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β¦H-17618) No longer import the re module if it is not needed.
| """Python part of the warnings subsystem.""" | |
| import sys | |
| __all__ = ["warn", "warn_explicit", "showwarning", | |
| "formatwarning", "filterwarnings", "simplefilter", | |
| "resetwarnings", "catch_warnings"] | |
| def showwarning(message, category, filename, lineno, file=None, line=None): | |
| """Hook to write a warning to a file; replace if you like.""" | |
| msg = WarningMessage(message, category, filename, lineno, file, line) | |
| _showwarnmsg_impl(msg) | |
| def formatwarning(message, category, filename, lineno, line=None): | |
| """Function to format a warning the standard way.""" | |
| msg = WarningMessage(message, category, filename, lineno, None, line) | |
| return _formatwarnmsg_impl(msg) | |
| def _showwarnmsg_impl(msg): | |
| file = msg.file | |
| if file is None: | |
| file = sys.stderr | |
| if file is None: | |
| # sys.stderr is None when run with pythonw.exe: | |
| # warnings get lost | |
| return | |
| text = _formatwarnmsg(msg) | |
| try: | |
| file.write(text) | |
| except OSError: | |
| # the file (probably stderr) is invalid - this warning gets lost. | |
| pass | |
| def _formatwarnmsg_impl(msg): | |
| category = msg.category.__name__ | |
| s = f"{msg.filename}:{msg.lineno}: {category}: {msg.message}\n" | |
| if msg.line is None: | |
| try: | |
| import linecache | |
| line = linecache.getline(msg.filename, msg.lineno) | |
| except Exception: | |
| # When a warning is logged during Python shutdown, linecache | |
| # and the import machinery don't work anymore | |
| line = None | |
| linecache = None | |
| else: | |
| line = msg.line | |
| if line: | |
| line = line.strip() | |
| s += " %s\n" % line | |
| if msg.source is not None: | |
| try: | |
| import tracemalloc | |
| # Logging a warning should not raise a new exception: | |
| # catch Exception, not only ImportError and RecursionError. | |
| except Exception: | |
| # don't suggest to enable tracemalloc if it's not available | |
| tracing = True | |
| tb = None | |
| else: | |
| tracing = tracemalloc.is_tracing() | |
| try: | |
| tb = tracemalloc.get_object_traceback(msg.source) | |
| except Exception: | |
| # When a warning is logged during Python shutdown, tracemalloc | |
| # and the import machinery don't work anymore | |
| tb = None | |
| if tb is not None: | |
| s += 'Object allocated at (most recent call last):\n' | |
| for frame in tb: | |
| s += (' File "%s", lineno %s\n' | |
| % (frame.filename, frame.lineno)) | |
| try: | |
| if linecache is not None: | |
| line = linecache.getline(frame.filename, frame.lineno) | |
| else: | |
| line = None | |
| except Exception: | |
| line = None | |
| if line: | |
| line = line.strip() | |
| s += ' %s\n' % line | |
| elif not tracing: | |
| s += (f'{category}: Enable tracemalloc to get the object ' | |
| f'allocation traceback\n') | |
| return s | |
| # Keep a reference to check if the function was replaced | |
| _showwarning_orig = showwarning | |
| def _showwarnmsg(msg): | |
| """Hook to write a warning to a file; replace if you like.""" | |
| try: | |
| sw = showwarning | |
| except NameError: | |
| pass | |
| else: | |
| if sw is not _showwarning_orig: | |
| # warnings.showwarning() was replaced | |
| if not callable(sw): | |
| raise TypeError("warnings.showwarning() must be set to a " | |
| "function or method") | |
| sw(msg.message, msg.category, msg.filename, msg.lineno, | |
| msg.file, msg.line) | |
| return | |
| _showwarnmsg_impl(msg) | |
| # Keep a reference to check if the function was replaced | |
| _formatwarning_orig = formatwarning | |
| def _formatwarnmsg(msg): | |
| """Function to format a warning the standard way.""" | |
| try: | |
| fw = formatwarning | |
| except NameError: | |
