check-py3-compat: manually format and print warnings
The warnings mechanism may print to stderr on Python 3. Independent buffering
of stdout and stderr can lead to warnings output not being printed properly.
This commit traps warnings when executing individual files and prints
warnings to stdout so output is deterministic.
Differential Revision: https://phab.mercurial-scm.org/D5845
--- a/contrib/check-py3-compat.py Mon Feb 04 14:25:00 2019 -0800
+++ b/contrib/check-py3-compat.py Mon Feb 04 14:38:23 2019 -0800
@@ -14,6 +14,7 @@
import os
import sys
import traceback
+import warnings
def check_compat_py2(f):
"""Check Python 3 compatibility for a file with Python 2"""
@@ -91,6 +92,11 @@
fn = check_compat_py3
for f in sys.argv[1:]:
- fn(f)
+ with warnings.catch_warnings(record=True) as warns:
+ fn(f)
+
+ for w in warns:
+ print(warnings.formatwarning(w.message, w.category,
+ w.filename, w.lineno).rstrip())
sys.exit(0)