From 4abca7e1e7e2764faf20c7e677ea5c9ea9dbffe2 Mon Sep 17 00:00:00 2001 From: Paulo Neves Date: Tue, 26 Mar 2024 13:37:50 +0100 Subject: gh-98966: Handle stdout=subprocess.STDOUT (GH-98967) Explicitly handle the case where stdout=STDOUT as otherwise the existing error handling gets confused and reports hard to understand errors. Signed-off-by: Paulo Neves --- Lib/subprocess.py | 3 +++ Lib/test/test_subprocess.py | 7 +++++++ .../next/Library/2024-03-26-11-48-39.gh-issue-98966.SayV9y.rst | 2 ++ 3 files changed, 12 insertions(+) create mode 100644 Misc/NEWS.d/next/Library/2024-03-26-11-48-39.gh-issue-98966.SayV9y.rst diff --git a/Lib/subprocess.py b/Lib/subprocess.py index dbe1527..d7c7b45 100644 --- a/Lib/subprocess.py +++ b/Lib/subprocess.py @@ -839,6 +839,9 @@ class Popen: if not isinstance(bufsize, int): raise TypeError("bufsize must be an integer") + if stdout is STDOUT: + raise ValueError("STDOUT can only be used for stderr") + if pipesize is None: pipesize = -1 # Restore default if not isinstance(pipesize, int): diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py index 70452ca..9ecd842 100644 --- a/Lib/test/test_subprocess.py +++ b/Lib/test/test_subprocess.py @@ -1763,6 +1763,13 @@ class RunFuncTestCase(BaseTestCase): self.assertIn(b'BDFL', cp.stdout) self.assertIn(b'FLUFL', cp.stderr) + def test_stdout_stdout(self): + # run() refuses to accept stdout=STDOUT + with self.assertRaises(ValueError, + msg=("STDOUT can only be used for stderr")): + self.run_python("print('will not be run')", + stdout=subprocess.STDOUT) + def test_stdout_with_capture_output_arg(self): # run() refuses to accept 'stdout' with 'capture_output' tf = tempfile.TemporaryFile() diff --git a/Misc/NEWS.d/next/Library/2024-03-26-11-48-39.gh-issue-98966.SayV9y.rst b/Misc/NEWS.d/next/Library/2024-03-26-11-48-39.gh-issue-98966.SayV9y.rst new file mode 100644 index 0000000..e819a1e --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-03-26-11-48-39.gh-issue-98966.SayV9y.rst @@ -0,0 +1,2 @@ +In :mod:`subprocess`, raise a more informative message when +``stdout=STDOUT``. -- cgit v0.12