make usefixtures appear in py.test --markers output

_pytest/__init__.py

@@ -1,2 +1,2 @@
 #
-__version__ = '2.3.0.dev32'
+__version__ = '2.3.0.dev33'

_pytest/python.py

@@ -101,6 +101,10 @@ def pytest_configure(config):
         "@parametrize('arg1', [1,2]) would lead to two calls of the decorated "
         "test function, one with arg1=1 and another with arg1=2."
     )
+    config.addinivalue_line("markers",
+        "usefixtures(fixturename1, fixturename2, ...): mark tests as needing "
+        "all of the specified fixtures."
+    )
 
 def pytest_sessionstart(session):
     session._fixturemanager = FixtureManager(session)

setup.py

@@ -24,7 +24,7 @@ def main():
         name='pytest',
         description='py.test: simple powerful testing with Python',
         long_description = long_description,
-        version='2.3.0.dev32',
+        version='2.3.0.dev33',
         url='http://pytest.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],

testing/test_python.py

@@ -1445,6 +1445,12 @@ class TestMetafuncFunctional:
         reprec = testdir.inline_run()
         reprec.assertoutcome(passed=1)
 
+    def test_usefixtures_seen_in_showmarkers(self, testdir):
+        result = testdir.runpytest("--markers")
+        result.stdout.fnmatch_lines("""
+            *usefixtures(fixturename1*mark tests*fixtures*
+        """)
+
     def test_generate_tests_only_done_in_subdir(self, testdir):
         sub1 = testdir.mkpydir("sub1")
         sub2 = testdir.mkpydir("sub2")