fetcher.go b/internal/fetcher/fetcher.go
index 5e17b2a..99e8202 100644
--- a/internal/fetcher/fetcher.go
+++ b/internal/fetcher/fetcher.go
@@ -47,8 +47,8 @@ func Fetch(ctx context.Context, cacheRoot, name, repo, commit, version, path, ds
 
 		if !ok {
 			return time.Time{}, clierr.New(clierr.CodeConfig,
-				fmt.Sprintf("path %q of dependency %q not found at commit %.12s", path, name, commit),
-				"an empty or missing path is almost always a mistyped `subdir` — check the manifest",
+				fmt.Sprintf("subdir %q of dependency %q not found at commit %.12s", path, name, commit),
+				"an empty or missing subdir is almost always a typo — check the manifest",
 			)
 		}
 	}
@@ -74,8 +74,8 @@ func Fetch(ctx context.Context, cacheRoot, name, repo, commit, version, path, ds
 
 		if info, err := os.Stat(treeRoot); err != nil || !info.IsDir() {
 			return time.Time{}, clierr.New(clierr.CodeConfig,
-				fmt.Sprintf("path %q of dependency %q not found at commit %.12s", path, name, commit),
-				"an empty or missing path is almost always a mistyped `subdir` — check the manifest",
+				fmt.Sprintf("subdir %q of dependency %q is not a directory at commit %.12s", path, name, commit),
+				"a subdir must point at a directory in the dependency repo — check the manifest",
 			)
 		}
 	}
diff --git a/internal/fetcher/fetcher_test.go b/internal/fetcher/fetcher_test.go
index 0c757c6..5293c78 100644
--- a/internal/fetcher/fetcher_test.go
+++ b/internal/fetcher/fetcher_test.go
@@ -171,6 +171,21 @@ func TestFetch_missingPath(t *testing.T) {
 	}
 }
 
+func TestFetch_pathIsFile(t *testing.T) {
+	t.Parallel()
+
+	r := gittest.New(t)
+	r.WriteFile("a.txt", "x\n")
+	sha := r.Commit("first")
+
+	// ls-tree reports the blob, so the pre-checkout existence check passes and
+	// the "not a directory" branch after checkout must catch it.
+	_, err := fetcher.Fetch(t.Context(), cacheRoot(t), depName, r.URL(), sha, "", "a.txt", fetchDst(t))
+	if got := clierr.ExitCode(err); got != int(clierr.CodeConfig) {
+		t.Fatalf("exit code = %d, want %d (error: %v)", got, clierr.CodeConfig, err)
+	}
+}
+
 func TestFetch_commitGone(t *testing.T) {
 	t.Parallel()