| pass | |
| else: | |
| if fw is not _formatwarning_orig: | |
| # warnings.formatwarning() was replaced | |
| return fw(msg.message, msg.category, | |
| msg.filename, msg.lineno, msg.line) | |
| return _formatwarnmsg_impl(msg) | |
| def filterwarnings(action, message="", category=Warning, module="", lineno=0, | |
| append=False): | |
| """Insert an entry into the list of warnings filters (at the front). | |
| 'action' -- one of "error", "ignore", "always", "default", "module", | |
| or "once" | |
| 'message' -- a regex that the warning message must match | |
| 'category' -- a class that the warning must be a subclass of | |
| 'module' -- a regex that the module name must match | |
| 'lineno' -- an integer line number, 0 matches all warnings | |
| 'append' -- if true, append to the list of filters | |
| """ | |
| assert action in ("error", "ignore", "always", "default", "module", | |
| "once"), "invalid action: %r" % (action,) | |
| assert isinstance(message, str), "message must be a string" | |
| assert isinstance(category, type), "category must be a class" | |
| assert issubclass(category, Warning), "category must be a Warning subclass" | |
| assert isinstance(module, str), "module must be a string" | |
| assert isinstance(lineno, int) and lineno >= 0, \ | |
| "lineno must be an int >= 0" | |
| if message or module: | |
| import re | |
| if message: | |
| message = re.compile(message, re.I) | |
| else: | |
| message = None | |
| if module: | |
| module = re.compile(module) | |
| else: | |
| module = None | |
| _add_filter(action, message, category, module, lineno, append=append) | |
| def simplefilter(action, category=Warning, lineno=0, append=False): | |
| """Insert a simple entry into the list of warnings filters (at the front). | |
| A simple filter matches all modules and messages. | |
| 'action' -- one of "error", "ignore", "always", "default", "module", | |
| or "once" | |
| 'category' -- a class that the warning must be a subclass of | |
| 'lineno' -- an integer line number, 0 matches all warnings | |
| 'append' -- if true, append to the list of filters | |
| """ | |
| assert action in ("error", "ignore", "always", "default", "module", | |
| "once"), "invalid action: %r" % (action,) | |
| assert isinstance(lineno, int) and lineno >= 0, \ | |
| "lineno must be an int >= 0" | |
| _add_filter(action, None, category, None, lineno, append=append) | |
| def _add_filter(*item, append): | |
| # Remove possible duplicate filters, so new one will be placed | |
| # in correct place. If append=True and duplicate exists, do nothing. | |
| if not append: | |
| try: | |
| filters.remove(item) | |
| except ValueError: | |
| pass | |
| filters.insert(0, item) | |
| else: | |
| if item not in filters: | |
| filters.append(item) | |
| _filters_mutated() | |
| def resetwarnings(): | |
| """Clear the list of warning filters, so that no filters are active.""" | |
| filters[:] = [] | |
| _filters_mutated() | |
| class _OptionError(Exception): | |
| """Exception used by option processing helpers.""" | |
| pass | |
| # Helper to process -W options passed via sys.warnoptions | |
| def _processoptions(args): | |
| for arg in args: | |
| try: | |
| _setoption(arg) | |
| except _OptionError as msg: | |
| print("Invalid -W option ignored:", msg, file=sys.stderr) | |
| # Helper for _processoptions() | |
| def _setoption(arg): | |
| parts = arg.split(':') | |
| if len(parts) > 5: | |
| raise _OptionError("too many fields (max 5): %r" % (arg,)) | |
| while len(parts) < 5: | |
| parts.append('') | |
| action, message, category, module, lineno = [s.strip() | |
| for s in parts] | |
| action = _getaction(action) | |
| category = _getcategory(category) | |
| if message or module: | |
| import re | |
| if message: | |
| message = re.escape(message) | |
| if module: | |
