[Pytest-commit] Issue #594: py.test with xdist is not executing tests parametrized with random values (hpk42/pytest)

[pytry]

New issue 594: py.test with xdist is not executing tests parametrized with random values
https://bitbucket.org/hpk42/pytest/issue/594/pytest-with-xdist-is-not-executing-tests

pytry:

I have noticed the following strange behaviour for pytest and xdist.

When trying to run the test that is parametrized with some randomly selected values the test are not actually run. The same test is executed without any problems if xdist is not used.

Following code can be used to reproduce this.

```
#!python
import pytest
import random

PARAMS_NUMBER = 3
PARAMS = []

for i in range(PARAMS_NUMBER):
    PARAMS.append(random.randrange(0, 1000))

@pytest.mark.parametrize('rand_par', PARAMS)
def test_random_param(rand_par):

    assert 500 > rand_par

```

Without xdists it works fine.

With xdist no test is executed at all with the following output


```
#!console
============================= test session starts =============================
platform win32 -- Python 2.7.3 -- py-1.4.24 -- pytest-2.6.2
plugins: xdist
gw0 [3] / gw1 [3] / gw2 [3] / gw3 [3]
scheduling tests via LoadScheduling

==============================  in 1.93 seconds ===============================

```

Versions I'm using:

    python 2.7.3
    pytest 2.6.2
    pytest-xdist 1.11

Additional note:

With some older versions (xdist 1.8 and pytest 2.4.X or 2.5.X do not remember exactly) the xdist was stopping on assertion in dsession.py

```
#!python
assert collection == col

```

Thanks in advance for any help :)