Implement Store. pre-commit now installs files to ~/.pre-commit

tests/store_test.py

@@ -0,0 +1,134 @@
+import io
+import mock
+import os
+import os.path
+import pytest
+import shutil
+from plumbum import local
+
+from pre_commit import five
+from pre_commit.store import _get_default_directory
+from pre_commit.store import logger
+from pre_commit.store import Store
+from testing.util import get_head_sha
+
+
+def test_our_session_fixture_works():
+    """There's a session fixture which makes `Store` invariantly raise to
+    prevent writing to the home directory.
+    """
+    with pytest.raises(AssertionError):
+        Store()
+
+
+def test_get_default_directory_defaults_to_home():
+    # Not we use the module level one which is not mocked
+    ret = _get_default_directory()
+    assert ret == os.path.join(os.environ['HOME'], '.pre-commit')
+
+
+@pytest.yield_fixture
+def store(tmpdir_factory):
+    yield Store(os.path.join(tmpdir_factory.get(), '.pre-commit'))
+
+
+def test_store_require_created(store):
+    assert not os.path.exists(store.directory)
+    store.require_created()
+    # Should create the store directory
+    assert os.path.exists(store.directory)
+    # Should create a README file indicating what the directory is about
+    with io.open(os.path.join(store.directory, 'README'), 'r') as readme_file:
+        readme_contents = readme_file.read()
+        for text_line in (
+            'This directory is maintained by the pre-commit project.',
+            'Learn more: https://github.com/pre-commit/pre-commit',
+        ):
+            assert text_line in readme_contents
+
+
+def test_store_require_created_does_not_create_twice(store):
+    assert not os.path.exists(store.directory)
+    store.require_created()
+    # We intentionally delete the directory here so we can figure out if it
+    # calls it again.
+    shutil.rmtree(store.directory)
+    assert not os.path.exists(store.directory)
+    # Call require_created, this should not trigger a call to create
+    store.require_created()
+    assert not os.path.exists(store.directory)
+
+
+def test_does_not_recreate_if_directory_already_exists(store):
+    assert not os.path.exists(store.directory)
+    # We manually create the directory.
+    # Note: we're intentionally leaving out the README file.  This is so we can
+    # know that `Store` didn't call create
+    os.mkdir(store.directory)
+    # Call require_created, this should not call create
+    store.require_created()
+    assert not os.path.exists(os.path.join(store.directory, 'README'))
+
+
+@pytest.yield_fixture
+def log_info_mock():
+    with mock.patch.object(logger, 'info', autospec=True) as info_mock:
+        yield info_mock
+
+
+def test_clone(store, empty_git_dir, log_info_mock):
+    with local.cwd(empty_git_dir):
+        local['git']('commit', '--allow-empty', '-m', 'foo')
+        sha = get_head_sha(empty_git_dir)
+        local['git']('commit', '--allow-empty', '-m', 'bar')
+
+    ret = store.clone(empty_git_dir, sha)
+    # Should have printed some stuff
+    log_info_mock.assert_called_with('This may take a few minutes...')
+
+    # Should return a directory inside of the store
+    assert os.path.exists(ret)
+    assert ret.startswith(store.directory)
+    # Directory should start with `repo`
+    _, dirname = os.path.split(ret)
+    assert dirname.startswith('repo')
+    # Should be checked out to the sha we specified
+    assert get_head_sha(ret) == sha
+
+    # Assert that we made a symlink from the sha to the repo
+    sha_path = os.path.join(store.directory, sha)
+    assert os.path.exists(sha_path)
+    assert os.path.islink(sha_path)
+    assert os.readlink(sha_path) == ret
+
+
+def test_clone_cleans_up_on_checkout_failure(store):
+    try:
+        # This raises an exception because you can't clone something that
+        # doesn't exist!
+        store.clone('/i_dont_exist_lol', 'fake_sha')
+    except Exception as e:
+        assert '/i_dont_exist_lol' in five.text(e)
+
+    things_starting_with_repo = [
+        thing for thing in os.listdir(store.directory)
+        if thing.startswith('repo')
+    ]
+    assert things_starting_with_repo == []
+
+
+def test_has_cmd_runner_at_directory(store):
+    ret = store.cmd_runner
+    assert ret.prefix_dir == store.directory + os.sep
+
+
+def test_clone_when_repo_already_exists(store):
+    # Create a symlink and directory in the store simulating an already
+    # created repository.
+    store.require_created()
+    repo_dir_path = os.path.join(store.directory, 'repo_dir')
+    os.mkdir(repo_dir_path)
+    os.symlink(repo_dir_path, os.path.join(store.directory, 'fake_sha'))
+
+    ret = store.clone('url', 'fake_sha')
+    assert ret == repo_dir_path