Merge pull request #153 from pre-commit/error_handler

struys · struys · commit f3b5886c8a47 · 2014-08-13T11:34:39.000-07:00
Error handler
diff --git a/pre_commit/clientlib/validate_base.py b/pre_commit/clientlib/validate_base.py
@@ -6,10 +6,10 @@
 import jsonschema.exceptions
 import os.path
 import re
+import sys
 import yaml
 
 from pre_commit.jsonschema_extensions import apply_defaults
-from pre_commit.util import entry
 
 
 def is_regex_valid(regex):
@@ -64,8 +64,8 @@ def validate(filename, load_strategy=yaml.load):
 
 
 def get_run_function(filenames_help, validate_strategy, exception_cls):
-    @entry
-    def run(argv):
+    def run(argv=None):
+        argv = argv if argv is not None else sys.argv[1:]
         parser = argparse.ArgumentParser()
         parser.add_argument('filenames', nargs='*', help=filenames_help)
         args = parser.parse_args(argv)
diff --git a/pre_commit/clientlib/validate_config.py b/pre_commit/clientlib/validate_config.py
@@ -1,13 +1,12 @@
 from __future__ import unicode_literals
 
-import sys
-
 from pre_commit.clientlib.validate_base import get_run_function
 from pre_commit.clientlib.validate_base import get_validator
 from pre_commit.clientlib.validate_base import is_regex_valid
+from pre_commit.errors import FatalError
 
 
-class InvalidConfigError(ValueError):
+class InvalidConfigError(FatalError):
     pass
 
 
@@ -71,4 +70,4 @@ def validate_config_extra(config):
 
 
 if __name__ == '__main__':
-    sys.exit(run())
+    exit(run())
diff --git a/pre_commit/clientlib/validate_manifest.py b/pre_commit/clientlib/validate_manifest.py
@@ -1,7 +1,5 @@
 from __future__ import unicode_literals
 
-import sys
-
 from pre_commit.clientlib.validate_base import get_run_function
 from pre_commit.clientlib.validate_base import get_validator
 from pre_commit.clientlib.validate_base import is_regex_valid
@@ -74,4 +72,4 @@ def additional_manifest_check(obj):
 
 
 if __name__ == '__main__':
-    sys.exit(run())
+    exit(run())
diff --git a/pre_commit/error_handler.py b/pre_commit/error_handler.py
@@ -0,0 +1,42 @@
+from __future__ import absolute_import
+from __future__ import print_function
+from __future__ import unicode_literals
+
+import contextlib
+import io
+import os.path
+import traceback
+
+from pre_commit.errors import FatalError
+from pre_commit.store import Store
+
+
+# For testing purposes
+class PreCommitSystemExit(SystemExit):
+    pass
+
+
+def _log_and_exit(msg, exc, formatted, print_fn=print):
+    error_msg = '{0}: {1}: {2}'.format(msg, type(exc).__name__, exc)
+    print_fn(error_msg)
+    print_fn('Check the log at ~/.pre-commit/pre-commit.log')
+    store = Store()
+    store.require_created()
+    with io.open(os.path.join(store.directory, 'pre-commit.log'), 'w') as log:
+        log.write(error_msg + '\n')
+        log.write(formatted + '\n')
+    raise PreCommitSystemExit(1)
+
+
+@contextlib.contextmanager
+def error_handler():
+    try:
+        yield
+    except FatalError as e:
+        _log_and_exit('An error has occurred', e, traceback.format_exc())
+    except Exception as e:
+        _log_and_exit(
+            'An unexpected error has occurred',
+            e,
+            traceback.format_exc(),
+        )
diff --git a/pre_commit/errors.py b/pre_commit/errors.py
@@ -0,0 +1,6 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
+
+class FatalError(RuntimeError):
+    pass
diff --git a/pre_commit/five.py b/pre_commit/five.py
@@ -1,6 +1,5 @@
 from __future__ import unicode_literals
 
