test_extension_setup_errors[dotnetexample-override_conf2-AutoAPI fails with no internet

[mjsir911]

Hi,

I'm packaging sphinx-autoapi for gentoo and in the process of testing it with a network sandbox I'm having trouble getting a test to pass without the optional dotnet package installed & no internet access to autodownload:

Test failures

================================================ FAILURES ================================================
_ TestExtensionErrors.test_extension_setup_errors[dotnetexample-override_conf2-AutoAPI of type `dotnet` requires following packages to be installed and included in extensions list: sphinxcontrib.dotnetdomain (available as "sphinxcontrib-dotnetdomain" on PyPI)] _

self = <test_integration.TestExtensionErrors object at 0x7fbd892d40a0>, proj_name = 'dotnetexample'
override_conf = {'autoapi_type': 'dotnet', 'extensions': ['autoapi.extension']}
err_msg = 'AutoAPI of type `dotnet` requires following packages to be installed and included in extensions list: sphinxcontrib.dotnetdomain (available as "sphinxcontrib-dotnetdomain" on PyPI)'

    @pytest.mark.parametrize(
        "proj_name, override_conf, err_msg",
        [
            (
                "toctreeexample",
                {"autoapi_type": "INVALID VALUE"},
                (
                    "Invalid autoapi_type setting, following values is "
                    'allowed: "dotnet", "go", "javascript", "python"'
                ),
            ),
            (
                "goexample",
                {"autoapi_type": "go", "extensions": ["autoapi.extension"]},
                (
                    "AutoAPI of type `go` requires following "
                    "packages to be installed and included in extensions list: "
                    "sphinxcontrib.golangdomain (available as "
                    '"sphinxcontrib-golangdomain" on PyPI)'
                ),
            ),
            (
                "dotnetexample",
                {"autoapi_type": "dotnet", "extensions": ["autoapi.extension"]},
                (
                    "AutoAPI of type `dotnet` requires following "
                    "packages to be installed and included in extensions list: "
                    "sphinxcontrib.dotnetdomain (available as "
                    '"sphinxcontrib-dotnetdomain" on PyPI)'
                ),
            ),
        ],
    )
    def test_extension_setup_errors(self, proj_name, override_conf, err_msg):
        with pytest.raises(ExtensionError) as err_info:
            with sphinx_build(proj_name, override_conf):
                pass
    
>       assert str(err_info.value) == err_msg
E       assert ('AutoAPI Directory '\n '`/var/tmp/portage/dev-python/sphinx-autoapi-1.8.4/work/sphinx-autoapi-1.8.4/tests/dotnetexample/example/Identity/src` '\n 'not found. Please check your `autoapi_dirs` setting.') == ('AutoAPI of type `dotnet` requires following packages to be installed and '\n 'included in extensions list: sphinxcontrib.dotnetdomain (available as '\n '"sphinxcontrib-dotnetdomain" on PyPI)')
E         - AutoAPI of type `dotnet` requires following packages to be installed and included in extensions list: sphinxcontrib.dotnetdomain (available as "sphinxcontrib-dotnetdomain" on PyPI)
E         + AutoAPI Directory `/var/tmp/portage/dev-python/sphinx-autoapi-1.8.4/work/sphinx-autoapi-1.8.4/tests/dotnetexample/example/Identity/src` not found. Please check your `autoapi_dirs` setting.

err_info   = <ExceptionInfo ExtensionError('AutoAPI Directory `/var/tmp/portage/dev-python/sphinx-autoapi-1.8.4/work/sphinx-autoapi-1.8.4/tests/dotnetexample/example/Identity/src` not found. Please check your `autoapi_dirs` setting.') tblen=7>
err_msg    = ('AutoAPI of type `dotnet` requires following packages to be installed and '
 'included in extensions list: sphinxcontrib.dotnetdomain (available as '
 '"sphinxcontrib-dotnetdomain" on PyPI)')
override_conf = {'autoapi_type': 'dotnet', 'extensions': ['autoapi.extension']}
proj_name  = 'dotnetexample'
self       = <test_integration.TestExtensionErrors object at 0x7fbd892d40a0>

tests/test_integration.py:170: AssertionError
------------------------------------------ Captured stdout call ------------------------------------------
Running Sphinx v4.3.2
making output directory... done
------------------------------------------ Captured stderr call ------------------------------------------
Cloning into '/var/tmp/portage/dev-python/sphinx-autoapi-1.8.4/work/sphinx-autoapi-1.8.4/tests/dotnetexample/example/Identity'...
fatal: unable to access 'https://github.com/aspnet/Identity/': Could not resolve host: github.com

To reproduce:

1. clone repository
2. make sure sphinxcontrib-dotnetdomain is not installed
3. install dependencies necessary to pass tests (other than sphinxcontrib-dotnetdomain)
4. turn off internet
5. python3.8 -m pytest -vv -ra -l -Wdefault --color=yes -p no:cov -p no:flake8 -p no:flakes -p no:pylint

[AWhetter]

Closing this now that we are dropping support for documenting languages other than Python. See #248 for more information on this decision.