procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
stages:
- tests
image: registry.heptapod.net/mercurial/ci-images/mercurial-core:$HG_CI_IMAGE_TAG
variables:
PYTHON: python
TEST_HGMODULEPOLICY: "allow"
HG_CI_IMAGE_TAG: "v1.0"
TEST_HGTESTS_ALLOW_NETIO: "0"
.all_template: &all
when: on_success
.runtests_template: &runtests
<<: *all
stage: tests
# The runner made a clone as root.
# We make a new clone owned by user used to run the step.
before_script:
- hg clone . /tmp/mercurial-ci/ --noupdate --config phases.publish=no
- hg -R /tmp/mercurial-ci/ update `hg log --rev '.' --template '{node}'`
- cd /tmp/mercurial-ci/
- ls -1 tests/test-check-*.* > /tmp/check-tests.txt
- black --version
- clang-format --version
script:
- echo "python used, $PYTHON"
- echo "$RUNTEST_ARGS"
- HGTESTS_ALLOW_NETIO="$TEST_HGTESTS_ALLOW_NETIO" HGMODULEPOLICY="$TEST_HGMODULEPOLICY" "$PYTHON" tests/run-tests.py --color=always $RUNTEST_ARGS
checks:
<<: *runtests
variables:
RUNTEST_ARGS: "--time --test-list /tmp/check-tests.txt"
PYTHON: python3
rust-cargo-test:
<<: *all
stage: tests
script:
- echo "python used, $PYTHON"
- make rust-tests
variables:
PYTHON: python3
test-c:
<<: *runtests
variables:
RUNTEST_ARGS: " --no-rust --blacklist /tmp/check-tests.txt"
PYTHON: python3
TEST_HGMODULEPOLICY: "c"
TEST_HGTESTS_ALLOW_NETIO: "1"
test-pure:
<<: *runtests
variables:
RUNTEST_ARGS: "--pure --blacklist /tmp/check-tests.txt"
PYTHON: python3
TEST_HGMODULEPOLICY: "py"
test-rust:
<<: *runtests
variables:
HGWITHRUSTEXT: cpython
RUNTEST_ARGS: "--rust --blacklist /tmp/check-tests.txt"
PYTHON: python3
TEST_HGMODULEPOLICY: "rust+c"
test-rhg:
<<: *runtests
variables:
HGWITHRUSTEXT: cpython
RUNTEST_ARGS: "--rust --rhg --blacklist /tmp/check-tests.txt"
PYTHON: python3
TEST_HGMODULEPOLICY: "rust+c"
test-chg:
<<: *runtests
variables:
PYTHON: python3
RUNTEST_ARGS: "--blacklist /tmp/check-tests.txt --chg"
TEST_HGMODULEPOLICY: "c"
check-pytype:
extends: .runtests_template
before_script:
- hg clone . /tmp/mercurial-ci/ --noupdate --config phases.publish=no
- hg -R /tmp/mercurial-ci/ update `hg log --rev '.' --template '{node}'`
- cd /tmp/mercurial-ci/
- make local PYTHON=$PYTHON
- $PYTHON -m pip install --user -U pytype==2021.04.15
variables:
RUNTEST_ARGS: " --allow-slow-tests tests/test-check-pytype.t"
HGTEST_SLOWTIMEOUT: "3600"
PYTHON: python3
TEST_HGMODULEPOLICY: "c"
# `sh.exe --login` sets a couple of extra environment variables that are defined
# in the MinGW shell, but switches CWD to /home/$username. The previous value
# is stored in OLDPWD. Of the added variables, MSYSTEM is crucial to running
# run-tests.py- it is needed to make run-tests.py generate a `python3` script
# that satisfies the various shebang lines and delegates to `py -3`.
.window_runtests_template: &windows_runtests
<<: *all
when: manual # we don't have any Windows runners anymore at the moment
stage: tests
before_script:
- C:/MinGW/msys/1.0/bin/sh.exe --login -c 'cd "$OLDPWD" && ls -1 tests/test-check-*.* > C:/Temp/check-tests.txt'
# TODO: find/install cvs, bzr, perforce, gpg, sqlite3
script:
- echo "Entering script section"
- echo "python used, $Env:PYTHON"
- Invoke-Expression "$Env:PYTHON -V"
- Invoke-Expression "$Env:PYTHON -m black --version"
- echo "$Env:RUNTEST_ARGS"
- echo "$Env:TMP"
- echo "$Env:TEMP"
- C:/MinGW/msys/1.0/bin/sh.exe --login -c 'cd "$OLDPWD" && HGTESTS_ALLOW_NETIO="$TEST_HGTESTS_ALLOW_NETIO" HGMODULEPOLICY="$TEST_HGMODULEPOLICY" $PYTHON tests/run-tests.py --color=always $RUNTEST_ARGS'
windows:
<<: *windows_runtests
tags:
- windows
variables:
TEST_HGMODULEPOLICY: "c"
RUNTEST_ARGS: "--blacklist C:/Temp/check-tests.txt"
PYTHON: py -3
windows-pyox:
<<: *windows_runtests
tags:
- windows
variables:
TEST_HGMODULEPOLICY: "c"
RUNTEST_ARGS: "--blacklist C:/Temp/check-tests.txt --pyoxidized"
PYTHON: py -3