def test_double_install_fail(script, data):
 result = script.pip('install', 'pip==*', 'pip==7.1.2', expect_error=True)
 msg = "Double requirement given: pip==7.1.2 (already in pip==*, name='pip')"
 assert (msg in result.stderr)

def test_double_install_fail ( script , data ) : result = script . pip ( 'install' , 'pip==*' , 'pip==7.1.2' , expect_error = True ) msg = "Double requirement given: pip==7.1.2 (already in pip==*, name='pip')" assert ( msg in result . stderr )
test double install failing with two different version requirements .