Fixed a bug which prevented an empty mapping from being used as a simple key...

Fixed a bug which prevented an empty mapping from being used as a simple key (#150, thank to spitzak(at)rhythm(dot)com).

src/emitter.c

@@ -1154,7 +1154,7 @@
             break;
 
         case YAML_MAPPING_START_EVENT:
-            if (!yaml_emitter_check_empty_sequence(emitter))
+            if (!yaml_emitter_check_empty_mapping(emitter))
                 return 0;
             length += emitter->anchor_data.anchor_length
                 + emitter->tag_data.handle_length