From e742d83fa0d896b1311c987dfe1dd86d2bb5a318 Mon Sep 17 00:00:00 2001
From: TangoEnSkai <21152231+TangoEnSkai@users.noreply.github.com>
Date: Sat, 22 Aug 2026 12:53:28 +0900
Subject: [PATCH] libs/fileset: cover leading-slash anchoring in glob patterns

NewGlobSet compiles include patterns with go-gitignore, so a leading slash
anchors the pattern to the fileset root while a bare name matches at any
depth. Nothing tested that distinction, even though sync.include depends on
it to select a top-level directory without also matching same-named
directories nested deeper.

Add a test that pins both halves: "/dir/" selects only the root directory,
"dir/" selects the nested one as well.
---
 libs/fileset/glob_test.go | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/libs/fileset/glob_test.go b/libs/fileset/glob_test.go
index 40388996447..365b96f55d5 100644
--- a/libs/fileset/glob_test.go
+++ b/libs/fileset/glob_test.go
@@ -2,7 +2,9 @@ package fileset
 
 import (
 	"io/fs"
+	"os"
 	"path"
+	"path/filepath"
 	"slices"
 	"strings"
 	"testing"
@@ -132,3 +134,32 @@ func TestGlobFilesetDoubleQuotesWithFilePatterns(t *testing.T) {
 	require.NoError(t, err)
 	require.ElementsMatch(t, entries, collectRelativePaths(files))
 }
+
+// A pattern with a leading slash is anchored to the fileset root, the same way
+// git treats it in .gitignore. Without the slash the pattern matches a directory
+// of that name at any depth. sync.include relies on this to select, say, a
+// top-level "resources" directory without also picking up "vendor/resources".
+func TestGlobFilesetLeadingSlashAnchorsToRoot(t *testing.T) {
+	tmpDir := t.TempDir()
+	require.NoError(t, os.MkdirAll(filepath.Join(tmpDir, "dir"), 0o755))
+	require.NoError(t, os.MkdirAll(filepath.Join(tmpDir, "nested", "dir"), 0o755))
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "dir", "a.txt"), []byte("a"), 0o644))
+	require.NoError(t, os.WriteFile(filepath.Join(tmpDir, "nested", "dir", "b.txt"), []byte("b"), 0o644))
+
+	root := vfs.MustNew(tmpDir)
+
+	g, err := NewGlobSet(root, []string{"/dir/"})
+	require.NoError(t, err)
+	files, err := g.Files()
+	require.NoError(t, err)
+	require.ElementsMatch(t, []string{filepath.Join("dir", "a.txt")}, collectRelativePaths(files))
+
+	g, err = NewGlobSet(root, []string{"dir/"})
+	require.NoError(t, err)
+	files, err = g.Files()
+	require.NoError(t, err)
+	require.ElementsMatch(t, []string{
+		filepath.Join("dir", "a.txt"),
+		filepath.Join("nested", "dir", "b.txt"),
+	}, collectRelativePaths(files))
+}