Replace importlib_metadata with importlib.metadata on Python 3.8+

[hroncok]

Fixes #5537

• Target the features branch

Unless your change is trivial or a small documentation fix (e.g., a typo or reword of a small section) please:

• Create a new changelog file in the changelog folder, with a name like <ISSUE NUMBER>.<TYPE>.rst. See changelog/README.rst for details.
• Add yourself to AUTHORS in alphabetical order;

I'm still running tox locally, there are some 3.8 failures, not yet sure if related.

[hroncok]

OK, the failures indeed seem related, yet I'll let the CI show them here, so we can figure out what's the actual problem.

Details

=================================================== FAILURES ====================================================
____________________________ TestGeneralUsage.test_early_load_setuptools_name[True] _____________________________

self = <acceptance_test.TestGeneralUsage object at 0x7f4036a209d0>
testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_early_load_setuptools_name0')>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4036a14820>, load_cov_early = True

    @pytest.mark.parametrize("load_cov_early", [True, False])
    def test_early_load_setuptools_name(self, testdir, monkeypatch, load_cov_early):
        testdir.makepyfile(mytestplugin1_module="")
        testdir.makepyfile(mytestplugin2_module="")
        testdir.makepyfile(mycov_module="")
        testdir.syspathinsert()
    
        loaded = []
    
        @attr.s
        class DummyEntryPoint:
            name = attr.ib()
            module = attr.ib()
            group = "pytest11"
    
            def load(self):
                __import__(self.module)
                loaded.append(self.name)
                return sys.modules[self.module]
    
        entry_points = [
            DummyEntryPoint("myplugin1", "mytestplugin1_module"),
            DummyEntryPoint("myplugin2", "mytestplugin2_module"),
            DummyEntryPoint("mycov", "mycov_module"),
        ]
    
        @attr.s
        class DummyDist:
            entry_points = attr.ib()
            files = ()
    
        def my_dists():
            return (DummyDist(entry_points),)
    
        monkeypatch.setattr(metadata, "distributions", my_dists)
        params = ("-p", "mycov") if load_cov_early else ()
        testdir.runpytest_inprocess(*params)
        if load_cov_early:
>           assert loaded == ["mycov", "myplugin1", "myplugin2"]
E           AssertionError: assert [] == ['mycov', 'myplugin1', 'myplugin2']
E             Right contains 3 more items, first extra item: 'mycov'
E             Use -v to get the full diff

.../pytest/testing/acceptance_test.py:148: AssertionError
--------------------------------------------- Captured stderr call ----------------------------------------------
Traceback (most recent call last):
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 544, in import_plugin
    __import__(importspec)
ModuleNotFoundError: No module named 'mycov'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/pytester.py", line 858, in runpytest_inprocess
    reprec = self.inline_run(*args, **kwargs)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/pytester.py", line 824, in inline_run
    ret = pytest.main(list(args), plugins=plugins)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 59, in main
    config = _prepareconfig(args, plugins)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 190, in _prepareconfig
    config = get_config(args)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 161, in get_config
    pluginmanager.consider_preparse(args)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 478, in consider_preparse
    self.consider_pluginarg(parg)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 503, in consider_pluginarg
    self.import_plugin(arg, consider_entry_points=True)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 552, in import_plugin
    raise new_exc.with_traceback(tb)
  File ".../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py", line 544, in import_plugin
    __import__(importspec)
ImportError: Error importing plugin "mycov": No module named 'mycov'
____________________________ TestGeneralUsage.test_early_load_setuptools_name[False] ____________________________

self = <acceptance_test.TestGeneralUsage object at 0x7f4037119a00>
testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_early_load_setuptools_name1')>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4037090850>, load_cov_early = False

    @pytest.mark.parametrize("load_cov_early", [True, False])
    def test_early_load_setuptools_name(self, testdir, monkeypatch, load_cov_early):
        testdir.makepyfile(mytestplugin1_module="")
        testdir.makepyfile(mytestplugin2_module="")
        testdir.makepyfile(mycov_module="")
        testdir.syspathinsert()
    
        loaded = []
    
