.

wcfs/wcfs_test.py

@@ -878,6 +878,7 @@ def watch(twlink, zf, at, pinok=None): # -> tWatch
     print('\nC: setup watch f<%s> %s%s' % (h(zf._p_oid), at_from, t.hat(at)))
 
     headOfAccess = t._headOfAccess(zf)
+    blkRevAt     = lambda blk, at: t._blkRevAt(zf, blk, at)
 
     pin_prev = {}
     if at_prev is not None:
@@ -894,25 +895,33 @@ def watch(twlink, zf, at, pinok=None): # -> tWatch
         # blk ∉ pin_prev,   blk ∉ pin       -> cannot happen
         assert (blk in pin_prev) or (blk in pin)
 
-        # blk ∉ pin_prev,   blk ∈ pin       -> cannot happen
+        # blk ∉ pin_prev,   blk ∈ pin       -> cannot happen, except on first start
         if blk not in pin_prev and blk in pin:
             if at_prev is not None:
                 assert False, '#%d pinned %s; not pinned %s' % (t.hat(at_prev), t.hat(at))
 
+            # blk ∈ pin     -> blk was already accessed with rev > at
+            assert blk in headOfAccess
+            assert at  <  blkRevAt(blk, headOfAccess[blk])
+
         # blk ∈ pin_prev,   blk ∉ pin       -> unpin to head
         elif blk in pin_prev and blk not in pin:
-            # blk ∈ pin_prev means blk was already accessed with rev > at_prev
+            # blk ∈ pin_prev -> blk was already accessed with rev > at_prev
             assert blk in headOfAccess
-            assert t._blkRevAt(blk, headOfAccess[blk]) > at_prev
+            assert at_prev < blkRevAt(blk, headOfAccess[blk])
 
-            # blk ∉ pin      means XXX
-            assert headOfAccess[blk] >= t._blkRevAt(blk, t.head)
+            # blk ∉ pin      -> blk revision as of last access is ≤ at
+            assert blkRevAt(blk, headOfAccess[blk]) <= at
 
             pin[blk] = None     # @head
 
         # blk ∈ pin_prev,   blk ∈ pin       -> if rev different: use pin
         elif blk in pin_prev and blk in pin:
-            # XXX headOfAccess assert
+            # blk ∈ pin_prev, pin   -> blk was already accessed with rev > at_prev, at
+            assert blk in headOfAccess
+            assert at_prev < blkRevAt(blk, headOfAccess[blk])
+            assert at      < blkRevAt(blk, headOfAccess[blk])
+
             assert pin_prev[blk] <= pin[blk]
             if pin_prev[blk] == pin[blk]:
                 del pin[blk]    # would need to pin to what it is already pinned