| module = re.escape(module) + r'\Z' | |
| if lineno: | |
| try: | |
| lineno = int(lineno) | |
| if lineno < 0: | |
| raise ValueError | |
| except (ValueError, OverflowError): | |
| raise _OptionError("invalid lineno %r" % (lineno,)) from None | |
| else: | |
| lineno = 0 | |
| filterwarnings(action, message, category, module, lineno) | |
| # Helper for _setoption() | |
| def _getaction(action): | |
| if not action: | |
| return "default" | |
| if action == "all": return "always" # Alias | |
| for a in ('default', 'always', 'ignore', 'module', 'once', 'error'): | |
| if a.startswith(action): | |
| return a | |
| raise _OptionError("invalid action: %r" % (action,)) | |
| # Helper for _setoption() | |
| def _getcategory(category): | |
| if not category: | |
| return Warning | |
| if '.' not in category: | |
| import builtins as m | |
| klass = category | |
| else: | |
| module, _, klass = category.rpartition('.') | |
| try: | |
| m = __import__(module, None, None, [klass]) | |
| except ImportError: | |
| raise _OptionError("invalid module name: %r" % (module,)) from None | |
| try: | |
| cat = getattr(m, klass) | |
| except AttributeError: | |
| raise _OptionError("unknown warning category: %r" % (category,)) from None | |
| if not issubclass(cat, Warning): | |
| raise _OptionError("invalid warning category: %r" % (category,)) | |
| return cat | |
| def _is_internal_frame(frame): | |
| """Signal whether the frame is an internal CPython implementation detail.""" | |
| filename = frame.f_code.co_filename | |
| return 'importlib' in filename and '_bootstrap' in filename | |
| def _next_external_frame(frame): | |
| """Find the next frame that doesn't involve CPython internals.""" | |
| frame = frame.f_back | |
| while frame is not None and _is_internal_frame(frame): | |
| frame = frame.f_back | |
| return frame | |
| # Code typically replaced by _warnings | |
| def warn(message, category=None, stacklevel=1, source=None): | |
| """Issue a warning, or maybe ignore it or raise an exception.""" | |
| # Check if message is already a Warning object | |
| if isinstance(message, Warning): | |
| category = message.__class__ | |
| # Check category argument | |
| if category is None: | |
| category = UserWarning | |
| if not (isinstance(category, type) and issubclass(category, Warning)): | |
| raise TypeError("category must be a Warning subclass, " | |
| "not '{:s}'".format(type(category).__name__)) | |
| # Get context information | |
| try: | |
| if stacklevel <= 1 or _is_internal_frame(sys._getframe(1)): | |
| # If frame is too small to care or if the warning originated in | |
| # internal code, then do not try to hide any frames. | |
| frame = sys._getframe(stacklevel) | |
| else: | |
| frame = sys._getframe(1) | |
| # Look for one frame less since the above line starts us off. | |
| for x in range(stacklevel-1): | |
| frame = _next_external_frame(frame) | |
| if frame is None: | |
| raise ValueError | |
| except ValueError: | |
| globals = sys.__dict__ | |
| filename = "sys" | |
| lineno = 1 | |
| else: | |
| globals = frame.f_globals | |
| filename = frame.f_code.co_filename | |
| lineno = frame.f_lineno | |
| if '__name__' in globals: | |
| module = globals['__name__'] | |
| else: | |
| module = "<string>" | |
| registry = globals.setdefault("__warningregistry__", {}) | |
| warn_explicit(message, category, filename, lineno, module, registry, | |
| globals, source) | |
| def warn_explicit(message, category, filename, lineno, | |
| module=None, registry=None, module_globals=None, | |
| source=None): | |
| lineno = int(lineno) | |
| if module is None: | |
| module = filename or "<unknown>" | |
| if module[-3:].lower() == ".py": | |
| module = module[:-3] # XXX What about leading pathname? | |
| if registry is None: | |
| registry = {} | |
| if registry.get('version', 0) != _filters_version: | |