        @attr.s
        class DummyEntryPoint:
            name = attr.ib()
            module = attr.ib()
            group = "pytest11"
    
            def load(self):
                __import__(self.module)
                loaded.append(self.name)
                return sys.modules[self.module]
    
        entry_points = [
            DummyEntryPoint("myplugin1", "mytestplugin1_module"),
            DummyEntryPoint("myplugin2", "mytestplugin2_module"),
            DummyEntryPoint("mycov", "mycov_module"),
        ]
    
        @attr.s
        class DummyDist:
            entry_points = attr.ib()
            files = ()
    
        def my_dists():
            return (DummyDist(entry_points),)
    
        monkeypatch.setattr(metadata, "distributions", my_dists)
        params = ("-p", "mycov") if load_cov_early else ()
        testdir.runpytest_inprocess(*params)
        if load_cov_early:
            assert loaded == ["mycov", "myplugin1", "myplugin2"]
        else:
>           assert loaded == ["myplugin1", "myplugin2", "mycov"]
E           AssertionError: assert [] == ['myplugin1', 'myplugin2', 'mycov']
E             Right contains 3 more items, first extra item: 'myplugin1'
E             Use -v to get the full diff

.../pytest/testing/acceptance_test.py:150: AssertionError
--------------------------------------------- Captured stdout call ----------------------------------------------
============================= test session starts ==============================
platform linux -- Python 3.8.0b1, pytest-5.0.1.dev17+g50b846e9d.d20190703, py-1.8.0, pluggy-0.12.0
hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('.../pytest/.hypothesis/examples')
rootdir: /tmp/pytest-of-churchyard/pytest-4/test_early_load_setuptools_name1
plugins: hypothesis-4.24.6
collected 0 items

========================= no tests ran in 0.00 seconds =========================
________________________ TestImportHookInstallation.test_installed_plugin_rewrite[plain] ________________________

self = <test_assertion.TestImportHookInstallation object at 0x7f4036e11310>
testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0')>, mode = 'plain'
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f403715ef10>

    @pytest.mark.parametrize("mode", ["plain", "rewrite"])
    def test_installed_plugin_rewrite(self, testdir, mode, monkeypatch):
        monkeypatch.delenv("PYTEST_DISABLE_PLUGIN_AUTOLOAD", raising=False)
        # Make sure the hook is installed early enough so that plugins
        # installed via setuptools are rewritten.
        testdir.tmpdir.join("hampkg").ensure(dir=1)
        contents = {
            "hampkg/__init__.py": """\
                import pytest
    
                @pytest.fixture
                def check_first2():
                    def check(values, value):
                        assert values.pop(0) == value
                    return check
            """,
            "spamplugin.py": """\
            import pytest
            from hampkg import check_first2
    
            @pytest.fixture
            def check_first():
                def check(values, value):
                    assert values.pop(0) == value
                return check
            """,
            "mainwrapper.py": """\
            import pytest, sys
            if sys.version_info >= (3, 8):
                from importlib import metadata
            else:
                import importlib_metadata as metadata
    
            class DummyEntryPoint(object):
                name = 'spam'
                module_name = 'spam.py'
                group = 'pytest11'
    
                def load(self):
                    import spamplugin
                    return spamplugin
    
            class DummyDistInfo(object):
                version = '1.0'
                files = ('spamplugin.py', 'hampkg/__init__.py')
                entry_points = (DummyEntryPoint(),)
                metadata = {'name': 'foo'}
    
            def distributions():
                return (DummyDistInfo(),)
    
            metadata.distributions = distributions
            pytest.main()
            """,
            "test_foo.py": """\
            def test(check_first):
                check_first([10, 30], 30)
    