-"""five: six, redux"""
 # pylint:disable=invalid-name
 PY2 = str is bytes
 PY3 = str is not bytes
diff --git a/pre_commit/git.py b/pre_commit/git.py
@@ -7,21 +7,24 @@
 import re
 from plumbum import local
 
+from pre_commit.errors import FatalError
 from pre_commit.util import memoize_by_cwd
 
 
 logger = logging.getLogger('pre_commit')
 
 
-@memoize_by_cwd
 def get_root():
     path = os.getcwd()
     while len(path) > 1:
         if os.path.exists(os.path.join(path, '.git')):
             return path
         else:
             path = os.path.normpath(os.path.join(path, '../'))
-    raise AssertionError('called from outside of the gits')
+    raise FatalError(
+        'Called from outside of the gits. '
+        'Please cd to a git repository.'
+    )
 
 
 def is_in_merge_conflict():
diff --git a/pre_commit/jsonschema_extensions.py b/pre_commit/jsonschema_extensions.py
@@ -20,20 +20,20 @@ def new_properties(validator, properties, instance, schema):
 
 
 def default_values(properties, instance):
-    for property, subschema in properties.items():
+    for prop, subschema in properties.items():
         if 'default' in subschema:
             instance.setdefault(
-                property, copy.deepcopy(subschema['default']),
+                prop, copy.deepcopy(subschema['default']),
             )
 
 
 def remove_default_values(properties, instance):
-    for property, subschema in properties.items():
+    for prop, subschema in properties.items():
         if (
-            'default' in subschema and
-            instance.get(property) == subschema['default']
+                'default' in subschema and
+                instance.get(prop) == subschema['default']
         ):
-            del instance[property]
+            del instance[prop]
 
 
 _AddDefaultsValidator = extend_validator_cls(
diff --git a/pre_commit/main.py b/pre_commit/main.py
@@ -2,19 +2,20 @@
 
 import argparse
 import pkg_resources
+import sys
 
 from pre_commit import color
 from pre_commit.commands.autoupdate import autoupdate
 from pre_commit.commands.clean import clean
 from pre_commit.commands.install_uninstall import install
 from pre_commit.commands.install_uninstall import uninstall
 from pre_commit.commands.run import run
+from pre_commit.error_handler import error_handler
 from pre_commit.runner import Runner
-from pre_commit.util import entry
 
 
-@entry
-def main(argv):
+def main(argv=None):
+    argv = argv if argv is not None else sys.argv[1:]
     parser = argparse.ArgumentParser()
 
     # http://stackoverflow.com/a/8521644/812183
@@ -83,29 +84,30 @@ def main(argv):
         else:
             parser.parse_args(['--help'])
 
-    runner = Runner.create()
+    with error_handler():
+        runner = Runner.create()
+
+        if args.command == 'install':
+            return install(
+                runner, overwrite=args.overwrite, hooks=args.install_hooks,
+            )
+        elif args.command == 'uninstall':
+            return uninstall(runner)
+        elif args.command == 'clean':
+            return clean(runner)
+        elif args.command == 'autoupdate':
+            return autoupdate(runner)
+        elif args.command == 'run':
+            return run(runner, args)
+        else:
+            raise NotImplementedError(
+                'Command {0} not implemented.'.format(args.command)
+            )
 
-    if args.command == 'install':
-        return install(
-            runner, overwrite=args.overwrite, hooks=args.install_hooks,
-        )
-    elif args.command == 'uninstall':
-        return uninstall(runner)
-    elif args.command == 'clean':
-        return clean(runner)
-    elif args.command == 'autoupdate':
-        return autoupdate(runner)
-    elif args.command == 'run':
-        return run(runner, args)
-    else:
-        raise NotImplementedError(
-            'Command {0} not implemented.'.format(args.command)
+        raise AssertionError(
+            'Command {0} failed to exit with a returncode'.format(args.command)
         )
 
