[glib: 2/3] glocalvfs: Create a dummy file for g_file_new_for_path("")

[Sebastian Dröge <sdroege src gnome org>]

commit d52728f994058182f748d0a4e46b0141d93f4390
Author: Philip Withnall <pwithnall endlessos org>
Date:   Wed Mar 10 19:10:38 2021 +0000

    glocalvfs: Create a dummy file for g_file_new_for_path("")
    
    `""` is not a valid path (`stat()` on it returns `ENOENT`). Previously,
    a full `GLocalFile` was being created, which ended up resolving to
    `$CWD`, through path canonicalisation. That isn’t right.
    
    Fix it by creating a `GDummyFile` instead, and adding a unit test.
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>
    
    Fixes: #2328

 gio/glocalvfs.c  |  5 ++++-
 gio/tests/file.c | 21 +++++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)
---
diff --git a/gio/glocalvfs.c b/gio/glocalvfs.c
index f8d85e458..2dc0f2de7 100644
--- a/gio/glocalvfs.c
+++ b/gio/glocalvfs.c
@@ -80,7 +80,10 @@ static GFile *
 g_local_vfs_get_file_for_path (GVfs       *vfs,
                                const char *path)
 {
-  return _g_local_file_new (path);
+  if (*path == '\0')
+    return _g_dummy_file_new (path);
+  else
+    return _g_local_file_new (path);
 }
 
 static GFile *
diff --git a/gio/tests/file.c b/gio/tests/file.c
index c1a2a9360..7f5ee8e78 100644
--- a/gio/tests/file.c
+++ b/gio/tests/file.c
@@ -96,6 +96,26 @@ test_child (void)
   g_object_unref (file);
 }
 
+static void
+test_empty_path (void)
+{
+  GFile *file = NULL;
+
+  g_test_bug ("https://gitlab.gnome.org/GNOME/glib/-/issues/2328";);
+  g_test_summary ("Check that creating a file with an empty path results in errors");
+
+  /* Creating the file must always succeed. */
+  file = g_file_new_for_path ("");
+  g_assert_nonnull (file);
+
+  /* But then querying its path should indicate it’s invalid. */
+  g_assert_null (g_file_get_path (file));
+  g_assert_null (g_file_get_basename (file));
+  g_assert_null (g_file_get_parent (file));
+
+  g_object_unref (file);
+}
+
 static void
 test_type (void)
 {
@@ -2875,6 +2895,7 @@ main (int argc, char *argv[])
   g_test_add_func ("/file/build-filename", test_build_filename);
   g_test_add_func ("/file/parent", test_parent);
   g_test_add_func ("/file/child", test_child);
+  g_test_add_func ("/file/empty-path", test_empty_path);
   g_test_add_func ("/file/type", test_type);
   g_test_add_func ("/file/parse-name", test_parse_name);
   g_test_add_data_func ("/file/async-create-delete/0", GINT_TO_POINTER (0), test_create_delete);