            def test2(check_first2):
                check_first([10, 30], 30)
            """,
        }
        testdir.makepyfile(**contents)
        result = testdir.run(
            sys.executable, "mainwrapper.py", "-s", "--assert=%s" % mode
        )
        if mode == "plain":
            expected = "E       AssertionError"
        elif mode == "rewrite":
            expected = "*assert 10 == 30*"
        else:
            assert 0
>       result.stdout.fnmatch_lines([expected])
E       Failed: nomatch: 'E       AssertionError'
E           and: '============================= test session starts =============================='
E           and: 'platform linux -- Python 3.8.0b1, pytest-5.0.1.dev17+g50b846e9d.d20190703, py-1.8.0, pluggy-0.12.0'
E           and: "hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/.hypothesis/examples')"
E           and: 'rootdir: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0'
E           and: 'plugins: hypothesis-4.24.6'
E           and: 'collected 2 items'
E           and: ''
E           and: 'test_foo.py EE'
E           and: ''
E           and: '==================================== ERRORS ===================================='
E           and: '____________________________ ERROR at setup of test ____________________________'
E           and: 'file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py, line 1'
E           and: '  def test(check_first):'
E           and: "E       fixture 'check_first' not found"
E           and: '>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory'
E           and: ">       use 'pytest --fixtures [testpath]' for help on them."
E           and: ''
E           and: '/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py:1'
E           and: '___________________________ ERROR at setup of test2 ____________________________'
E           and: 'file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py, line 4'
E           and: '  def test2(check_first2):'
E           and: "E       fixture 'check_first2' not found"
E           and: '>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory'
E           and: ">       use 'pytest --fixtures [testpath]' for help on them."
E           and: ''
E           and: '/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py:4'
E           and: '=========================== 2 error in 0.02 seconds ============================'
E       remains unmatched: 'E       AssertionError'

.../pytest/testing/test_assertion.py:220: Failed
--------------------------------------------- Captured stdout call ----------------------------------------------
running: .../pytest/.tox/py38/bin/python mainwrapper.py -s --assert=plain
     in: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0
============================= test session starts ==============================
platform linux -- Python 3.8.0b1, pytest-5.0.1.dev17+g50b846e9d.d20190703, py-1.8.0, pluggy-0.12.0
hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/.hypothesis/examples')
rootdir: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0
plugins: hypothesis-4.24.6
collected 2 items

test_foo.py EE

==================================== ERRORS ====================================
____________________________ ERROR at setup of test ____________________________
file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py, line 1
  def test(check_first):
E       fixture 'check_first' not found
>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory
>       use 'pytest --fixtures [testpath]' for help on them.

/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py:1
___________________________ ERROR at setup of test2 ____________________________
file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py, line 4
  def test2(check_first2):
E       fixture 'check_first2' not found
>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory
>       use 'pytest --fixtures [testpath]' for help on them.

/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite0/test_foo.py:4
=========================== 2 error in 0.02 seconds ============================
_______________________ TestImportHookInstallation.test_installed_plugin_rewrite[rewrite] _______________________

self = <test_assertion.TestImportHookInstallation object at 0x7f4036e4e040>
testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1')>, mode = 'rewrite'
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4036bc9fd0>

    @pytest.mark.parametrize("mode", ["plain", "rewrite"])
    def test_installed_plugin_rewrite(self, testdir, mode, monkeypatch):
        monkeypatch.delenv("PYTEST_DISABLE_PLUGIN_AUTOLOAD", raising=False)
        # Make sure the hook is installed early enough so that plugins
        # installed via setuptools are rewritten.
        testdir.tmpdir.join("hampkg").ensure(dir=1)
        contents = {
            "hampkg/__init__.py": """\
                import pytest
    
                @pytest.fixture
                def check_first2():
                    def check(values, value):
                        assert values.pop(0) == value
                    return check
            """,
            "spamplugin.py": """\
            import pytest
            from hampkg import check_first2
    
