[Pytest-commit] Issue #472: skipif documentation has broken example using pytest.config (hpk42/pytest)

[Wichert Akkerman]

New issue 472: skipif documentation has broken example using pytest.config
https://bitbucket.org/hpk42/pytest/issue/472/skipif-documentation-has-broken-example

Wichert Akkerman:

The [skip and xfail](https://pytest.org/latest/skipping.html) documentation has an example at the end of the page showing how to use ```pytest.config`` to make a skip conditional on the test runner configuration:

```
@pytest.mark.skipif(not pytest.config.getvalue("db"),
                    reason="--db was not specified")
def test_function(...):
    pass
```

I tried to use that mechanism to make a test conditional on the use of PostgreSQL with tests:

```
def pytest_generate_tests(metafunc):
    if 'sqlalchemy_url' in metafunc.fixturenames:
        metafunc.parametrize('sqlalchemy_url', [metafunc.config.option.database])

require_postgres = pytest.mark.skipif(
        not pytest.config.getvalue('database').startswith('postgresql'),
        reason='PostgreSQL database required')
```

When I try to run my tests with this I get the following error:

```
Traceback (most recent call last):
  File "bin/py.test", line 62, in <module>
    sys.exit(pytest.main())
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 19, in main
    config = _prepareconfig(args, plugins)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 63, in _prepareconfig
    pluginmanager=pluginmanager, args=args)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 377, in __call__
    return self._docall(methods, kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 388, in _docall
    res = mc.execute()
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 289, in execute
    res = method(**kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/helpconfig.py", line 27, in pytest_cmdline_parse
    config = __multicall__.execute()
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 289, in execute
    res = method(**kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 618, in pytest_cmdline_parse
    self.parse(args)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 711, in parse
    self._preparse(args)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 691, in _preparse
    args=args, parser=self._parser)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 377, in __call__
    return self._docall(methods, kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 388, in _docall
    res = mc.execute()
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 289, in execute
    res = method(**kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/capture.py", line 83, in pytest_load_initial_conftests
    return __multicall__.execute()
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/core.py", line 289, in execute
    res = method(**kwargs)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 674, in pytest_load_initial_conftests
    self._conftest.setinitial(args)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 487, in setinitial
    self._try_load_conftest(anchor)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 493, in _try_load_conftest
    self._path2confmods[None] = self.getconftestmodules(anchor)
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 512, in getconftestmodules
    clist.append(self.importconftest(conftestpath))
  File "/Users/wichert/Library/buildout/eggs/pytest-2.5.2-py2.7.egg/_pytest/config.py", line 538, in importconftest
    self._conftestpath2mod[conftestpath] = mod = conftestpath.pyimport()
  File "/Users/wichert/Library/buildout/eggs/py-1.4.20-py2.7.egg/py/_path/local.py", line 608, in pyimport
    __import__(pkgpath.basename)
  File "/Users/wichert/myapp/tests/__init__.py", line 5, in <module>
    not pytest.config.getvalue('database').startswith('postgres'),
AttributeError: 'module' object has no attribute 'config'
```