Merge pull request #343 from pre-commit/testing_helpers

Make a helper for running pre-commit as a subprocess under test

testing/util.py

@@ -49,6 +49,15 @@ def is_valid_according_to_schema(obj, schema):
         return False
 
 
+def cmd_output_mocked_pre_commit_home(*args, **kwargs):
+    # keyword-only argument
+    tempdir_factory = kwargs.pop('tempdir_factory')
+    pre_commit_home = kwargs.pop('pre_commit_home', tempdir_factory.get())
+    # Don't want to write to the home directory
+    env = dict(kwargs.pop('env', os.environ), PRE_COMMIT_HOME=pre_commit_home)
+    return cmd_output(*args, env=env, **kwargs)
+
+
 skipif_slowtests_false = pytest.mark.skipif(
     os.environ.get('slowtests') == 'false',
     reason='slowtests=false',

tests/commands/install_uninstall_test.py

@@ -25,6 +25,7 @@ from pre_commit.util import mkdirp
 from pre_commit.util import resource_filename
 from testing.fixtures import git_dir
 from testing.fixtures import make_consuming_repo
+from testing.util import cmd_output_mocked_pre_commit_home
 from testing.util import xfailif_no_symlink
 
 
@@ -121,23 +122,16 @@ def test_uninstall(tempdir_factory):
     assert not os.path.exists(runner.pre_commit_path)
 
 
-def _get_commit_output(
-        tempdir_factory,
-        touch_file='foo',
-        home=None,
-        env_base=os.environ,
-):
+def _get_commit_output(tempdir_factory, touch_file='foo', **kwargs):
     cmd_output('touch', touch_file)
     cmd_output('git', 'add', touch_file)
-    # Don't want to write to home directory
-    home = home or tempdir_factory.get()
-    env = dict(env_base, PRE_COMMIT_HOME=home)
-    return cmd_output(
+    return cmd_output_mocked_pre_commit_home(
         'git', 'commit', '-am', 'Commit!', '--allow-empty',
         # git commit puts pre-commit to stderr
         stderr=subprocess.STDOUT,
-        env=env,
         retcode=None,
+        tempdir_factory=tempdir_factory,
+        **kwargs
     )[:2]
 
 
@@ -458,7 +452,7 @@ def test_installs_hooks_with_hooks_True(
     with cwd(path):
         install(Runner(path), hooks=True)
         ret, output = _get_commit_output(
-            tempdir_factory, home=mock_out_store_directory,
+            tempdir_factory, pre_commit_home=mock_out_store_directory,
         )
 
         assert ret == 0
@@ -473,7 +467,7 @@ def test_installed_from_venv(tempdir_factory):
         # Should still pick up the python from when we installed
         ret, output = _get_commit_output(
             tempdir_factory,
-            env_base={
+            env={
                 'HOME': os.path.expanduser('~'),
                 'PATH': _path_without_us(),
                 'TERM': os.environ.get('TERM', ''),
@@ -486,14 +480,11 @@ def test_installed_from_venv(tempdir_factory):
 
 
 def _get_push_output(tempdir_factory):
-    # Don't want to write to home directory
-    home = tempdir_factory.get()
-    env = dict(os.environ, PRE_COMMIT_HOME=home)
-    return cmd_output(
+    return cmd_output_mocked_pre_commit_home(
         'git', 'push', 'origin', 'HEAD:new_branch',
-        # git commit puts pre-commit to stderr
+        # git push puts pre-commit to stderr
         stderr=subprocess.STDOUT,
-        env=env,
+        tempdir_factory=tempdir_factory,
         retcode=None,
     )[:2]
 

tests/commands/run_test.py

@@ -26,6 +26,7 @@ from testing.auto_namedtuple import auto_namedtuple
 from testing.fixtures import add_config_to_repo
 from testing.fixtures import make_consuming_repo
 from testing.fixtures import modify_config
+from testing.util import cmd_output_mocked_pre_commit_home
 