            @pytest.fixture
            def check_first():
                def check(values, value):
                    assert values.pop(0) == value
                return check
            """,
            "mainwrapper.py": """\
            import pytest, sys
            if sys.version_info >= (3, 8):
                from importlib import metadata
            else:
                import importlib_metadata as metadata
    
            class DummyEntryPoint(object):
                name = 'spam'
                module_name = 'spam.py'
                group = 'pytest11'
    
                def load(self):
                    import spamplugin
                    return spamplugin
    
            class DummyDistInfo(object):
                version = '1.0'
                files = ('spamplugin.py', 'hampkg/__init__.py')
                entry_points = (DummyEntryPoint(),)
                metadata = {'name': 'foo'}
    
            def distributions():
                return (DummyDistInfo(),)
    
            metadata.distributions = distributions
            pytest.main()
            """,
            "test_foo.py": """\
            def test(check_first):
                check_first([10, 30], 30)
    
            def test2(check_first2):
                check_first([10, 30], 30)
            """,
        }
        testdir.makepyfile(**contents)
        result = testdir.run(
            sys.executable, "mainwrapper.py", "-s", "--assert=%s" % mode
        )
        if mode == "plain":
            expected = "E       AssertionError"
        elif mode == "rewrite":
            expected = "*assert 10 == 30*"
        else:
            assert 0
>       result.stdout.fnmatch_lines([expected])
E       Failed: nomatch: '*assert 10 == 30*'
E           and: '============================= test session starts =============================='
E           and: 'platform linux -- Python 3.8.0b1, pytest-5.0.1.dev17+g50b846e9d.d20190703, py-1.8.0, pluggy-0.12.0'
E           and: "hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/.hypothesis/examples')"
E           and: 'rootdir: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1'
E           and: 'plugins: hypothesis-4.24.6'
E           and: 'collected 2 items'
E           and: ''
E           and: 'test_foo.py EE'
E           and: ''
E           and: '==================================== ERRORS ===================================='
E           and: '____________________________ ERROR at setup of test ____________________________'
E           and: 'file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py, line 1'
E           and: '  def test(check_first):'
E           and: "E       fixture 'check_first' not found"
E           and: '>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory'
E           and: ">       use 'pytest --fixtures [testpath]' for help on them."
E           and: ''
E           and: '/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py:1'
E           and: '___________________________ ERROR at setup of test2 ____________________________'
E           and: 'file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py, line 4'
E           and: '  def test2(check_first2):'
E           and: "E       fixture 'check_first2' not found"
E           and: '>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory'
E           and: ">       use 'pytest --fixtures [testpath]' for help on them."
E           and: ''
E           and: '/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py:4'
E           and: '=========================== 2 error in 0.02 seconds ============================'
E       remains unmatched: '*assert 10 == 30*'

.../pytest/testing/test_assertion.py:220: Failed
--------------------------------------------- Captured stdout call ----------------------------------------------
running: .../pytest/.tox/py38/bin/python mainwrapper.py -s --assert=rewrite
     in: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1
============================= test session starts ==============================
platform linux -- Python 3.8.0b1, pytest-5.0.1.dev17+g50b846e9d.d20190703, py-1.8.0, pluggy-0.12.0
hypothesis profile 'default' -> database=DirectoryBasedExampleDatabase('/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/.hypothesis/examples')
rootdir: /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1
plugins: hypothesis-4.24.6
collected 2 items

test_foo.py EE

==================================== ERRORS ====================================
____________________________ ERROR at setup of test ____________________________
file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py, line 1
  def test(check_first):
E       fixture 'check_first' not found
>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory
>       use 'pytest --fixtures [testpath]' for help on them.

/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py:1
___________________________ ERROR at setup of test2 ____________________________
file /tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py, line 4
  def test2(check_first2):
E       fixture 'check_first2' not found
>       available fixtures: cache, capfd, capfdbinary, caplog, capsys, capsysbinary, doctest_namespace, monkeypatch, pytestconfig, record_property, record_testsuite_property, record_xml_attribute, recwarn, tmp_path, tmp_path_factory, tmpdir, tmpdir_factory
>       use 'pytest --fixtures [testpath]' for help on them.

