fix bare "py.test" runs without a directory by not defaulting to --doctest-modules which will virtually import everything

bench/bench.py

@@ -1,9 +1,10 @@
 
-import cProfile
-import py
-import pstats
-stats = cProfile.run('py.test.cmdline.main(["empty.py", ])', 'prof')
-p = pstats.Stats("prof")
-p.strip_dirs()
-p.sort_stats('cumulative')
-print p.print_stats(30)
+if __name__ == '__main__':
+    import cProfile
+    import py
+    import pstats
+    stats = cProfile.run('py.test.cmdline.main(["empty.py", ])', 'prof')
+    p = pstats.Stats("prof")
+    p.strip_dirs()
+    p.sort_stats('cumulative')
+    print p.print_stats(30)

tox.ini

@@ -63,6 +63,6 @@ commands=
 [pytest]
 minversion=2.0
 plugins=pytester
-addopts= -rxf --pyargs --doctest-modules
+addopts= -rxf --pyargs
 rsyncdirs=tox.ini pytest.py _pytest testing