Merge pull request #772 from edwardlonghurst/savecacheuid

Fix Infinte loop with filecache and check_files=True #738

Author: martindurant

fsspec/implementations/cached.py

@@ -161,6 +161,7 @@ def save_cache(self):
                     else:
                         c["blocks"] = set(c["blocks"]).union(cache[k]["blocks"])
                     c["time"] = max(c["time"], cache[k]["time"])
+                    c["uid"] = cache[k]["uid"]
 
             # Files can be added to cache after it was written once
             for k, c in cache.items():

fsspec/implementations/tests/test_cached.py

@@ -528,6 +528,8 @@ def test_filecache_with_checks():
 
     assert fs.cat(f1) == data  # does not change
     assert fs2.cat(f1) == data * 2  # changed, since origin changed
+    with fs2.open(f1) as f:
+        assert f.read() == data * 2  # read also sees new data
     time.sleep(0.11)  # allow cache details to expire
     assert fs.cat(f1) == data * 2  # changed, since origin changed