spec.py

#!/usr/bin/env python

import os
import subprocess
import unittest


class AddIssueIdHookTest(unittest.TestCase):

    def setUp(self):
        self.execute('git init tmp_repo', 'cp add_issue_id.py tmp_repo/.git/hooks/commit-msg')
        os.chdir('tmp_repo')

    def test_prepends_issue_id_from_branch_name_to_commit_message(self):
        # given
        self.on_branch('some_EXAMPLE-1337_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file.')

        # then
        self.assert_last_commit_message_is('Added some file. EXAMPLE-1337')

    def test_prepends_first_matching_issue_id_to_commit_message_if_multiple_ids_in_branch_name_exist(self):
        # given
        self.on_branch('some_EXAMPLE-1337_feature_EXAMPLE-99')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file.')

        # then
        self.assert_last_commit_message_is('Added some file. EXAMPLE-1337')

    def test_prepends_issue_id_to_commit_message_when_message_contains_a_different_issue_id(self):
        # given
        self.on_branch('EXAMPLE-1337_some_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file fixing problems in EXAMPLE-99.')

        # then
        self.assert_last_commit_message_is('Added some file fixing problems in EXAMPLE-99. EXAMPLE-1337')

    def test_doesnt_modify_commit_message_if_issue_id_not_in_branch_name(self):
        # given
        self.on_branch('some_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file.')

        # then
        self.assert_last_commit_message_is('Added some file.')

    def test_doesnt_modify_commit_message_if_it_already_contains_this_issue_id(self):
        # given
        self.on_branch('EXAMPLE-1337_some_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file. EXAMPLE-1337')

        # then
        self.assert_last_commit_message_is('Added some file. EXAMPLE-1337')

    def test_doesnt_modify_commit_message_if_in_detached_HEAD_state(self):
        # given
        self.with_initial_commit()
        self.in_detached_head_state()
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('Added some file.')

        # then
        self.assert_last_commit_message_is('Added some file.')

    def test_supports_aborting_a_commit_by_providing_an_empty_message(self):
        # given
        self.on_branch('EXAMPLE-1337_some_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_with_message('')

        # then
        self.assert_no_commits_made()

    def test_supports_aborting_a_commit_by_exiting_from_editor_without_making_changes(self):
        # given
        self.on_branch('EXAMPLE-1337_some_feature')
        self.with_changes_to_be_committed()

        # when
        self.commit_exiting_from_editor_without_changes()

        # then
        self.assert_no_commits_made()

    def on_branch(self, branch_name):
        self.execute('git checkout -b {}'.format(branch_name))

    def with_changes_to_be_committed(self):
        self.execute('echo . >> some_file', 'git add some_file')

    def with_initial_commit(self):
        self.on_branch('EXAMPLE-1337_some_feature')
        self.with_changes_to_be_committed()
        self.commit_with_message('Some commit')

    def in_detached_head_state(self):
        self.execute('git checkout --detach')

    def commit_with_message(self, message):
        self.execute('git commit -m "{}"'.format(message))

    def commit_exiting_from_editor_without_changes(self):
        self.execute('git config core.editor vim')
        self.execute('echo ":q" | git commit -a')
        self.execute('git config --unset core.editor')

    def execute(self, *commands):
        try:
            return subprocess.check_output('; '.join(commands), shell=True).decode()
        except subprocess.CalledProcessError as e:
            print(e)

    def assert_last_commit_message_is(self, expected):
        self.assertEqual(self.execute('git log -1 --pretty=format:"%s"'), expected)

    def assert_no_commits_made(self):
        self.assertEqual(self.execute('git branch'), '')

    def tearDown(self):
        os.chdir('..')
        self.execute('rm -rf tmp_repo/')


if __name__ == '__main__':
    unittest.main()