/tmp/pytest-of-churchyard/pytest-4/test_installed_plugin_rewrite1/test_foo.py:4
=========================== 2 error in 0.02 seconds ============================
____________________________________ test_preparse_ordering_with_setuptools _____________________________________

self = <_pytest.config.PytestPluginManager object at 0x7f4037ca31c0>, modname = 'mytestplugin'
consider_entry_points = False

    def import_plugin(self, modname, consider_entry_points=False):
        """
        Imports a plugin with ``modname``. If ``consider_entry_points`` is True, entry point
        names are also considered to find a plugin.
        """
        # most often modname refers to builtin modules, e.g. "pytester",
        # "terminal" or "capture".  Those plugins are registered under their
        # basename for historic purposes but must be imported with the
        # _pytest prefix.
        assert isinstance(modname, str), (
            "module name as text required, got %r" % modname
        )
        modname = str(modname)
        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
            return
    
        importspec = "_pytest." + modname if modname in builtin_plugins else modname
        self.rewrite_hook.mark_rewrite(importspec)
    
        if consider_entry_points:
            loaded = self.load_setuptools_entrypoints("pytest11", name=modname)
            if loaded:
                return
    
        try:
>           __import__(importspec)
E           ModuleNotFoundError: No module named 'mytestplugin'

.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:544: ModuleNotFoundError

During handling of the above exception, another exception occurred:

testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_preparse_ordering_with_setuptools0')>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4036337e50>

    def test_preparse_ordering_with_setuptools(testdir, monkeypatch):
        monkeypatch.delenv("PYTEST_DISABLE_PLUGIN_AUTOLOAD", raising=False)
    
        class EntryPoint:
            name = "mytestplugin"
            group = "pytest11"
    
            def load(self):
                class PseudoPlugin:
                    x = 42
    
                return PseudoPlugin()
    
        class Dist:
            files = ()
            entry_points = (EntryPoint(),)
    
        def my_dists():
            return (Dist,)
    
        monkeypatch.setattr(metadata, "distributions", my_dists)
        testdir.makeconftest(
            """
            pytest_plugins = "mytestplugin",
        """
        )
        monkeypatch.setenv("PYTEST_PLUGINS", "mytestplugin")
>       config = testdir.parseconfig()

.../pytest/testing/test_config.py:553: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/pytester.py:913: in parseconfig
    config = _pytest.config._prepareconfig(args, self.plugins)
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:203: in _prepareconfig
    return pluginmanager.hook.pytest_cmdline_parse(
.../pytest/.tox/py38/lib/python3.8/site-packages/pluggy/hooks.py:289: in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
.../pytest/.tox/py38/lib/python3.8/site-packages/pluggy/manager.py:87: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
.../pytest/.tox/py38/lib/python3.8/site-packages/pluggy/manager.py:78: in <lambda>
    self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall(
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/helpconfig.py:89: in pytest_cmdline_parse
    config = outcome.get_result()
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:665: in pytest_cmdline_parse
    self.parse(args)
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:873: in parse
    self._preparse(args, addopts=addopts)
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:820: in _preparse
    self.pluginmanager.consider_env()
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:509: in consider_env
    self._import_plugin_specs(os.environ.get("PYTEST_PLUGINS"))
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:517: in _import_plugin_specs
    self.import_plugin(import_spec)
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:552: in import_plugin
    raise new_exc.with_traceback(tb)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <_pytest.config.PytestPluginManager object at 0x7f4037ca31c0>, modname = 'mytestplugin'
consider_entry_points = False

    def import_plugin(self, modname, consider_entry_points=False):
        """
        Imports a plugin with ``modname``. If ``consider_entry_points`` is True, entry point
        names are also considered to find a plugin.
        """
        # most often modname refers to builtin modules, e.g. "pytester",
        # "terminal" or "capture".  Those plugins are registered under their
        # basename for historic purposes but must be imported with the
        # _pytest prefix.
        assert isinstance(modname, str), (
            "module name as text required, got %r" % modname
        )
        modname = str(modname)
        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
            return
    
        importspec = "_pytest." + modname if modname in builtin_plugins else modname
        self.rewrite_hook.mark_rewrite(importspec)
    
        if consider_entry_points:
            loaded = self.load_setuptools_entrypoints("pytest11", name=modname)
            if loaded:
                return
    
        try:
>           __import__(importspec)
E           ImportError: Error importing plugin "mytestplugin": No module named 'mytestplugin'

