third_party.pylibs.pylint.src/pylint/testutils/lint_module_test.py
2022-04-14 10:13:26 +02:00

269 lines
10 KiB
Python

# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
# For details: https://github.com/PyCQA/pylint/blob/main/LICENSE
# Copyright (c) https://github.com/PyCQA/pylint/blob/main/CONTRIBUTORS.txt
from __future__ import annotations
import csv
import operator
import platform
import sys
from collections import Counter
from io import StringIO
from pathlib import Path
from typing import Counter as CounterType
from typing import TextIO, Tuple
import pytest
from _pytest.config import Config
from pylint import checkers
from pylint.config.config_initialization import _config_initialization
from pylint.lint import PyLinter
from pylint.message.message import Message
from pylint.testutils.constants import _EXPECTED_RE, _OPERATORS, UPDATE_OPTION
from pylint.testutils.functional.test_file import ( # need to import from functional.test_file to avoid cyclic import
FunctionalTestFile,
NoFileError,
parse_python_version,
)
from pylint.testutils.output_line import OutputLine
from pylint.testutils.reporter_for_tests import FunctionalTestReporter
MessageCounter = CounterType[Tuple[int, str]]
PYLINTRC = Path(__file__).parent / "testing_pylintrc"
class LintModuleTest:
maxDiff = None
def __init__(
self, test_file: FunctionalTestFile, config: Config | None = None
) -> None:
_test_reporter = FunctionalTestReporter()
self._linter = PyLinter()
self._linter.namespace.persistent = 0
checkers.initialize(self._linter)
# See if test has its own .rc file, if so we use that one
rc_file: Path | str = PYLINTRC
try:
rc_file = test_file.option_file
self._linter.disable("suppressed-message")
self._linter.disable("locally-disabled")
self._linter.disable("useless-suppression")
except NoFileError:
pass
try:
args = [test_file.source]
except NoFileError:
# If we're still raising NoFileError the actual source file doesn't exist
args = [""]
_config_initialization(
self._linter, args_list=args, config_file=rc_file, reporter=_test_reporter
)
self._test_file = test_file
self._config = config
self._check_end_position = (
sys.version_info >= self._test_file.options["min_pyver_end_position"]
)
def setUp(self) -> None:
if self._should_be_skipped_due_to_version():
pytest.skip(
f"Test cannot run with Python {sys.version.split(' ', maxsplit=1)[0]}."
)
missing = []
for requirement in self._test_file.options["requires"]:
try:
__import__(requirement)
except ImportError:
missing.append(requirement)
if missing:
pytest.skip(f"Requires {','.join(missing)} to be present.")
except_implementations = self._test_file.options["except_implementations"]
if except_implementations:
if platform.python_implementation() in except_implementations:
msg = "Test cannot run with Python implementation %r"
pytest.skip(msg % platform.python_implementation())
excluded_platforms = self._test_file.options["exclude_platforms"]
if excluded_platforms:
if sys.platform.lower() in excluded_platforms:
pytest.skip(f"Test cannot run on platform {sys.platform!r}")
def runTest(self) -> None:
self._runTest()
def _should_be_skipped_due_to_version(self) -> bool:
return (
sys.version_info < self._test_file.options["min_pyver"]
or sys.version_info > self._test_file.options["max_pyver"]
)
def __str__(self) -> str:
return f"{self._test_file.base} ({self.__class__.__module__}.{self.__class__.__name__})"
@staticmethod
def get_expected_messages(stream: TextIO) -> MessageCounter:
"""Parses a file and get expected messages.
:param stream: File-like input stream.
:type stream: enumerable
:returns: A dict mapping line,msg-symbol tuples to the count on this line.
:rtype: dict
"""
messages: MessageCounter = Counter()
for i, line in enumerate(stream):
match = _EXPECTED_RE.search(line)
if match is None:
continue
line = match.group("line")
if line is None:
lineno = i + 1
elif line.startswith("+") or line.startswith("-"):
lineno = i + 1 + int(line)
else:
lineno = int(line)
version = match.group("version")
op = match.group("op")
if version:
required = parse_python_version(version)
if not _OPERATORS[op](sys.version_info, required):
continue
for msg_id in match.group("msgs").split(","):
messages[lineno, msg_id.strip()] += 1
return messages
@staticmethod
def multiset_difference(
expected_entries: MessageCounter,
actual_entries: MessageCounter,
) -> tuple[MessageCounter, dict[tuple[int, str], int]]:
"""Takes two multisets and compares them.
