Minor refactorisation of cache_retrieved

patacrep/songs/__init__.py

@@ -98,10 +98,10 @@ class Song:
     def __init__(self, subpath, config, *, datadir=None):
         if datadir is None:
             self.datadir = ""
+            # Only songs in datadirs may be cached
             self.use_cache = False
         else:
             self.datadir = datadir
-            # Only songs in datadirs are cached
             self.use_cache = ('_cache' in config)
 
         self.fullpath = os.path.join(self.datadir, subpath)
@@ -145,11 +145,10 @@ class Song:
 
     def _cache_retrieved(self):
         """If relevant, retrieve self from the cache."""
-        if self.use_cache:
+        if self.use_cache and os.path.exists(self.cached_name):
             self._filehash = hashlib.md5(
                 open(self.fullpath, 'rb').read()
                 ).hexdigest()
-            if os.path.exists(self.cached_name):
             try:
                 cached = pickle.load(open(
                     self.cached_name,