.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:544: ImportError
_____________________________________ test_setuptools_importerror_issue1479 _____________________________________

testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_setuptools_importerror_issue14790')>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4036301d00>

    def test_setuptools_importerror_issue1479(testdir, monkeypatch):
        monkeypatch.delenv("PYTEST_DISABLE_PLUGIN_AUTOLOAD", raising=False)
    
        class DummyEntryPoint:
            name = "mytestplugin"
            group = "pytest11"
    
            def load(self):
                raise ImportError("Don't hide me!")
    
        class Distribution:
            version = "1.0"
            files = ("foo.txt",)
            entry_points = (DummyEntryPoint(),)
    
        def distributions():
            return (Distribution(),)
    
        monkeypatch.setattr(metadata, "distributions", distributions)
        with pytest.raises(ImportError):
>           testdir.parseconfig()
E           Failed: DID NOT RAISE <class 'ImportError'>

.../pytest/testing/test_config.py:578: Failed
____________________________ test_plugin_preparse_prevents_setuptools_loading[False] ____________________________

self = <_pytest.config.PytestPluginManager object at 0x7f4037d42f70>, modname = 'mytestplugin'
consider_entry_points = False

    def import_plugin(self, modname, consider_entry_points=False):
        """
        Imports a plugin with ``modname``. If ``consider_entry_points`` is True, entry point
        names are also considered to find a plugin.
        """
        # most often modname refers to builtin modules, e.g. "pytester",
        # "terminal" or "capture".  Those plugins are registered under their
        # basename for historic purposes but must be imported with the
        # _pytest prefix.
        assert isinstance(modname, str), (
            "module name as text required, got %r" % modname
        )
        modname = str(modname)
        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
            return
    
        importspec = "_pytest." + modname if modname in builtin_plugins else modname
        self.rewrite_hook.mark_rewrite(importspec)
    
        if consider_entry_points:
            loaded = self.load_setuptools_entrypoints("pytest11", name=modname)
            if loaded:
                return
    
        try:
>           __import__(importspec)
E           ModuleNotFoundError: No module named 'mytestplugin'

.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:544: ModuleNotFoundError

During handling of the above exception, another exception occurred:

testdir = <Testdir local('/tmp/pytest-of-churchyard/pytest-4/test_plugin_preparse_prevents_setuptools_loading1')>
monkeypatch = <_pytest.monkeypatch.MonkeyPatch object at 0x7f4037d42070>, block_it = False

    @pytest.mark.parametrize("block_it", [True, False])
    def test_plugin_preparse_prevents_setuptools_loading(testdir, monkeypatch, block_it):
        monkeypatch.delenv("PYTEST_DISABLE_PLUGIN_AUTOLOAD", raising=False)
    
        plugin_module_placeholder = object()
    
        class DummyEntryPoint:
            name = "mytestplugin"
            group = "pytest11"
    
            def load(self):
                return plugin_module_placeholder
    
        class Distribution:
            version = "1.0"
            files = ("foo.txt",)
            entry_points = (DummyEntryPoint(),)
    
        def distributions():
            return (Distribution(),)
    
        monkeypatch.setattr(metadata, "distributions", distributions)
        args = ("-p", "no:mytestplugin") if block_it else ()
        config = testdir.parseconfig(*args)
>       config.pluginmanager.import_plugin("mytestplugin")

