flake8/tests/unit/test_base_formatter.py
Lukasz Langa 01c0c648e1 Only require Mock on Python 3.4 and older. Use the builtin one elsewhere.
Mock 2.0 is using pbr which is hostile to environments without network access.
It's not required on Python 3.5+ so I made it possible to use `unittest.mock`
on this version.

Updated tox.ini to reflect this. Tested with 2.7.11, 3.3.6, 3.4.5, and 3.5.2 on
macOS 10.12.1 with tox and pyenv.
2016-11-27 15:13:30 -08:00

166 lines
4.9 KiB
Python

"""Tests for the BaseFormatter object."""
import optparse
try:
import mock
except ImportError:
from unittest import mock
import pytest
from flake8 import style_guide
from flake8.formatting import base
def options(**kwargs):
"""Create an optparse.Values instance."""
kwargs.setdefault('output_file', None)
kwargs.setdefault('tee', False)
return optparse.Values(kwargs)
@pytest.mark.parametrize('filename', [None, 'out.txt'])
def test_start(filename):
"""Verify we open a new file in the start method."""
mock_open = mock.mock_open()
formatter = base.BaseFormatter(options(output_file=filename))
with mock.patch('flake8.formatting.base.open', mock_open):
formatter.start()
if filename is None:
assert mock_open.called is False
else:
mock_open.assert_called_once_with(filename, 'a')
def test_stop():
"""Verify we close open file objects."""
filemock = mock.Mock()
formatter = base.BaseFormatter(options())
formatter.output_fd = filemock
formatter.stop()
filemock.close.assert_called_once_with()
assert formatter.output_fd is None
def test_format_needs_to_be_implemented():
"""Ensure BaseFormatter#format raises a NotImplementedError."""
formatter = base.BaseFormatter(options())
with pytest.raises(NotImplementedError):
formatter.format('foo')
def test_show_source_returns_nothing_when_not_showing_source():
"""Ensure we return nothing when users want nothing."""
formatter = base.BaseFormatter(options(show_source=False))
assert formatter.show_source(
style_guide.Error('A000', 'file.py', 1, 1, 'error text', 'line')
) is ''
def test_show_source_returns_nothing_when_there_is_source():
"""Ensure we return nothing when there is no line."""
formatter = base.BaseFormatter(options(show_source=True))
assert formatter.show_source(
style_guide.Error('A000', 'file.py', 1, 1, 'error text', None)
) is ''
@pytest.mark.parametrize('line, column', [
('x=1\n', 2),
(' x=(1\n +2)\n', 5),
# TODO(sigmavirus24): Add more examples
])
def test_show_source_updates_physical_line_appropriately(line, column):
"""Ensure the error column is appropriately indicated."""
formatter = base.BaseFormatter(options(show_source=True))
error = style_guide.Error('A000', 'file.py', 1, column, 'error', line)
output = formatter.show_source(error)
_, pointer = output.rsplit('\n', 1)
assert pointer.count(' ') == (column - 1)
@pytest.mark.parametrize('tee', [False, True])
def test_write_uses_an_output_file(tee):
"""Verify that we use the output file when it's present."""
line = 'Something to write'
source = 'source'
filemock = mock.Mock()
formatter = base.BaseFormatter(options(tee=tee))
formatter.output_fd = filemock
with mock.patch('flake8.formatting.base.print') as print_func:
formatter.write(line, source)
if tee:
assert print_func.called
assert print_func.mock_calls == [
mock.call(line),
mock.call(source),
]
else:
assert not print_func.called
assert filemock.write.called is True
assert filemock.write.call_count == 2
assert filemock.write.mock_calls == [
mock.call(line + formatter.newline),
mock.call(source + formatter.newline),
]
@mock.patch('flake8.formatting.base.print')
def test_write_uses_print(print_function):
"""Verify that we use the print function without an output file."""
line = 'Something to write'
source = 'source'
formatter = base.BaseFormatter(options())
formatter.write(line, source)
assert print_function.called is True
assert print_function.call_count == 2
assert print_function.mock_calls == [
mock.call(line),
mock.call(source),
]
class AfterInitFormatter(base.BaseFormatter):
"""Subclass for testing after_init."""
def after_init(self):
"""Define method to verify operation."""
self.post_initialized = True
def test_after_init_is_always_called():
"""Verify after_init is called."""
formatter = AfterInitFormatter(options())
assert getattr(formatter, 'post_initialized') is True
class FormatFormatter(base.BaseFormatter):
"""Subclass for testing format."""
def format(self, error):
"""Define method to verify operation."""
return repr(error)
def test_handle_formats_the_error():
"""Verify that a formatter will call format from handle."""
formatter = FormatFormatter(options(show_source=False))
filemock = formatter.output_fd = mock.Mock()
error = style_guide.Error(
code='A001',
filename='example.py',
line_number=1,
column_number=1,
text='Fake error',
physical_line='a = 1',
)
formatter.handle(error)
filemock.write.assert_called_once_with(repr(error) + '\n')