contrib/packaging/build-linux-wheels.sh

resolve: use the `parentchange` context manager to apply merge action

In an ideal world, we would not have to do that. However, we are miles away from
being ready to not have to do it.

So we add this context manager alongside a long comment. This will help use to
get to the point were have two distinct API with strict rules about when to call
them.

Differential Revision: https://phab.mercurial-scm.org/D11074

#!/bin/bash
# This file is directly inspired by
# https://github.com/pypa/python-manylinux-demo/blob/master/travis/build-wheels.sh
set -e -x

PYTHON_TARGETS=$(ls -d /opt/python/cp27*/bin)

# Create an user for the tests
useradd hgbuilder

# Bypass uid/gid problems
cp -R /src /io && chown -R hgbuilder:hgbuilder /io

# Compile wheels for Python 2.X
for PYBIN in $PYTHON_TARGETS; do
    "${PYBIN}/pip" wheel /io/ -w wheelhouse/
done

# Bundle external shared libraries into the wheels with
# auditwheel (https://github.com/pypa/auditwheel) repair.
# It also fix the ABI tag on the wheel making it pip installable.
for whl in wheelhouse/*.whl; do
    auditwheel repair "$whl" -w /src/wheelhouse/
done

# Install packages and run the tests for all Python versions
cd /io/tests/

for PYBIN in $PYTHON_TARGETS; do
    # Install mercurial wheel as root
    "${PYBIN}/pip" install mercurial --no-index -f /src/wheelhouse
    # But run tests as hgbuilder user (non-root)
    su hgbuilder -c "\"${PYBIN}/python\" /io/tests/run-tests.py --with-hg=\"${PYBIN}/hg\" --blacklist=/io/contrib/packaging/linux-wheel-centos5-blacklist"
done