#!/usr/bin/env python3
#
# Copyright (c) 2016-present, Facebook, Inc.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree. An additional grant
# of patent rights can be found in the PATENTS file in the same directory.

import os

from .lib.hg_extension_test_base import hg_test
from ..lib import hgrepo


@hg_test
class GraftTest:
    def populate_backing_repo(self, repo):
        repo.write_file('first.txt', '1')
        self.commit1 = repo.commit('Initial commit\n')

    def test_graft_conflict_free_commit(self):
        # Create a new head.
        self.write_file('second.txt', '2')
        self.repo.add_file('second.txt')
        commit2 = self.repo.commit('Second commit\n')

        # Create another new head.
        self.repo.update(self.commit1)
        self.assertFalse(os.path.exists(self.get_path('second.txt')))
        self.write_file('third.txt', '3')
        self.repo.add_file('third.txt')
        commit3 = self.repo.commit('Third commit\n')

        # Perform graft.
        self.hg('graft', commit2)

        # Verify we end up with the expected stack of commits.
        self.assert_status_empty()
        commits = self.repo.log()
        self.assertEqual(3, len(commits))
        self.assertEqual([self.commit1, commit3], commits[:2])
        self.assertTrue(os.path.exists(self.get_path('second.txt')))

    def test_graft_commit_with_conflict(self):
        # Create a new head.
        self.write_file('first.txt', '2')
        commit2 = self.repo.commit('Updated first.txt.\n')

        # Create another new head that modifies first.txt in a different way.
        self.repo.update(self.commit1)
        self.write_file('first.txt', '3')
        commit3 = self.repo.commit('Alternative update to first.txt.\n')

        # Attempt graft.
        with self.assertRaises(hgrepo.HgError) as context:
            self.hg('graft', commit2)
        self.assertIn(
            (
                "warning: conflicts while merging first.txt!"
                " (edit, then use 'hg resolve --mark')\n"
                "  abort: unresolved conflicts, can't continue\n"
            ), str(context.exception)
        )

        # Resolve conflict with something completely different.
        self.write_file('first.txt', '23')
        self.hg('resolve', '--mark', self.get_path('first.txt'))
        self.hg('graft', '--continue')

        # Verify we end up with the expected stack of commits.
        self.assert_status_empty()
        commits = self.repo.log()
        self.assertEqual(3, len(commits))
        self.assertEqual([self.commit1, commit3], commits[:2])

    def test_graft_that_removes_a_file(self):
        # Create a new head that adds second.txt and removes first.txt.
        self.write_file('second.txt', '2')
        self.repo.add_file('second.txt')
        self.hg('rm', 'first.txt')
        commit2 = self.repo.commit('Add second.txt and remove first.txt.')

        # Create a separate head that adds third.txt.
        self.repo.update(self.commit1)
        self.write_file('third.txt', '3')
        self.repo.add_file('third.txt')
        commit3 = self.repo.commit('Add third.txt.')

        # Perform the graft and verify we end up in the right state.
        self.hg('graft', commit2)
        self.assert_status_empty()
        commits = self.repo.log()
        self.assertEqual(3, len(commits))
        self.assertEqual([self.commit1, commit3], commits[:2])
        self.assertFalse(os.path.exists(self.get_path('first.txt')))
        self.assertTrue(os.path.exists(self.get_path('second.txt')))
        self.assertTrue(os.path.exists(self.get_path('third.txt')))