| """Python part of the warnings subsystem.""" |
| |
| # Note: function level imports should *not* be used |
| # in this module as it may cause import lock deadlock. |
| # See bug 683658. |
| import linecache |
| import sys |
| import types |
| |
| __all__ = ["warn", "showwarning", "formatwarning", "filterwarnings", |
| "resetwarnings", "catch_warnings"] |
| |
| |
| def warnpy3k(message, category=None, stacklevel=1): |
| """Issue a deprecation warning for Python 3.x related changes. |
| |
| Warnings are omitted unless Python is started with the -3 option. |
| """ |
| if sys.py3kwarning: |
| if category is None: |
| category = DeprecationWarning |
| warn(message, category, stacklevel+1) |
| |
| def _show_warning(message, category, filename, lineno, file=None, line=None): |
| """Hook to write a warning to a file; replace if you like.""" |
| if file is None: |
| file = sys.stderr |
| try: |
| file.write(formatwarning(message, category, filename, lineno, line)) |
| except IOError: |
| pass # the file (probably stderr) is invalid - this warning gets lost. |
| # Keep a worrking version around in case the deprecation of the old API is |
| # triggered. |
| showwarning = _show_warning |
| |
| def formatwarning(message, category, filename, lineno, line=None): |
| """Function to format a warning the standard way.""" |
| s = "%s:%s: %s: %s\n" % (filename, lineno, category.__name__, message) |
| line = linecache.getline(filename, lineno) if line is None else line |
| if line: |
| line = line.strip() |
| s += " %s\n" % line |
| return s |
| |
| def filterwarnings(action, message="", category=Warning, module="", lineno=0, |
| append=0): |
| """Insert an entry into the list of warnings filters (at the front). |
| |
| Use assertions to check that all arguments have the right type.""" |
| import re |
| assert action in ("error", "ignore", "always", "default", "module", |
| "once"), "invalid action: %r" % (action,) |
| assert isinstance(message, basestring), "message must be a string" |
| assert isinstance(category, (type, types.ClassType)), \ |
| "category must be a class" |
| assert issubclass(category, Warning), "category must be a Warning subclass" |
| assert isinstance(module, basestring), "module must be a string" |
| assert isinstance(lineno, int) and lineno >= 0, \ |
| "lineno must be an int >= 0" |
| item = (action, re.compile(message, re.I), category, |
| re.compile(module), lineno) |
| if append: |
| filters.append(item) |
| else: |
| filters.insert(0, item) |
| |
| def simplefilter(action, category=Warning, lineno=0, append=0): |
| """Insert a simple entry into the list of warnings filters (at the front). |
| |
| A simple filter matches all modules and messages. |
| """ |
| 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" |
| item = (action, None, category, None, lineno) |
| if append: |
| filters.append(item) |
| else: |
| filters.insert(0, item) |
| |
| def resetwarnings(): |
| """Clear the list of warning filters, so that no filters are active.""" |
| filters[:] = [] |
| |
| 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, msg: |
| print >>sys.stderr, "Invalid -W option ignored:", msg |
| |
| # Helper for _processoptions() |
| def _setoption(arg): |
| import re |
| 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) |
| message = re.escape(message) |
| category = _getcategory(category) |
| module = re.escape(module) |
| if module: |
| module = module + '$' |
| if lineno: |
| try: |
| lineno = int(lineno) |
| if lineno < 0: |
| raise ValueError |
| except (ValueError, OverflowError): |
| raise _OptionError("invalid lineno %r" % (lineno,)) |
| else: |
| lineno = 0 |
| filterwarnings(action, message, category, module, lineno) |
| |
| # Helper for _setoption() |
| def _getaction(action): |
| if not action: |
| return "default" |
| if action == "all": return "always" # Alias |
| for a in ('default', 'always', 'ignore', 'module', 'once', 'error'): |
| if a.startswith(action): |
| return a |
| raise _OptionError("invalid action: %r" % (action,)) |
| |
| # Helper for _setoption() |
| def _getcategory(category): |
| import re |
| if not category: |
| return Warning |
| if re.match("^[a-zA-Z0-9_]+$", category): |
| try: |
| cat = eval(category) |
| except NameError: |
| raise _OptionError("unknown warning category: %r" % (category,)) |
| else: |
| i = category.rfind(".") |
| module = category[:i] |
| klass = category[i+1:] |
| try: |
