From ebf44d523bc8f785cc7c0aaacb7d424fb77c3d4a Mon Sep 17 00:00:00 2001
From: Abdessamad Derraz <3028866+Abdess@users.noreply.github.com>
Date: Sun, 18 Oct 2026 08:23:38 +0200
Subject: [PATCH] fix: make the closed-pipe test meet a full pipe

---
 tests/test_audit_regressions.py | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/tests/test_audit_regressions.py b/tests/test_audit_regressions.py
index 8b483d2a..dd019b4e 100644
--- a/tests/test_audit_regressions.py
+++ b/tests/test_audit_regressions.py
@@ -3839,6 +3839,15 @@ class AReaderThatLeavesEarlyIsNoCrash(unittest.TestCase):
             [sys.executable, "scripts/verify.py", "--list-emulators"], cwd=ROOT,
             stdout=subprocess.PIPE, stderr=subprocess.PIPE,
         )
+        # The listing fits a 64 KiB pipe: a child that wrote it all before
+        # the close below never met the broken pipe and exited 0. A 4 KiB
+        # pipe keeps it writing when the reader leaves.
+        try:
+            import fcntl  # noqa: PLC0415
+
+            fcntl.fcntl(proc.stdout.fileno(), fcntl.F_SETPIPE_SZ, 4096)
+        except (ImportError, AttributeError, OSError):
+            pass
         proc.stdout.readline()
         proc.stdout.close()
         _, err = proc.communicate(timeout=120)