Use script in the mypy repository to build wheels (#18)

This removes inline configuration and moves it to a script.
This makes it easier to have more complex logic during the build,
and also we can more easily test the build locally.

Also there's less need to understand the details of how GitHub actions
are configured.

Related to python/mypy#10074.

.github/workflows/build.yml

@@ -34,60 +34,8 @@ jobs:
           git checkout $COMMIT
           git submodule update --init --recursive
       - name: Build wheels
-        env:
-          CIBW_BUILD: "cp${{ matrix.python-version }}-*"
-          CIBW_SKIP: "*-manylinux_i686 *-win32"
-          CIBW_BUILD_VERBOSITY: 1
-
-          # mypy's isolated builds don't specify the requirements mypyc needs, so install
-          # requirements and don't use isolated builds. we need to use build-requirements.txt
-          # with recent mypy commits to get stub packages needed for compilation.
-          #
-          # TODO: remove use of mypy-requirements.txt once we no longer need to support
-          #       building pre modular typeshed releases
-          CIBW_BEFORE_BUILD: >
-            pip install -r {package}/mypy-requirements.txt &&
-            (pip install -r {package}/build-requirements.txt || true)
-          # download a copy of clang to use to compile on linux. this was probably built in 2018,
-          # speeds up compilation 2x
-          CIBW_BEFORE_BUILD_LINUX: >
-            (cd / && curl -L https://github.com/mypyc/mypy_mypyc-wheels/releases/download/llvm/llvm-centos-5.tar.gz | tar xzf -) &&
-            pip install -r {package}/mypy-requirements.txt &&
-            (pip install -r {package}/build-requirements.txt || true)
-
-          # the double negative is counterintuitive, https://github.com/pypa/pip/issues/5735
-          CIBW_ENVIRONMENT: >
-            MYPY_USE_MYPYC=1 MYPYC_OPT_LEVEL=3 PIP_NO_BUILD_ISOLATION=no
-          CIBW_ENVIRONMENT_LINUX: >
-            MYPY_USE_MYPYC=1 MYPYC_OPT_LEVEL=3 PIP_NO_BUILD_ISOLATION=no
-            CC=/opt/llvm/bin/clang
-          CIBW_ENVIRONMENT_WINDOWS: >
-            MYPY_USE_MYPYC=1 MYPYC_OPT_LEVEL=2 PIP_NO_BUILD_ISOLATION=no
-
-          # lxml is slow to build wheels for new releases, so allow installing reqs to fail
-          # if we failed to install lxml, we'll skip tests, but allow the build to succeed
-          CIBW_BEFORE_TEST: pip install -r {project}/mypy/test-requirements.txt || true
-          # pytest looks for configuration files in the parent directories of where the tests live.
-          # since we are trying to run the tests from their installed location, we copy those into
-          # the venv. Ew ew ew.
-          CIBW_TEST_COMMAND: >
-            ( ! pip list | grep lxml ) || (
-            DIR=$(python -c 'import mypy; from os.path import dirname; print(dirname(dirname(mypy.__path__[0])))')
-            && cp '{project}/mypy/pytest.ini' '{project}/mypy/conftest.py' $DIR
-            && MYPY_TEST_PREFIX='{project}/mypy' pytest $(python -c 'import mypy.test; print(mypy.test.__path__[0])')
-            )
-          # i ran into some flaky tests on windows, so only run testcheck. it looks like we
-          # previously didn't run any tests on windows wheels, so this is a net win.
-          CIBW_TEST_COMMAND_WINDOWS: >
-            bash -c "
-            ( ! pip list | grep lxml ) || (
-            DIR=$(python -c 'import mypy; from os.path import dirname; print(dirname(dirname(mypy.__path__[0])))')
-            && cp '{project}/mypy/pytest.ini' '{project}/mypy/conftest.py' $DIR
-            && MYPY_TEST_PREFIX='{project}/mypy' pytest $(python -c 'import mypy.test; print(mypy.test.__path__[0])')/testcheck.py
-            )
-            "
         run: |
-          python -m cibuildwheel --output-dir wheelhouse mypy
+          python mypy/misc/build_wheel.py --output-dir wheelhouse
       - uses: actions/upload-artifact@v2
         with:
           name: dist