1 files changed, 220 insertions, 0 deletions
diff --git a/tests/error_handler_test.py b/tests/error_handler_test.py
new file mode 100644
index 0000000..a79d9c1
--- /dev/null
+++ b/tests/error_handler_test.py
@@ -0,0 +1,220 @@
+from __future__ import annotations
+
+import os.path
+import stat
+import sys
+from unittest import mock
+
+import pytest
+import re_assert
+
+from pre_commit import error_handler
+from pre_commit.errors import FatalError
+from pre_commit.store import Store
+from pre_commit.util import CalledProcessError
+from testing.util import cmd_output_mocked_pre_commit_home
+from testing.util import xfailif_windows
+
+
+@pytest.fixture
+def mocked_log_and_exit():
+    with mock.patch.object(error_handler, '_log_and_exit') as log_and_exit:
+        yield log_and_exit
+
+
+def test_error_handler_no_exception(mocked_log_and_exit):
+    with error_handler.error_handler():
+        pass
+    assert mocked_log_and_exit.call_count == 0
+
+
+def test_error_handler_fatal_error(mocked_log_and_exit):
+    exc = FatalError('just a test')
+    with error_handler.error_handler():
+        raise exc
+
+    mocked_log_and_exit.assert_called_once_with(
+        'An error has occurred',
+        1,
+        exc,
+        # Tested below
+        mock.ANY,
+    )
+
+    pattern = re_assert.Matches(
+        r'Traceback \(most recent call last\):\n'
+        r'  File ".+pre_commit.error_handler.py", line \d+, in error_handler\n'
+        r'    yield\n'
+        r'(    \^\^\^\^\^\n)?'
+        r'  File ".+tests.error_handler_test.py", line \d+, '
+        r'in test_error_handler_fatal_error\n'
+        r'    raise exc\n'
+        r'(    \^\^\^\^\^\^\^\^\^\n)?'
+        r'(pre_commit\.errors\.)?FatalError: just a test\n',
+    )
+    pattern.assert_matches(mocked_log_and_exit.call_args[0][3])
+
+
+def test_error_handler_uncaught_error(mocked_log_and_exit):
+    exc = ValueError('another test')
+    with error_handler.error_handler():
+        raise exc
+
+    mocked_log_and_exit.assert_called_once_with(
+        'An unexpected error has occurred',
+        3,
+        exc,
+        # Tested below
+        mock.ANY,
+    )
+    pattern = re_assert.Matches(
+        r'Traceback \(most recent call last\):\n'
+        r'  File ".+pre_commit.error_handler.py", line \d+, in error_handler\n'
+        r'    yield\n'
+        r'(    \^\^\^\^\^\n)?'
+        r'  File ".+tests.error_handler_test.py", line \d+, '
+        r'in test_error_handler_uncaught_error\n'
+        r'    raise exc\n'
+        r'(    \^\^\^\^\^\^\^\^\^\n)?'
+        r'ValueError: another test\n',
+    )
+    pattern.assert_matches(mocked_log_and_exit.call_args[0][3])
+
+
+def test_error_handler_keyboardinterrupt(mocked_log_and_exit):
+    exc = KeyboardInterrupt()
+    with error_handler.error_handler():
+        raise exc
+
+    mocked_log_and_exit.assert_called_once_with(
+        'Interrupted (^C)',
+        130,
+        exc,
+        # Tested below
+        mock.ANY,
+    )
+    pattern = re_assert.Matches(
+        r'Traceback \(most recent call last\):\n'
+        r'  File ".+pre_commit.error_handler.py", line \d+, in error_handler\n'
+        r'    yield\n'
+        r'(    \^\^\^\^\^\n)?'
+        r'  File ".+tests.error_handler_test.py", line \d+, '
+        r'in test_error_handler_keyboardinterrupt\n'
+        r'    raise exc\n'
+        r'(    \^\^\^\^\^\^\^\^\^\n)?'