A multiset is a dict with the cardinality of the key as the value.
"""
missing = expected_entries.copy()
missing.subtract(actual_entries)
unexpected = {}
for key, value in list(missing.items()):
if value <= 0:
missing.pop(key)
if value < 0:
unexpected[key] = -value
return missing, unexpected
def _open_expected_file(self) -> TextIO:
try:
return open(self._test_file.expected_output, encoding="utf-8")
except FileNotFoundError:
return StringIO("")
def _open_source_file(self) -> TextIO:
if self._test_file.base == "invalid_encoded_data":
return open(self._test_file.source, encoding="utf-8")
if "latin1" in self._test_file.base:
return open(self._test_file.source, encoding="latin1")
return open(self._test_file.source, encoding="utf8")
def _get_expected(self) -> tuple[MessageCounter, list[OutputLine]]:
with self._open_source_file() as f:
expected_msgs = self.get_expected_messages(f)
if not expected_msgs:
expected_msgs = Counter()
with self._open_expected_file() as f:
expected_output_lines = [
OutputLine.from_csv(row, self._check_end_position)
for row in csv.reader(f, "test")
]
return expected_msgs, expected_output_lines
def _get_actual(self) -> tuple[MessageCounter, list[OutputLine]]:
messages: list[Message] = self._linter.reporter.messages
messages.sort(key=lambda m: (m.line, m.symbol, m.msg))
received_msgs: MessageCounter = Counter()
received_output_lines = []
for msg in messages:
assert (
msg.symbol != "fatal"
), f"Pylint analysis failed because of '{msg.msg}'"
received_msgs[msg.line, msg.symbol] += 1
received_output_lines.append(
OutputLine.from_msg(msg, self._check_end_position)
)
return received_msgs, received_output_lines
def _runTest(self) -> None:
__tracebackhide__ = True # pylint: disable=unused-variable
modules_to_check = [self._test_file.source]
self._linter.check(modules_to_check)
expected_messages, expected_output = self._get_expected()
actual_messages, actual_output = self._get_actual()
assert (
expected_messages == actual_messages
), self.error_msg_for_unequal_messages(
actual_messages, expected_messages, actual_output
)
self._check_output_text(expected_messages, expected_output, actual_output)
def error_msg_for_unequal_messages(
self,
actual_messages: MessageCounter,
expected_messages: MessageCounter,
actual_output: list[OutputLine],
) -> str:
msg = [f'Wrong results for file "{self._test_file.base}":']
missing, unexpected = self.multiset_difference(
expected_messages, actual_messages
)
if missing:
msg.append("\nExpected in testdata:")
msg.extend(f" {msg[0]:3}: {msg[1]}" for msg in sorted(missing))
if unexpected:
msg.append("\nUnexpected in testdata:")
msg.extend(f" {msg[0]:3}: {msg[1]}" for msg in sorted(unexpected))
error_msg = "\n".join(msg)
if self._config and self._config.getoption("verbose") > 0:
error_msg += "\n\nActual pylint output for this file:\n"
error_msg += "\n".join(str(o) for o in actual_output)
return error_msg
def error_msg_for_unequal_output(
self,
expected_lines: list[OutputLine],
received_lines: list[OutputLine],
) -> str:
missing = set(expected_lines) - set(received_lines)
unexpected = set(received_lines) - set(expected_lines)
error_msg = (
f"Wrong output for '{self._test_file.base}.txt':\n"
"You can update the expected output automatically with: '"
f"python tests/test_functional.py {UPDATE_OPTION} -k "
f'"test_functional[{self._test_file.base}]"\'\n\n'
)
sort_by_line_number = operator.attrgetter("lineno")
if missing:
error_msg += "\n- Missing lines:\n"
for line in sorted(missing, key=sort_by_line_number):
error_msg += f"{line}\n"
if unexpected:
error_msg += "\n- Unexpected lines:\n"
for line in sorted(unexpected, key=sort_by_line_number):
error_msg += f"{line}\n"
return error_msg
def _check_output_text(
self,
_: MessageCounter,
expected_output: list[OutputLine],
actual_output: list[OutputLine],
) -> None:
"""This is a function because we want to be able to update the text in LintModuleOutputUpdate."""
assert expected_output == actual_output, self.error_msg_for_unequal_output(
expected_output, actual_output
)