Forwarding pardes FILE for a new name in a directory it may not read or write is refused with words, not a pane that only fails at Save

A new name forwarded into a directory that is there but locked opened
an empty pane named for it, and the failure came only at its Save,
long after the launch. The directory is checked first: one that cannot
be read, written and entered is refused, exit 1, no pane made.

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

1 files changed, 13 insertions, 0 deletions

diff --git a/test/fs.py b/test/fs.py
index 8d830c48..0821b117 100644
--- a/test/fs.py
+++ b/test/fs.py
@@ -1403,6 +1403,19 @@ def test(binary, quic=False):
             # A pane address the session has not is refused in words, exit
             # 1, no pane made for a file of that name; one it has is looked
             # at. A name with a newline is said in words, not an error name.
+            # A new name in a directory there but not writable: refused now,
+            # not a pane that only fails at Save.
+            shut = root / 'shut-dir'
+            shut.mkdir()
+            shut.chmod(0o500)
+            try:
+                refused = subprocess.run([binary, 'shut-dir/new.txt'], cwd=root, env=env,
+                                         stdout=subprocess.PIPE, stderr=subprocess.PIPE, timeout=10)
+                assert refused.returncode == 1, refused
+                assert b'may not be read or written' in refused.stderr, refused.stderr
+                assert serials() == before, (serials(), before)
+            finally:
+                shut.chmod(0o755)
             for word, said in (('@p999:1', b'pardes: @p999:1: this session has no such pane'),
                                ('two\nlines.txt', b'a file name is one line')):
                 refused = subprocess.run([binary, word], cwd=root, env=env,