Source code for prospector.tools.pylint
import os
import re
import sys
from collections import defaultdict
from pathlib import Path
from typing import List
from pylint.config import find_pylintrc
from pylint.exceptions import UnknownMessageError
from pylint.lint.run import _cpu_count
from prospector.finder import FileFinder
from prospector.message import Location, Message
from prospector.tools.base import ToolBase
from prospector.tools.pylint.collector import Collector
from prospector.tools.pylint.linter import ProspectorLinter
_UNUSED_WILDCARD_IMPORT_RE = re.compile(r"^Unused import(\(s\))? (.*) from wildcard import")
def _is_in_dir(subpath: Path, path: Path) -> bool:
return subpath.parent == path
[docs]
class PylintTool(ToolBase):
# There are several methods on this class which could technically
# be functions (they don't use the 'self' argument) but that would
# make this module/class a bit ugly.
def __init__(self):
self._args = None
self._collector = self._linter = None
self._orig_sys_path = []
def _prospector_configure(self, prospector_config, linter: ProspectorLinter):
errors = []
if "django" in prospector_config.libraries:
linter.load_plugin_modules(["pylint_django"])
if "celery" in prospector_config.libraries:
linter.load_plugin_modules(["pylint_celery"])
if "flask" in prospector_config.libraries:
linter.load_plugin_modules(["pylint_flask"])
profile_path = os.path.join(prospector_config.workdir, prospector_config.profile.name)
for plugin in prospector_config.profile.pylint.get("load-plugins", []):
try:
linter.load_plugin_modules([plugin])
except ImportError:
errors.append(self._error_message(profile_path, f"Could not load plugin {plugin}"))
for msg_id in prospector_config.get_disabled_messages("pylint"):
try:
linter.disable(msg_id)
except UnknownMessageError:
# If the msg_id doesn't exist in PyLint any more,
# don't worry about it.
pass
options = prospector_config.tool_options("pylint")
for checker in linter.get_checkers():
if not hasattr(checker, "options"):
continue
for option in checker.options:
if option[0] in options:
checker.set_option(option[0], options[option[0]])
# The warnings about disabling warnings are useful for figuring out
# with other tools to suppress messages from. For example, an unused
# import which is disabled with 'pylint disable=unused-import' will
# still generate an 'FL0001' unused import warning from pyflakes.
# Using the information from these messages, we can figure out what
# was disabled.
linter.disable("locally-disabled") # notification about disabling a message
linter.enable("file-ignored") # notification about disabling an entire file
linter.enable("suppressed-message") # notification about a message being suppressed
linter.disable("deprecated-pragma") # notification about use of deprecated 'pragma' option
max_line_length = prospector_config.max_line_length
for checker in linter.get_checkers():
if not hasattr(checker, "options"):
continue
for option in checker.options:
if max_line_length is not None:
if option[0] == "max-line-length":
checker.set_option("max-line-length", max_line_length)
return errors
def _error_message(self, filepath, message):
location = Location(filepath, None, None, 0, 0)
return Message("prospector", "config-problem", location, message)
def _pylintrc_configure(self, pylintrc, linter):
errors = []
are_plugins_loaded = linter.config_from_file(pylintrc)
if not are_plugins_loaded and hasattr(linter.config, "load_plugins"):
for plugin in linter.config.load_plugins:
try:
linter.load_plugin_modules([plugin])
except ImportError:
errors.append(self._error_message(pylintrc, f"Could not load plugin {plugin}"))
return errors
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def configure(self, prospector_config, found_files: FileFinder):
extra_sys_path = found_files.make_syspath()
check_paths = self._get_pylint_check_paths(found_files)
pylint_options = prospector_config.tool_options("pylint")
self._set_path_finder(extra_sys_path, pylint_options)
linter = ProspectorLinter(found_files)
config_messages, configured_by = self._get_pylint_configuration(
check_paths, linter, prospector_config, pylint_options
)
# we don't want similarity reports right now
linter.disable("similarities")
# use the collector 'reporter' to simply gather the messages
# given by PyLint
self._collector = Collector(linter.msgs_store)
linter.set_reporter(self._collector)
if linter.config.jobs == 0:
linter.config.jobs = _cpu_count()
self._linter = linter
return configured_by, config_messages
def _set_path_finder(self, extra_sys_path: List[Path], pylint_options):
# insert the target path into the system path to get correct behaviour
self._orig_sys_path = sys.path
if not pylint_options.get("use_pylint_default_path_finder"):
sys.path = sys.path + [str(path.absolute()) for path in extra_sys_path]
def _get_pylint_check_paths(self, found_files: FileFinder) -> List[Path]:
# create a list of packages, but don't include packages which are
# subpackages of others as checks will be duplicated
check_paths = set()
modules = found_files.python_modules
packages = found_files.python_packages
packages.sort(key=lambda p: len(str(p)))
# don't add modules that are in known packages
for module in modules:
for package in packages:
if _is_in_dir(module, package):
break
else:
check_paths.add(module)
# sort from earlier packages first...
for idx, package in enumerate(packages):
# yuck o(n2) but... temporary
for prev_pkg in packages[:idx]:
if _is_in_dir(package, prev_pkg):
# this is a sub-package of a package we know about
break
else:
# we should care about this one
check_paths.add(package)
# need to sort to make sure multiple runs are deterministic
return sorted(check_paths)
def _get_pylint_configuration(
self, check_paths: List[Path], linter: ProspectorLinter, prospector_config, pylint_options
):
self._args = linter.load_command_line_configuration(str(path) for path in check_paths)
linter.load_default_plugins()
config_messages = self._prospector_configure(prospector_config, linter)
configured_by = None
if prospector_config.use_external_config("pylint"):
# try to find a .pylintrc
pylintrc = pylint_options.get("config_file")
external_config = prospector_config.external_config_location("pylint")
pylintrc = pylintrc or external_config or find_pylintrc()
if pylintrc is None: # nothing explicitly configured
for possible in (".pylintrc", "pylintrc", "pyproject.toml", "setup.cfg"):
pylintrc_path = os.path.join(prospector_config.workdir, possible)
# TODO: pyproject and setup.cfg might not actually have any pylint config
# in, they should be skipped in that case
if os.path.exists(pylintrc_path):
pylintrc = pylintrc_path
break
if pylintrc is not None:
# load it!
configured_by = pylintrc
config_messages += self._pylintrc_configure(pylintrc, linter)
return config_messages, configured_by
def _combine_w0614(self, messages):
"""
For the "unused import from wildcard import" messages,
we want to combine all warnings about the same line into
a single message.
"""
by_loc = defaultdict(list)
out = []
for message in messages:
if message.code == "unused-wildcard-import":
by_loc[message.location].append(message)
else:
out.append(message)
for location, message_list in by_loc.items():
names = []
for msg in message_list:
names.append(_UNUSED_WILDCARD_IMPORT_RE.match(msg.message).group(1))
msgtxt = "Unused imports from wildcard import: %s" % ", ".join(names)
combined_message = Message("pylint", "unused-wildcard-import", location, msgtxt)
out.append(combined_message)
return out
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def combine(self, messages):
"""
Combine repeated messages.
Some error messages are repeated, causing many errors where
only one is strictly necessary.
For example, having a wildcard import will result in one
'Unused Import' warning for every unused import.
This method will combine these into a single warning.
"""
combined = self._combine_w0614(messages)
return sorted(combined)
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def run(self, found_files) -> List[Message]:
self._linter.check(self._args)
sys.path = self._orig_sys_path
messages = self._collector.get_messages()
return self.combine(messages)