From 7d61c967c9663d12deb7c7de2b48e17d6041308d Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@python.org>
Date: Wed, 28 Jun 2023 04:26:52 +0200
Subject: [PATCH] gh-101634: regrtest reports decoding error as failed test
 (#106169)

When running the Python test suite with -jN option, if a worker stdout
cannot be decoded from the locale encoding report a failed testn so the
exitcode is non-zero.

(cherry picked from commit 2ac3eec103cf450aaaebeb932e51155d2e7fb37b)
---
 Lib/test/libregrtest/runtest_mp.py            | 12 ++++++-
 Lib/test/test_regrtest.py                     | 36 +++++++++++++++++++
 ...-06-28-02-51-08.gh-issue-101634.Rayczr.rst |  3 ++
 3 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Tests/2023-06-28-02-51-08.gh-issue-101634.Rayczr.rst

diff --git a/Lib/test/libregrtest/runtest_mp.py b/Lib/test/libregrtest/runtest_mp.py
index c6a4dae2df86a9..8587e64e5153e6 100644
--- a/Lib/test/libregrtest/runtest_mp.py
+++ b/Lib/test/libregrtest/runtest_mp.py
@@ -269,6 +269,7 @@ def _runtest(self, test_name: str) -> MultiprocessResult:
             encoding = locale.getencoding()
         else:
             encoding = sys.stdout.encoding
+
         # gh-94026: Write stdout+stderr to a tempfile as workaround for
         # non-blocking pipes on Emscripten with NodeJS.
         with tempfile.TemporaryFile('w+', encoding=encoding) as stdout_fh:
@@ -277,7 +278,14 @@ def _runtest(self, test_name: str) -> MultiprocessResult:
             # Python finalization: too late for libregrtest.
             retcode = self._run_process(test_name, stdout_fh)
             stdout_fh.seek(0)
-            stdout = stdout_fh.read().strip()
+
+            try:
+                stdout = stdout_fh.read().strip()
+            except Exception as exc:
+                # gh-101634: Catch UnicodeDecodeError if stdout cannot be
+                # decoded from encoding
+                err_msg = f"Cannot read process stdout: {exc}"
+                return self.mp_result_error(ChildError(test_name), '', err_msg)
 
         if retcode is None:
             return self.mp_result_error(Timeout(test_name), stdout)
@@ -452,6 +460,8 @@ def _process_result(self, item: QueueOutput) -> bool:
             # Thread got an exception
             format_exc = item[1]
             print_warning(f"regrtest worker thread failed: {format_exc}")
+            result = ChildError("<regrtest worker>")
+            self.regrtest.accumulate_result(result)
             return True
 
         self.test_index += 1
diff --git a/Lib/test/test_regrtest.py b/Lib/test/test_regrtest.py
index f692dd1e3e65b4..78552590a7289c 100644
--- a/Lib/test/test_regrtest.py
+++ b/Lib/test/test_regrtest.py
@@ -7,6 +7,7 @@
 import contextlib
 import glob
 import io
+import locale
 import os.path
 import platform
 import re
@@ -1518,6 +1519,41 @@ def test_cleanup(self):
         for name in names:
             self.assertFalse(os.path.exists(name), name)
 
+    def test_mp_decode_error(self):
+        # gh-101634: If a worker stdout cannot be decoded, report a failed test
+        # and a non-zero exit code.
+        if sys.platform == 'win32':
+            encoding = locale.getencoding()
+        else:
+            encoding = sys.stdout.encoding
+            if encoding is None:
+                encoding = sys.__stdout__.encoding
+                if encoding is None:
+                    self.skipTest(f"cannot get regrtest worker encoding")
+
+        nonascii = b"byte:\xa0\xa9\xff\n"
+        try:
+            nonascii.decode(encoding)
+        except UnicodeDecodeError:
+            pass
+        else:
+            self.skipTest(f"{encoding} can decode non-ASCII bytes {nonascii!a}")
+
+        code = textwrap.dedent(fr"""
+            import sys
+            # bytes which cannot be decoded from UTF-8
+            nonascii = {nonascii!a}
+            sys.stdout.buffer.write(nonascii)
+            sys.stdout.buffer.flush()
+        """)
+        testname = self.create_test(code=code)
+
+        output = self.run_tests("--fail-env-changed", "-v", "-j1", testname,
+                                exitcode=EXITCODE_BAD_TEST)
+        self.check_executed_tests(output, [testname],
+                                  failed=[testname],
+                                  randomize=True)
+
 
 class TestUtils(unittest.TestCase):
     def test_format_duration(self):
diff --git a/Misc/NEWS.d/next/Tests/2023-06-28-02-51-08.gh-issue-101634.Rayczr.rst b/Misc/NEWS.d/next/Tests/2023-06-28-02-51-08.gh-issue-101634.Rayczr.rst
new file mode 100644
index 00000000000000..6fbfc84c19e1b8
--- /dev/null
+++ b/Misc/NEWS.d/next/Tests/2023-06-28-02-51-08.gh-issue-101634.Rayczr.rst
@@ -0,0 +1,3 @@
+When running the Python test suite with ``-jN`` option, if a worker stdout
+cannot be decoded from the locale encoding report a failed testn so the
+exitcode is non-zero. Patch by Victor Stinner.

<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.0 Transitional//EN' 'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'>
<html xmlns='http://www.w3.org/1999/xhtml'>
<head>
<title>pFad - Phonifier reborn</title>
<meta http-equiv='Content-Type' content='text/html; charset=utf-8' />
</head>
<body>
<h1>Pfad - The Proxy pFad of &#169; 2024 Garber Painting. All rights reserved.</h1>


<!-- Disclaimer -->
<p>Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.</p>
<br>
<p>Alternative Proxies:</p><p><a href="http://rainy.clevelandohioweatherforecast.com/php-proxy/index.php?q=https://patch-diff.githubusercontent.com/raw/python/cpython/pull/106175.patch" target="_blank">Alternative Proxy</a></p><p><a href="http://rainy.clevelandohioweatherforecast.com/pFad/index.php?u=https://patch-diff.githubusercontent.com/raw/python/cpython/pull/106175.patch" target="_blank">pFad Proxy</a></p><p><a href="http://rainy.clevelandohioweatherforecast.com/pFad/v3index.php?u=https://patch-diff.githubusercontent.com/raw/python/cpython/pull/106175.patch" target="_blank">pFad v3 Proxy</a></p><p><a href="http://rainy.clevelandohioweatherforecast.com/pFad/v4index.php?u=https://patch-diff.githubusercontent.com/raw/python/cpython/pull/106175.patch" target="_blank">pFad v4 Proxy</a></p></body>
</html>