| m = __import__(module, None, None, [klass]) |
| except ImportError: |
| raise _OptionError("invalid module name: %r" % (module,)) |
| try: |
| cat = getattr(m, klass) |
| except AttributeError: |
| raise _OptionError("unknown warning category: %r" % (category,)) |
| if not issubclass(cat, Warning): |
| raise _OptionError("invalid warning category: %r" % (category,)) |
| return cat |
| |
| |
| # Code typically replaced by _warnings |
| def warn(message, category=None, stacklevel=1): |
| """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 |
| assert issubclass(category, Warning) |
| # Get context information |
| try: |
| caller = sys._getframe(stacklevel) |
| except ValueError: |
| globals = sys.__dict__ |
| lineno = 1 |
| else: |
| globals = caller.f_globals |
| lineno = caller.f_lineno |
| if '__name__' in globals: |
| module = globals['__name__'] |
| else: |
| module = "<string>" |
| filename = globals.get('__file__') |
| if filename: |
| fnl = filename.lower() |
| if fnl.endswith((".pyc", ".pyo")): |
| filename = filename[:-1] |
| else: |
| if module == "__main__": |
| try: |
| filename = sys.argv[0] |
| except AttributeError: |
| # embedded interpreters don't have sys.argv, see bug #839151 |
| filename = '__main__' |
| if not filename: |
| filename = module |
| registry = globals.setdefault("__warningregistry__", {}) |
| warn_explicit(message, category, filename, lineno, module, registry, |
| globals) |
| |
| def warn_explicit(message, category, filename, lineno, |
| module=None, registry=None, module_globals=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 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": |
| registry[key] = 1 |
| return |
| |
| # Prime the linecache for formatting, in case the |
| # "file" is actually in a zipfile or something. |
| 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)) |
| # Warn if showwarning() does not support the 'line' argument. |
| # Don't use 'inspect' as it relies on an extension module, which break the |
| # build thanks to 'warnings' being imported by setup.py. |
| fxn_code = None |
| if hasattr(showwarning, 'func_code'): |
| fxn_code = showwarning.func_code |
| elif hasattr(showwarning, '__func__'): |
| fxn_code = showwarning.__func__.func_code |
| if fxn_code: |
| args = fxn_code.co_varnames[:fxn_code.co_argcount] |
| CO_VARARGS = 0x4 |
| if 'line' not in args and not fxn_code.co_flags & CO_VARARGS: |
| showwarning_msg = ("functions overriding warnings.showwarning() " |
| "must support the 'line' argument") |
| if message == showwarning_msg: |
| _show_warning(message, category, filename, lineno) |
| else: |
| warn(showwarning_msg, DeprecationWarning) |
| # Print message and context |
| showwarning(message, category, filename, lineno) |
| |
| |
| class WarningMessage(object): |
| |
| """Holds the result of a single showwarning() call.""" |
| |
| _WARNING_DETAILS = ("message", "category", "filename", "lineno", "file", |
| "line") |
| |
| def __init__(self, message, category, filename, lineno, file=None, |
| line=None): |
| local_values = locals() |
| for attr in self._WARNING_DETAILS: |
| setattr(self, attr, local_values[attr]) |
| 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._showwarning = self._module.showwarning |
| if self._record: |
| log = [] |
| def showwarning(*args, **kwargs): |
| log.append(WarningMessage(*args, **kwargs)) |
| self._module.showwarning = showwarning |
| 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.showwarning = self._showwarning |
| |
| |
| # 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. |
| _warnings_defaults = False |
| try: |
| from _warnings import (filters, default_action, once_registry, |
| warn, warn_explicit) |
| defaultaction = default_action |
| onceregistry = once_registry |
| _warnings_defaults = True |
| except ImportError: |
| filters = [] |
| defaultaction = "default" |
| onceregistry = {} |
| |
| |
| # Module initialization |
| _processoptions(sys.warnoptions) |
| if not _warnings_defaults: |
| simplefilter("ignore", category=PendingDeprecationWarning, append=1) |
| simplefilter("ignore", category=ImportWarning, append=1) |
| bytes_warning = sys.flags.bytes_warning |
| if bytes_warning > 1: |
| bytes_action = "error" |
| elif bytes_warning: |
| bytes_action = "default" |
| else: |
| bytes_action = "ignore" |
| simplefilter(bytes_action, category=BytesWarning, append=1) |
| del _warnings_defaults |