lib/refs: Ignore files starting with . in refs/

Ignore any files that start with a `.` under the assumption they're metadata for
some other tool. This is a bit ugly as `.` *is* valid in refs, but I don't see
many people using that in the wild.

Closes: ostreedev#1285

src/libostree/ostree-repo-refs.c

@@ -560,6 +560,14 @@ enumerate_refs_recurse (OstreeRepo    *repo,
       if (dent == NULL)
         break;
 
+      /* https://github.com/ostreedev/ostree/issues/1285
+       * Ignore any files that start with a `.` under the assumption they're
+       * metadata for some other tool.  This is a bit ugly as `.` *is* valid
+       * in refs, but I don't see many people using that in the wild.
+       **/
+      if (g_str_has_prefix (dent->d_name, "."))
+        continue;
+
       g_string_append (base_path, dent->d_name);
 
       if (dent->d_type == DT_DIR)

tests/test-refs.sh

@@ -88,6 +88,19 @@ if ${CMD_PREFIX} ostree --repo=repo refs foo/ctest --create=ctest; then
     assert_not_reached "refs --create unexpectedly succeeded in overwriting an existing prefix!"
 fi
 
+# https://github.com/ostreedev/ostree/issues/1285
+# One tool was creating .latest_rsync files in each dir, let's ignore stuff like
+# that.
+echo '👻' > repo/refs/heads/.spooky_and_hidden
+ostree --repo=repo refs > refs.txt
+assert_not_file_has_content refs.txt 'spooky'
+${CMD_PREFIX} ostree --repo=repo refs ctest --create=exampleos/x86_64/standard
+echo '👻' > repo/refs/heads/exampleos/x86_64/.further_spooky_and_hidden
+ostree --repo=repo refs > refs.txt
+assert_file_has_content refs.txt 'exampleos/x86_64/standard'
+assert_not_file_has_content refs.txt 'spooky'
+rm repo/refs/heads/exampleos -rf
+
 #Check to see if any uncleaned tmp files were created after failed --create
 ${CMD_PREFIX} ostree --repo=repo refs | wc -l > refscount.create1
 assert_file_has_content refscount.create1 "^5$"