| registry.clear() | |
| registry['version'] = _filters_version | |
| if isinstance(message, Warning): | |
| text = str(message) | |
| category = message.__class__ | |
| else: | |
| text = message | |
| message = category(message) | |
| key = (text, category, lineno) | |
| # Quick test for common case | |
| if registry.get(key): | |
| return | |
| # Search the filters | |
| for item in filters: | |
| action, msg, cat, mod, ln = item | |
| if ((msg is None or msg.match(text)) and | |
| issubclass(category, cat) and | |
| (mod is None or mod.match(module)) and | |
| (ln == 0 or lineno == ln)): | |
| break | |
| else: | |
| action = defaultaction | |
| # Early exit actions | |
| if action == "ignore": | |
| return | |
| # Prime the linecache for formatting, in case the | |
| # "file" is actually in a zipfile or something. | |
| import linecache | |
| linecache.getlines(filename, module_globals) | |
| if action == "error": | |
| raise message | |
| # Other actions | |
| if action == "once": | |
| registry[key] = 1 | |
| oncekey = (text, category) | |
| if onceregistry.get(oncekey): | |
| return | |
| onceregistry[oncekey] = 1 | |
| elif action == "always": | |
| pass | |
| elif action == "module": | |
| registry[key] = 1 | |
| altkey = (text, category, 0) | |
| if registry.get(altkey): | |
| return | |
| registry[altkey] = 1 | |
| elif action == "default": | |
| registry[key] = 1 | |
| else: | |
| # Unrecognized actions are errors | |
| raise RuntimeError( | |
| "Unrecognized action (%r) in warnings.filters:\n %s" % | |
| (action, item)) | |
| # Print message and context | |
| msg = WarningMessage(message, category, filename, lineno, source) | |
| _showwarnmsg(msg) | |
| class WarningMessage(object): | |
| _WARNING_DETAILS = ("message", "category", "filename", "lineno", "file", | |
| "line", "source") | |
| def __init__(self, message, category, filename, lineno, file=None, | |
| line=None, source=None): | |
| self.message = message | |
| self.category = category | |
| self.filename = filename | |
| self.lineno = lineno | |
| self.file = file | |
| self.line = line | |
| self.source = source | |
| self._category_name = category.__name__ if category else None | |
| def __str__(self): | |
| return ("{message : %r, category : %r, filename : %r, lineno : %s, " | |
| "line : %r}" % (self.message, self._category_name, | |
| self.filename, self.lineno, self.line)) | |
| class catch_warnings(object): | |
| """A context manager that copies and restores the warnings filter upon | |
| exiting the context. | |
| The 'record' argument specifies whether warnings should be captured by a | |
| custom implementation of warnings.showwarning() and be appended to a list | |
| returned by the context manager. Otherwise None is returned by the context | |
| manager. The objects appended to the list are arguments whose attributes | |
| mirror the arguments to showwarning(). | |
| The 'module' argument is to specify an alternative module to the module | |
| named 'warnings' and imported under that name. This argument is only useful | |
| when testing the warnings module itself. | |
| """ | |
| def __init__(self, *, record=False, module=None): | |
| """Specify whether to record warnings and if an alternative module | |
| should be used other than sys.modules['warnings']. | |
| For compatibility with Python 3.0, please consider all arguments to be | |
| keyword-only. | |
| """ | |
| self._record = record | |
| self._module = sys.modules['warnings'] if module is None else module | |
| self._entered = False | |
| def __repr__(self): | |
| args = [] | |
| if self._record: | |
| args.append("record=True") | |
| if self._module is not sys.modules['warnings']: | |
| args.append("module=%r" % self._module) | |
| name = type(self).__name__ | |
