test_sample.py

import pytest
import re
from six import PY2


def check_solaris_version(filename='/etc/release'):
    with open(filename) as f:
        content = f.readlines()
    for line in content:
        m = re.match(r'\s+Oracle Solaris (\d+\.\d+).*', line.rstrip())
        if m:
            return True
    return False


@pytest.fixture
def mocker_solaris(mocker):
    # Read a mocked /etc/release file
    mocked_etc_release_data = mocker.mock_open(read_data=" Oracle Solaris 12.0")
    builtin_open = "__builtin__.open" if PY2 else "builtins.open"
    mocker.patch(builtin_open, mocked_etc_release_data)


def test_check_solaris_version(mocker_solaris):
    assert check_solaris_version(filename='fakefile')