How to use the testpath.MockCommand function in testpath

def test_install_requires_extra(deps, extras, installed):
    it = InstallTests()
    try:
        it.setUp()
        ins = Installer.from_ini_path(samples_dir / 'extras' / 'pyproject.toml', python='mock_python',
                        user=False, deps=deps, extras=extras)

        cmd = MockCommand('mock_python')
        get_reqs = (
            "#!{python}\n"
            "import sys\n"
            "with open({recording_file!r}, 'wb') as w, open(sys.argv[-1], 'rb') as r:\n"
            "    w.write(r.read())"
        ).format(python=sys.executable, recording_file=cmd.recording_file)
        cmd.content = get_reqs

        with cmd as mock_py:
            ins.install_requirements()
        with open(mock_py.recording_file) as f:
            str_deps = f.read()
        deps = str_deps.split('\n') if str_deps else []

        assert set(deps) == installed
    finally:

def test_get_files_list_git(copy_sample):
    td = copy_sample('module1_toml')
    (td / '.git').mkdir()

    builder = sdist.SdistBuilder.from_ini_path(td / 'pyproject.toml')
    with MockCommand('git', LIST_FILES_GIT):
        files = builder.select_files()

    assert set(files) == {
        'foo', pjoin('dir1', 'bar'), pjoin('dir1', 'subdir', 'qux'),
        pjoin('dir2', 'abc')
    }

def test_get_files_list_hg(tmp_path):
    dir1 = tmp_path / 'dir1'
    copytree(str(samples_dir / 'module1_toml'), str(dir1))
    (tmp_path / '.hg').mkdir()
    builder = sdist.SdistBuilder.from_ini_path(dir1 / 'pyproject.toml')
    with MockCommand('hg', LIST_FILES_HG):
        files = builder.select_files()

    assert set(files) == {
        'bar', pjoin('subdir', 'qux')
    }

def test_build_wheel_only(copy_sample):
    td = copy_sample('module1_toml')
    (td / '.git').mkdir()  # Fake a git repo

    with MockCommand('git', LIST_FILES_TEMPLATE.format(
            python=sys.executable, module='module1.py')):
        res = build.main(td / 'pyproject.toml', formats={'wheel'})
    assert res.sdist is None

    # Compare str path to work around pathlib/pathlib2 mismatch on Py 3.5
    assert [str(p) for p in (td / 'dist').iterdir()] == [str(res.wheel.file)]

).format(python=sys.executable,
                           purelib=str(self.tmpdir / 'site-packages2'))

        # Called by Installer._get_dirs() :
        script2 = ("#!{python}\n"
                   "import json, sys\n"
                   "json.dump({{'purelib': {purelib!r}, 'scripts': {scripts!r} }}, "
                   "sys.stdout)"
                  ).format(python=sys.executable,
                           purelib=str(self.tmpdir / 'site-packages2'),
                           scripts=str(self.tmpdir / 'scripts2'))

        with MockCommand('mock_python', content=script1):
            ins = Installer.from_ini_path(samples_dir / 'package1' / 'pyproject.toml', python='mock_python',
                      symlink=True)
        with MockCommand('mock_python', content=script2):
            ins.install()

        assert_islink(self.tmpdir / 'site-packages2' / 'package1',
                      to=samples_dir / 'package1' / 'package1')
        assert_isfile(self.tmpdir / 'scripts2' / 'pkg_script')
        with (self.tmpdir / 'scripts2' / 'pkg_script').open() as f:
            assert f.readline().strip() == "#!mock_python"

def test_build_main(copy_sample):
    td = copy_sample('module1_toml')
    (td / '.git').mkdir()   # Fake a git repo

    with MockCommand('git', LIST_FILES_TEMPLATE.format(
            python=sys.executable, module='module1.py')):
        res = build.main(td / 'pyproject.toml')
    assert res.wheel.file.suffix == '.whl'
    assert res.sdist.file.name.endswith('.tar.gz')

    assert_isdir(td / 'dist')

def test_build_module_no_docstring():
    with TemporaryDirectory() as td:
        pyproject = Path(td, 'pyproject.toml')
        shutil.copy(str(samples_dir / 'no_docstring-pkg.toml'), str(pyproject))
        shutil.copy(str(samples_dir / 'no_docstring.py'), td)
        shutil.copy(str(samples_dir / 'EG_README.rst'), td)
        Path(td, '.git').mkdir()   # Fake a git repo


        with MockCommand('git', LIST_FILES_TEMPLATE.format(
                python=sys.executable, module='no_docstring.py')):
            with pytest.raises(common.NoDocstringError) as exc_info:
                build.main(pyproject)
            assert 'no_docstring.py' in str(exc_info.value)

def test_pip_install(self):
        ins = Installer.from_ini_path(samples_dir / 'package1' / 'pyproject.toml', python='mock_python',
                        user=False)

        with MockCommand('mock_python') as mock_py:
            ins.install()

        calls = mock_py.get_calls()
        assert len(calls) == 1
        cmd = calls[0]['argv']
        assert cmd[1:4] == ['-m', 'pip', 'install']
        assert cmd[4].endswith('package1')

def test_install_requires(self):
        ins = Installer.from_ini_path(samples_dir / 'requires-requests.toml',
                        user=False, python='mock_python')

        with MockCommand('mock_python') as mockpy:
            ins.install_requirements()
        calls = mockpy.get_calls()
        assert len(calls) == 1
        assert calls[0]['argv'][1:5] == ['-m', 'pip', 'install', '-r']

def test_build_sdist_only(copy_sample):
    td = copy_sample('module1_toml')
    (td / '.git').mkdir()  # Fake a git repo

    with MockCommand('git', LIST_FILES_TEMPLATE.format(
            python=sys.executable, module='module1.py')):
        res = build.main(td / 'pyproject.toml', formats={'sdist'})
    assert res.wheel is None

    # Compare str path to work around pathlib/pathlib2 mismatch on Py 3.5
    assert [str(p) for p in (td / 'dist').iterdir()] == [str(res.sdist.file)]