#!/usr/bin/env python
# Copyright (C) 2014  Codethink Limited
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

import unittest

import pip_find_deps
from pkg_resources import parse_requirements, parse_version

class ConflictDetectionTests(unittest.TestCase):

    def setUp(self):
        reqs = ['a == 0.1', 'a == 0.2']
        self.test_requirements = parse_requirements(reqs)

    # ('==', '0.1') conflicts with ('>', 0.1)
    # ('==', '0.1') conflicts with ('!=', 0.1)

    # ('<', '0.1') conflicts with ('>', '0.1')
    # ('<=', 0.1) conflicts with ('>=', 0.2)
    # ('<', '0.1') conflicts with ('>', '0.2')

    def test_eqs_two_different_versions(self):
        # ('==', '0.1') conflicts with ('==', '0.2')
        deps = pip_find_deps.resolve_version_constraints(
                            self.test_requirements)

        self.assertEqual(len(deps), 1)

        _, dep = deps.popitem()

        self.assertEqual(len(dep.conflicts), 1)
        self.assertEqual(dep.conflicts, [(('==', parse_version('0.1')),
                                         ('==', parse_version('0.2')))])

    def test_less_than(self):
        def run(requirements, expected_conflicts):
            deps = pip_find_deps.resolve_version_constraints(requirements)

            self.assertEqual(len(deps), 1)

            _, dep = deps.popitem()

            self.assertEqual(len(dep.conflicts), 1)
            self.assertEqual(dep.conflicts, expected_conflicts)

        def reverse(xs):
            return xs[::-1]

        requirements = list(parse_requirements(['a == 0.1', 'a < 0.1']))
        expected_conflicts = [(('==', parse_version('0.1')),
                              ('<', parse_version('0.1')))]

        # ('==', '0.1') conflicts with ('<', 0.1)
        run(requirements, expected_conflicts)

        # ('<', 0.1) conflicts with ('==', '0.1')
        run(reverse(requirements), reverse(expected_conflicts))


if __name__ == '__main__':
    suite = unittest.TestLoader().loadTestsFromTestCase(ConflictDetectionTests)
    unittest.TextTestRunner(verbosity=2).run(suite)