[glib] xdgmime: fix special case for mime_type_subclass

[Philip Withnall <pwithnall src gnome org>]

commit eb7b796bd206c31e336c89fb828a8a343ffb34ba
Author: Alexandru Pandelea <alexandru pandelea gmail com>
Date:   Wed May 10 19:09:35 2017 +0300

    xdgmime: fix special case for mime_type_subclass
    
    Currently, all mime types are considered subclasses of
    application/octet-stream, but according to the freedesktop
    standard, everything but the inode/* types is a subclass of
    application/octet-stream.
    
    Update the special case for application/octet-stream so that all
    types but inode/* will match with it and add unit test for it.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=782311

 gio/tests/contenttype.c    |   18 ++++++++++++++++++
 gio/xdgmime/xdgmime.c      |    3 ++-
 gio/xdgmime/xdgmimecache.c |    3 ++-
 3 files changed, 22 insertions(+), 2 deletions(-)
---
diff --git a/gio/tests/contenttype.c b/gio/tests/contenttype.c
index 7930002..1acbd77 100644
--- a/gio/tests/contenttype.c
+++ b/gio/tests/contenttype.c
@@ -324,11 +324,27 @@ test_tree (void)
    }
 }
 
+static void
+test_type_is_a_special_case (void)
+{
+  gboolean res;
+
+  g_test_bug ("782311");
+
+  /* Everything but the inode type is application/octet-stream */
+  res = g_content_type_is_a ("inode/directory", "application/octet-stream");
+  g_assert_false (res);
+  res = g_content_type_is_a ("anything", "application/octet-stream");
+  g_assert_true (res);
+}
+
 int
 main (int argc, char *argv[])
 {
   g_test_init (&argc, &argv, NULL);
 
+  g_test_bug_base ("http://bugzilla.gnome.org/";);
+
   g_test_add_func ("/contenttype/guess", test_guess);
   g_test_add_func ("/contenttype/unknown", test_unknown);
   g_test_add_func ("/contenttype/subtype", test_subtype);
@@ -338,6 +354,8 @@ main (int argc, char *argv[])
   g_test_add_func ("/contenttype/icon", test_icon);
   g_test_add_func ("/contenttype/symbolic-icon", test_symbolic_icon);
   g_test_add_func ("/contenttype/tree", test_tree);
+  g_test_add_func ("/contenttype/test_type_is_a_special_case",
+                   test_type_is_a_special_case);
 
   return g_test_run ();
 }
diff --git a/gio/xdgmime/xdgmime.c b/gio/xdgmime/xdgmime.c
index 42dda58..9ba224a 100644
--- a/gio/xdgmime/xdgmime.c
+++ b/gio/xdgmime/xdgmime.c
@@ -791,7 +791,8 @@ _xdg_mime_mime_type_subclass (const char *mime,
       strncmp (umime, "text/", 5) == 0)
     return 1;
 
-  if (strcmp (ubase, "application/octet-stream") == 0)
+  if (strcmp (ubase, "application/octet-stream") == 0 &&
+      strncmp (umime, "inode/", 6) != 0)
     return 1;
   
   parents = _xdg_mime_parent_list_lookup (parent_list, umime);
diff --git a/gio/xdgmime/xdgmimecache.c b/gio/xdgmime/xdgmimecache.c
index 9ea32c8..e2d49ed 100644
--- a/gio/xdgmime/xdgmimecache.c
+++ b/gio/xdgmime/xdgmimecache.c
@@ -925,7 +925,8 @@ _xdg_mime_cache_mime_type_subclass (const char *mime,
       strncmp (umime, "text/", 5) == 0)
     return 1;
 
-  if (strcmp (ubase, "application/octet-stream") == 0)
+  if (strcmp (ubase, "application/octet-stream") == 0 &&
+      strncmp (umime, "inode/", 6) != 0)
     return 1;
  
   for (i = 0; _caches[i]; i++)