.

wcfs/wcfs.go

@@ -110,6 +110,9 @@
 // The client can start to use mmapped data after it gets "ok".
 // The server sends "error" reply if requested <at> is too far away back from
 // head/at.
+// XXX other errors are possible (e.g. "no such file", or error handling pin).
+// XXX error handling pin -> then client is killed?
+// XXX if not - specify that watch state is lost after error.
 //
 // Upon watch request, either initially, or after sending "ok", the server will be notifying the
 // client about file blocks that client needs to pin in order to observe file's
@@ -1399,15 +1402,14 @@ func (wlink *WatchLink) setupWatch(ctx context.Context, foid zodb.Oid, at zodb.T
 			at:     at,
 			pinned: make(map[int64]zodb.Tid),
 		}
-
 	}
 
-	// at=InvalidTid means "remove the watch"
+	// at="-" (InvalidTid) means "remove the watch"
 	// XXX locking
 	if at == zodb.InvalidTid {
 		delete(wlink.byfile, foid)
 		delete(w.file.watches, w)
-		return
+		return nil
 	}
 
 

wcfs/wcfs_test.py

@@ -1338,6 +1338,7 @@ def test_wcfs():
     w_assertPin(               {2:at3, 3:at2, 5:at0})
 
     # XXX advance watch - receives new pins/unpins to @head
+    # XXX this is already tested ^^^ in at_i -> at_j -> ...
 
     wl3.close()