| return "%s(%s)" % (name, ", ".join(args)) | |
| def __enter__(self): | |
| if self._entered: | |
| raise RuntimeError("Cannot enter %r twice" % self) | |
| self._entered = True | |
| self._filters = self._module.filters | |
| self._module.filters = self._filters[:] | |
| self._module._filters_mutated() | |
| self._showwarning = self._module.showwarning | |
| self._showwarnmsg_impl = self._module._showwarnmsg_impl | |
| if self._record: | |
| log = [] | |
| self._module._showwarnmsg_impl = log.append | |
| # Reset showwarning() to the default implementation to make sure | |
| # that _showwarnmsg() calls _showwarnmsg_impl() | |
| self._module.showwarning = self._module._showwarning_orig | |
| return log | |
| else: | |
| return None | |
| def __exit__(self, *exc_info): | |
| if not self._entered: | |
| raise RuntimeError("Cannot exit %r without entering first" % self) | |
| self._module.filters = self._filters | |
| self._module._filters_mutated() | |
| self._module.showwarning = self._showwarning | |
| self._module._showwarnmsg_impl = self._showwarnmsg_impl | |
| # Private utility function called by _PyErr_WarnUnawaitedCoroutine | |
| def _warn_unawaited_coroutine(coro): | |
| msg_lines = [ | |
| f"coroutine '{coro.__qualname__}' was never awaited\n" | |
| ] | |
| if coro.cr_origin is not None: | |
| import linecache, traceback | |
| def extract(): | |
| for filename, lineno, funcname in reversed(coro.cr_origin): | |
| line = linecache.getline(filename, lineno) | |
| yield (filename, lineno, funcname, line) | |
| msg_lines.append("Coroutine created at (most recent call last)\n") | |
| msg_lines += traceback.format_list(list(extract())) | |
| msg = "".join(msg_lines).rstrip("\n") | |
| # Passing source= here means that if the user happens to have tracemalloc | |
| # enabled and tracking where the coroutine was created, the warning will | |
| # contain that traceback. This does mean that if they have *both* | |
| # coroutine origin tracking *and* tracemalloc enabled, they'll get two | |
| # partially-redundant tracebacks. If we wanted to be clever we could | |
| # probably detect this case and avoid it, but for now we don't bother. | |
| warn(msg, category=RuntimeWarning, stacklevel=2, source=coro) | |
| # filters contains a sequence of filter 5-tuples | |
| # The components of the 5-tuple are: | |
| # - an action: error, ignore, always, default, module, or once | |
| # - a compiled regex that must match the warning message | |
| # - a class representing the warning category | |
| # - a compiled regex that must match the module that is being warned | |
| # - a line number for the line being warning, or 0 to mean any line | |
| # If either if the compiled regexs are None, match anything. | |
| try: | |
| from _warnings import (filters, _defaultaction, _onceregistry, | |
| warn, warn_explicit, _filters_mutated) | |
| defaultaction = _defaultaction | |
| onceregistry = _onceregistry | |
| _warnings_defaults = True | |
| except ImportError: | |
| filters = [] | |
| defaultaction = "default" | |
| onceregistry = {} | |
| _filters_version = 1 | |
| def _filters_mutated(): | |
| global _filters_version | |
| _filters_version += 1 | |
| _warnings_defaults = False | |
| # Module initialization | |
| _processoptions(sys.warnoptions) | |
| if not _warnings_defaults: | |
| # Several warning categories are ignored by default in regular builds | |
| if not hasattr(sys, 'gettotalrefcount'): | |
| filterwarnings("default", category=DeprecationWarning, | |
| module="__main__", append=1) | |
| simplefilter("ignore", category=DeprecationWarning, append=1) | |
| simplefilter("ignore", category=PendingDeprecationWarning, append=1) | |
| simplefilter("ignore", category=ImportWarning, append=1) | |
| simplefilter("ignore", category=ResourceWarning, append=1) | |
| del _warnings_defaults |