.../pytest/testing/test_config.py:628: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:552: in import_plugin
    raise new_exc.with_traceback(tb)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

self = <_pytest.config.PytestPluginManager object at 0x7f4037d42f70>, modname = 'mytestplugin'
consider_entry_points = False

    def import_plugin(self, modname, consider_entry_points=False):
        """
        Imports a plugin with ``modname``. If ``consider_entry_points`` is True, entry point
        names are also considered to find a plugin.
        """
        # most often modname refers to builtin modules, e.g. "pytester",
        # "terminal" or "capture".  Those plugins are registered under their
        # basename for historic purposes but must be imported with the
        # _pytest prefix.
        assert isinstance(modname, str), (
            "module name as text required, got %r" % modname
        )
        modname = str(modname)
        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
            return
    
        importspec = "_pytest." + modname if modname in builtin_plugins else modname
        self.rewrite_hook.mark_rewrite(importspec)
    
        if consider_entry_points:
            loaded = self.load_setuptools_entrypoints("pytest11", name=modname)
            if loaded:
                return
    
        try:
>           __import__(importspec)
E           ImportError: Error importing plugin "mytestplugin": No module named 'mytestplugin'

.../pytest/.tox/py38/lib/python3.8/site-packages/_pytest/config/__init__.py:544: ImportError

[codecov]

Codecov Report

Merging #5539 into features will increase coverage by 0.02%.
The diff coverage is 71.42%.

@@             Coverage Diff              @@
##           features    #5539      +/-   ##
============================================
+ Coverage     96.08%   96.11%   +0.02%     
============================================
  Files           117      117              
  Lines         25695    25698       +3     
  Branches       2493     2494       +1     
============================================
+ Hits          24690    24699       +9     
+ Misses          701      695       -6     
  Partials        304      304

Impacted Files	Coverage Δ
src/_pytest/config/argparsing.py	88.2% <ø> (ø)	⬆️
testing/test_assertion.py	97.56% <ø> (ø)	⬆️
src/_pytest/config/__init__.py	94.62% <100%> (ø)	⬆️
testing/acceptance_test.py	98.03% <100%> (ø)	⬆️
testing/test_entry_points.py	100% <100%> (ø)	⬆️
testing/test_config.py	99.83% <100%> (ø)	⬆️
src/_pytest/compat.py	95.68% <33.33%> (-1.38%)	⬇️
src/_pytest/doctest.py	96.62% <0%> (+2.24%)	⬆️
src/_pytest/pastebin.py	91.22% <0%> (+3.5%)	⬆️

---

Continue to review full report at Codecov.

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[asottile]

the py38 failures make sense -- until pluggy has the fix it'll be using a hybrid of importlib.metadata and importlib_metadata

[hroncok]

I've tried with

pluggymaster: git+https://github.com/hroncok/pluggy.git@importlib_metadata

And that didn't work either :(

[nicoddemus]

Hmmm strange then.

Btw @hroncok this should target features. 👍

I will try to investigate this later too.

[hroncok]

retargeted

[nicoddemus]

Other than my comment, LGTM! 👍

[hroncok]

I'm hitting pytest: error: unrecognized arguments: -ra again. is it not fixed on features branch?

[nicoddemus]

Oh I'm afraid not... please cherry-pick 9021194 into your branch

[nicoddemus]

Oh you just did it 😅 👍

[hroncok]

(I have no idea how features vs. master works, so I've just cherrypicked it to be able to test it.)

[nicoddemus]

(I have no idea how features vs. master works, so I've just cherrypicked it to be able to test it.)

That's fine, thanks. master is meant for bug-fixes only, it is the branch used to release patch versions (next will be 5.0.1). features is for the next major/minor versions, so your PR will land in 5.1.0 only. 👍

[hroncok]

How are bugfixes usually forward-ported from master to features? is there a huge merge before release?

[nicoddemus]

How are bugfixes usually forward-ported from master to features?

We do that periodically and before a release, it just happens that this was not done before the short-option fix landed. 👍

[nicoddemus]

Thanks a ton @hroncok!

[nicoddemus]

@asottile want't to take a look or can we merge this?

[nicoddemus]

Thanks again @hroncok!