.

wcfs/wcfs_test.py

@@ -982,7 +982,11 @@ def test_wcfs():
 
     ev = []
     def _(ctx):
+        print()
+        print('AAA')
+        raise RuntimeError('zzz')
         pinv = wl._expectPin(ctx, zf, pinok)
+        print('BBB')
         ev.append('pin rx')
         tdelay()    # XXX doc
 
@@ -1006,8 +1010,21 @@ def test_wcfs():
         ev.append('read pre')
 
         # access data with released GIL so that the thread that reads data from
-        # head/watch can receive pin message.
-        b = read0_nogil(blk_data)
+        # head/watch can receive pin message. Be careful to handle cancelation,
+        # so that on error in another worker we don't stuck and the error is
+        # successfully propagated to wait and reported.
+        have_read = chan(1)
+        def _():
+            b = read0_nogil(blk_data)
+            have_read.send(b)
+        go(_)
+        _, _rx = select(
+            ctx.done().recv,    # 0
+            have_read.recv,     # 1
+        )
+        if _ == 0:
+            raise ctx.err()
+        b = _rx
 
         ev.append('read ' + chr(b))
         # cancel _expectPin waiting upon waking up from read from wcfs