--wait waits on the pane its look answered, read on the look's own open, not one found again by name in /index

The forwarded look was a write and nothing more, and --wait then
looked its file up in /index. /index shows names escaped (`\\` for a
backslash, `\xNN`), so a file named with one matched no pane and
--wait exited 0 at once, as if the pane were already closed. The look
is now asked on one open (Client.ask) and its answer is the pane
waited on; /index by name stays only for a look that answers none.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 16 insertions, 0 deletions

diff --git a/test/fs.py b/test/fs.py
index fcd779d1..483ef320 100644
--- a/test/fs.py
+++ b/test/fs.py
@@ -1395,6 +1395,22 @@ def test(binary, quic=False):
             assert time.monotonic() - deleted < .05, time.monotonic() - deleted
             assert second.wait(timeout=5) == 0
             assert edited.read_bytes() == b'edited\n'
+            # --wait waits on the pane its look answered, on the look's own
+            # open: a name /index shows escaped (a backslash is `\\` there)
+            # is still the pane waited on, not one already gone.
+            odd = root / 'wait\\odd.txt'
+            odd.write_bytes(b'odd\n')
+            before = serials()
+            waiting = subprocess.Popen([binary, '--wait', str(odd)], cwd=root, env=env,
+                                       stdout=subprocess.DEVNULL, stderr=subprocess.PIPE)
+            deadline = time.monotonic() + 3
+            while not serials() - before and time.monotonic() < deadline:
+                time.sleep(.01)
+            odd_pane, = serials() - before
+            time.sleep(.5)
+            assert waiting.poll() is None, waiting.stderr.read()
+            client.remove(f'/pane/{odd_pane}')
+            assert waiting.wait(timeout=5) == 0
             # A name not there yet opens a pane named it, as acme's B does,
             # and Save creates it: git's and fish's temporary files are.
             fresh = root / 'wait new.txt'