-    raise AssertionError(
-        'Command {0} failed to exit with a returncode'.format(args.command)
-    )
-
 
 if __name__ == '__main__':
     exit(main())
diff --git a/pre_commit/output.py b/pre_commit/output.py
@@ -16,13 +16,13 @@
 
 
 def get_hook_message(
-    start,
-    postfix='',
-    end_msg=None,
-    end_len=0,
-    end_color=None,
-    use_color=None,
-    cols=COLS,
+        start,
+        postfix='',
+        end_msg=None,
+        end_len=0,
+        end_color=None,
+        use_color=None,
+        cols=COLS,
 ):
     """Prints a message for running a hook.
 
diff --git a/pre_commit/util.py b/pre_commit/util.py
@@ -7,7 +7,6 @@
 import os.path
 import pkg_resources
 import shutil
-import sys
 import tarfile
 import tempfile
 
@@ -29,19 +28,6 @@ def wrapper(*args):
     return wrapper
 
 
-def entry(func):
-    """Allows a function that has `argv` as an argument to be used as a
-    commandline entry.  This will make the function callable using either
-    explicitly passed argv or defaulting to sys.argv[1:]
-    """
-    @functools.wraps(func)
-    def wrapper(argv=None):
-        if argv is None:
-            argv = sys.argv[1:]
-        return func(argv)
-    return wrapper
-
-
 @contextlib.contextmanager
 def clean_path_on_failure(path):
     """Cleans up the directory on an exceptional failure."""
diff --git a/pylintrc b/pylintrc
@@ -1,5 +1,5 @@
 [MESSAGES CONTROL]
-disable=missing-docstring,abstract-method,redefined-builtin,useless-else-on-loop,redefined-outer-name,invalid-name
+disable=locally-disabled,fixme,missing-docstring,abstract-method,useless-else-on-loop,invalid-name
 
 [REPORTS]
 output-format=colorized
diff --git a/tests/error_handler_test.py b/tests/error_handler_test.py
@@ -0,0 +1,93 @@
+from __future__ import absolute_import
+from __future__ import unicode_literals
+
+import io
+import os.path
+import mock
+import pytest
+import re
+
+from pre_commit import error_handler
+from pre_commit.errors import FatalError
+
+
+@pytest.yield_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',
+        exc,
+        # Tested below
+        mock.ANY,
+    )
+
+    assert re.match(
+        'Traceback \(most recent call last\):\n'
+        '  File ".+/pre_commit/error_handler.py", line \d+, in error_handler\n'
+        '    yield\n'
+        '  File ".+/tests/error_handler_test.py", line \d+, '
+        'in test_error_handler_fatal_error\n'
+        '    raise exc\n'
+        '(pre_commit\.errors\.)?FatalError: just a test\n',
+        mocked_log_and_exit.call_args[0][2],
+    )
+
+
+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',
+        exc,
+        # Tested below
+        mock.ANY,
+    )
+    assert re.match(
+        'Traceback \(most recent call last\):\n'
+        '  File ".+/pre_commit/error_handler.py", line \d+, in error_handler\n'
+        '    yield\n'
+        '  File ".+/tests/error_handler_test.py", line \d+, '
+        'in test_error_handler_uncaught_error\n'
+        '    raise exc\n'
+        'ValueError: another test\n',
+        mocked_log_and_exit.call_args[0][2],
+    )
+
+
+def test_log_and_exit(mock_out_store_directory):
+    mocked_print = mock.Mock()
+    with pytest.raises(error_handler.PreCommitSystemExit):
+        error_handler._log_and_exit(
+            'msg', FatalError('hai'), "I'm a stacktrace",
+            print_fn=mocked_print,
+        )
+
+    printed = '\n'.join(call[0][0] for call in mocked_print.call_args_list)
+    assert printed == (
+        'msg: FatalError: hai\n'
+        'Check the log at ~/.pre-commit/pre-commit.log'
+    )
+
+    log_file = os.path.join(mock_out_store_directory, 'pre-commit.log')
+    assert os.path.exists(log_file)
+    contents = io.open(log_file).read()
+    assert contents == (
+        'msg: FatalError: hai\n'
+        "I'm a stacktrace\n"
+    )
diff --git a/tests/git_test.py b/tests/git_test.py
diff --git a/tests/util_test.py b/tests/util_test.py