+        r'KeyboardInterrupt\n',
+    )
+    pattern.assert_matches(mocked_log_and_exit.call_args[0][3])
+
+
+def test_log_and_exit(cap_out, mock_store_dir):
+    tb = (
+        'Traceback (most recent call last):\n'
+        '  File "<stdin>", line 2, in <module>\n'
+        'pre_commit.errors.FatalError: hai\n'
+    )
+
+    with pytest.raises(SystemExit) as excinfo:
+        error_handler._log_and_exit('msg', 1, FatalError('hai'), tb)
+    assert excinfo.value.code == 1
+
+    printed = cap_out.get()
+    log_file = os.path.join(mock_store_dir, 'pre-commit.log')
+    assert printed == f'msg: FatalError: hai\nCheck the log at {log_file}\n'
+
+    assert os.path.exists(log_file)
+    with open(log_file) as f:
+        logged = f.read()
+        pattern = re_assert.Matches(
+            r'^### version information\n'
+            r'\n'
+            r'```\n'
+            r'pre-commit version: \d+\.\d+\.\d+\n'
+            r'git --version: git version .+\n'
+            r'sys.version:\n'
+            r'(    .*\n)*'
+            r'sys.executable: .*\n'
+            r'os.name: .*\n'
+            r'sys.platform: .*\n'
+            r'```\n'
+            r'\n'
+            r'### error information\n'
+            r'\n'
+            r'```\n'
+            r'msg: FatalError: hai\n'
+            r'```\n'
+            r'\n'
+            r'```\n'
+            r'Traceback \(most recent call last\):\n'
+            r'  File "<stdin>", line 2, in <module>\n'
+            r'pre_commit\.errors\.FatalError: hai\n'
+            r'```\n',
+        )
+        pattern.assert_matches(logged)
+
+
+def test_error_handler_non_ascii_exception(mock_store_dir):
+    with pytest.raises(SystemExit):
+        with error_handler.error_handler():
+            raise ValueError('☃')
+
+
+def test_error_handler_non_utf8_exception(mock_store_dir):
+    with pytest.raises(SystemExit):
+        with error_handler.error_handler():
+            raise CalledProcessError(1, ('exe',), b'error: \xa0\xe1', b'')
+
+
+def test_error_handler_non_stringable_exception(mock_store_dir):
+    class C(Exception):
+        def __str__(self):
+            raise RuntimeError('not today!')
+
+    with pytest.raises(SystemExit):
+        with error_handler.error_handler():
+            raise C()
+
+
+def test_error_handler_no_tty(tempdir_factory):
+    pre_commit_home = tempdir_factory.get()
+    ret, out, _ = cmd_output_mocked_pre_commit_home(
+        sys.executable,
+        '-c',
+        'from pre_commit.error_handler import error_handler\n'
+        'with error_handler():\n'
+        '    raise ValueError("\\u2603")\n',
+        check=False,
+        tempdir_factory=tempdir_factory,
+        pre_commit_home=pre_commit_home,
+    )
+    assert ret == 3
+    log_file = os.path.join(pre_commit_home, 'pre-commit.log')
+    out_lines = out.splitlines()
+    assert out_lines[-2] == 'An unexpected error has occurred: ValueError: ☃'
+    assert out_lines[-1] == f'Check the log at {log_file}'
+
+
+@xfailif_windows  # pragma: win32 no cover
+def test_error_handler_read_only_filesystem(mock_store_dir, cap_out, capsys):
+    # a better scenario would be if even the Store crash would be handled
+    # but realistically we're only targetting systems where the Store has
+    # already been set up
+    Store()
+
+    write = (stat.S_IWGRP | stat.S_IWOTH | stat.S_IWUSR)
+    os.chmod(mock_store_dir, os.stat(mock_store_dir).st_mode & ~write)
+
+    with pytest.raises(SystemExit):
+        with error_handler.error_handler():
+            raise ValueError('ohai')
+
+    output = cap_out.get()
+    assert output.startswith(
+        'An unexpected error has occurred: ValueError: ohai\n'
+        'Failed to write to log at ',
+    )
+
+    # our cap_out mock is imperfect so the rest of the output goes to capsys
+    out, _ = capsys.readouterr()
+    # the things that normally go to the log file will end up here
+    assert '### version information' in out