The `FDCapture`/`FDCaptureBinary` classes, used by `capfd`/`capfdbinary`
fixtures and the `--capture=fd` option (set by default), redirect FDs
1/2 (stdout/stderr) to a temporary file. To do this, they need to save
the old file by duplicating the FD before redirecting it, to be restored
once finished.
Previously, if this duplicating (`os.dup()`) failed, most likely due to
that FD being invalid, the FD redirection would silently not be done. The
FD capturing also performs python-level redirection (monkeypatching
`sys.stdout`/`sys.stderr`) which would still be done, but direct writes
to the FDs would fail.
This is not great. If pytest is run with `--capture=fd`, or a test is
using `capfd`, it expects writes to the FD to work and be captured,
regardless of external circumstances.
So, instead of disabling FD capturing, keep the redirection to a
temporary file, just don't restore it after closing, because there is
nothing to restore to.
Currently, a bad logging call, e.g.
logger.info('oops', 'first', 2)
triggers the default logging handling, which is printing an error to
stderr but otherwise continuing.
For regular programs this behavior makes sense, a bad log message
shouldn't take down the program. But during tests, it is better not to
skip over such mistakes, but propagate them to the user.
Previously, a LoggingCaptureHandler was instantiated for each test's
setup/call/teardown which turns out to be expensive.
Instead, only keep one instance and reset it between runs.
The tests came via c629f6b18 and c61ff31ffa.
The fixes from there are kind of obsoleted by 4cd08f9 (moving to importlib),
but it makes sense to keep them as integration tests in general.
The default message is often hard to read:
E _pytest.config.ConftestImportFailure: (local('D:\\projects\\pytest\\.tmp\\root\\foo\\conftest.py'), (<class 'RuntimeError'>, RuntimeError('some error',), <traceback object at 0x000001CCC3E39348>))
Using a shorter message is better:
E _pytest.config.ConftestImportFailure: RuntimeError: some error (from D:\projects\pytest\.tmp\root\foo\conftest.py)
And we don't really lose any information due to exception chaining.
Only filter with known failures, and explicitly keep paths of passed
arguments.
This also displays the "run-last-failure" status before collected files,
and does not update the cache with "--collect-only".
Fixes https://github.com/pytest-dev/pytest/issues/6968.
The previous commit made this possible, so utilize it.
Since legacy.py becomes pretty bare, I inlined it into __init__.py. I'm
not sure it's really "legacy" anyway!
Using a simple 50000 items benchmark with `--collect-only -k nomatch`:
Before (two commits ago):
======================== 50000 deselected in 10.31s =====================
19129345 function calls (18275596 primitive calls) in 10.634 seconds
Ordered by: cumulative time
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.001 0.001 2.270 2.270 __init__.py:149(pytest_collection_modifyitems)
1 0.036 0.036 2.270 2.270 __init__.py:104(deselect_by_keyword)
50000 0.055 0.000 2.226 0.000 legacy.py:87(matchkeyword)
After:
======================== 50000 deselected in 9.37s =========================
18029363 function calls (17175972 primitive calls) in 9.701 seconds
Ordered by: cumulative time
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.000 0.000 1.394 1.394 __init__.py:239(pytest_collection_modifyitems)
1 0.057 0.057 1.393 1.393 __init__.py:162(deselect_by_keyword)
The matching itself can be optimized more but that's a different story.
In current pytest, the same expression is matched against all items. But
it is re-parsed for every match.
Add support for "compiling" an expression and reusing the result. Errors
may only occur during compilation.
This is done by parsing the expression into a Python `ast.Expression`,
then `compile()`ing it into a code object. Evaluation is then done using
`eval()`.
Note: historically we used to use `eval` directly on the user input --
this is not the case here, the expression is entirely under our control
according to our grammar, we just JIT-compile it to Python as a
(completely safe) optimization.
New errors:
testing/test_setupplan.py:104:15: E741 ambiguous variable name 'l'
testing/test_setupplan.py:107:15: E741 ambiguous variable name 'l'
extra/get_issues.py:48:29: E741 ambiguous variable name 'l'
testing/test_error_diffs.py:270:32: E741 ambiguous variable name 'l'
Not so sure about it but easier to just fix.
But more importantly, is a large amount of typing-related issues there
were fixed which necessitated noqa's which can now be removed.
The `-k '-expr'` syntax is an old alias to `-k 'not expr'`. It's also
not a very convenient to have syntax that start with `-` on the CLI.
Deprecate it and suggest replacing with `not`.
---
The `-k 'expr:'` syntax discards all items until the first match and
keeps all subsequent, e.g. `-k foo` with
test_bar
test_foo
test_baz
results in `test_foo`, `test_baz`. That's a bit weird, so deprecate it
without a replacement. If someone complains we can reconsider or devise
a better alternative.
Running `pytest | head -1` and similar causes an annoying error to be
printed to stderr:
Exception ignored in: <_io.TextIOWrapper name='<stdout>' mode='w' encoding='utf-8'>
BrokenPipeError: [Errno 32] Broken pipe
(or possibly even a propagating exception in older/other Python versions).
The standard UNIX behavior is to handle the EPIPE silently. To
recommended method to do this in Python is described here:
https://docs.python.org/3/library/signal.html#note-on-sigpipe
It is not appropriate to apply this recommendation to `pytest.main()`,
which is used programmatically for in-process runs. Hence, change
pytest's entrypoint to a new `pytest.console_main()` function, to be
used exclusively by pytest's CLI, and add the SIGPIPE code there.
Fixes#4375.
