The `=` is better because it encourages folks to use the form that doesn't
suffer from issue #436 (https://bitbucket.org/hpk42/pytest/issue/436), which
can cause the arg to be treated as an "anchor" and used as the (unexpected)
path for searching for conftest.py files.
--HG--
branch : help_show_args_with_equals_instead_of_space