 
 @pytest.yield_fixture
@@ -336,11 +337,9 @@ def test_non_ascii_hook_id(
 ):
     with cwd(repo_with_passing_hook):
         install(Runner(repo_with_passing_hook))
-        # Don't want to write to home directory
-        env = dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get())
-        _, stdout, _ = cmd_output(
+        _, stdout, _ = cmd_output_mocked_pre_commit_home(
             sys.executable, '-m', 'pre_commit.main', 'run', '☃',
-            env=env, retcode=None,
+            retcode=None, tempdir_factory=tempdir_factory,
         )
         assert 'UnicodeDecodeError' not in stdout
         # Doesn't actually happen, but a reasonable assertion
@@ -357,15 +356,13 @@ def test_stdout_write_bug_py26(
 
         install(Runner(repo_with_failing_hook))
 
-        # Don't want to write to home directory
-        env = dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get())
         # Have to use subprocess because pytest monkeypatches sys.stdout
-        _, stdout, _ = cmd_output(
+        _, stdout, _ = cmd_output_mocked_pre_commit_home(
             'git', 'commit', '-m', 'Commit!',
             # git commit puts pre-commit to stderr
             stderr=subprocess.STDOUT,
-            env=env,
             retcode=None,
+            tempdir_factory=tempdir_factory,
         )
         assert 'UnicodeEncodeError' not in stdout
         # Doesn't actually happen, but a reasonable assertion
@@ -377,15 +374,13 @@ def test_hook_install_failure(mock_out_store_directory, tempdir_factory):
     with cwd(git_path):
         install(Runner(git_path))
 
-        # Don't want to write to home directory
-        env = dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get())
-        _, stdout, _ = cmd_output(
+        _, stdout, _ = cmd_output_mocked_pre_commit_home(
             'git', 'commit', '-m', 'Commit!',
             # git commit puts pre-commit to stderr
             stderr=subprocess.STDOUT,
-            env=env,
             retcode=None,
             encoding=None,
+            tempdir_factory=tempdir_factory,
         )
         assert b'UnicodeDecodeError' not in stdout
         # Doesn't actually happen, but a reasonable assertion
@@ -424,13 +419,11 @@ def test_lots_of_files(mock_out_store_directory, tempdir_factory):
         cmd_output('bash', '-c', 'git add .')
         install(Runner(git_path))
 
-        # Don't want to write to home directory
-        env = dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get())
-        cmd_output(
+        cmd_output_mocked_pre_commit_home(
             'git', 'commit', '-m', 'Commit!',
             # git commit puts pre-commit to stderr
             stderr=subprocess.STDOUT,
-            env=env,
+            tempdir_factory=tempdir_factory,
         )
 
 
@@ -609,13 +602,11 @@ def test_files_running_subdir(
         cmd_output('git', 'add', 'subdir/foo.py')
 
         with cwd('subdir'):
-            # Don't want to write to home directory
-            env = dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get())
             # Use subprocess to demonstrate behaviour in main
-            _, stdout, _ = cmd_output(
+            _, stdout, _ = cmd_output_mocked_pre_commit_home(
                 sys.executable, '-m', 'pre_commit.main', 'run', '-v',
                 # Files relative to where we are (#339)
                 '--files', 'foo.py',
-                env=env,
+                tempdir_factory=tempdir_factory,
             )
         assert 'subdir/foo.py'.replace('/', os.sep) in stdout

tests/error_handler_test.py

@@ -13,7 +13,7 @@ import pytest
 from pre_commit import error_handler
 from pre_commit import five
 from pre_commit.errors import FatalError
-from pre_commit.util import cmd_output
+from testing.util import cmd_output_mocked_pre_commit_home
 
 
 @pytest.yield_fixture
@@ -107,14 +107,14 @@ def test_error_handler_non_ascii_exception(mock_out_store_directory):
 
 
 def test_error_handler_no_tty(tempdir_factory):
-    output = cmd_output(
+    output = cmd_output_mocked_pre_commit_home(
         sys.executable, '-c',
         'from __future__ import unicode_literals\n'
         'from pre_commit.error_handler import error_handler\n'
         'with error_handler():\n'
         '    raise ValueError("\\u2603")\n',
-        env=dict(os.environ, PRE_COMMIT_HOME=tempdir_factory.get()),
         retcode=1,
+        tempdir_factory=tempdir_factory,
     )
     assert output[1].replace('\r', '') == (
         'An unexpected error has occurred: ValueError: ☃\n'