| 1 | """Python part of the warnings subsystem."""
|
| 2 |
|
| 3 | # Note: function level imports should *not* be used
|
| 4 | # in this module as it may cause import lock deadlock.
|
| 5 | # See bug 683658.
|
| 6 | import linecache
|
| 7 | import sys
|
| 8 | import types
|
| 9 |
|
| 10 | __all__ = ["warn", "warn_explicit", "showwarning",
|
| 11 | "formatwarning", "filterwarnings", "simplefilter",
|
| 12 | "resetwarnings", "catch_warnings"]
|
| 13 |
|
| 14 |
|
| 15 | def warnpy3k(message, category=None, stacklevel=1):
|
| 16 | """Issue a deprecation warning for Python 3.x related changes.
|
| 17 |
|
| 18 | Warnings are omitted unless Python is started with the -3 option.
|
| 19 | """
|
| 20 | if sys.py3kwarning:
|
| 21 | if category is None:
|
| 22 | category = DeprecationWarning
|
| 23 | warn(message, category, stacklevel+1)
|
| 24 |
|
| 25 | def _show_warning(message, category, filename, lineno, file=None, line=None):
|
| 26 | """Hook to write a warning to a file; replace if you like."""
|
| 27 | if file is None:
|
| 28 | file = sys.stderr
|
| 29 | if file is None:
|
| 30 | # sys.stderr is None - warnings get lost
|
| 31 | return
|
| 32 | try:
|
| 33 | file.write(formatwarning(message, category, filename, lineno, line))
|
| 34 | except (IOError, UnicodeError):
|
| 35 | pass # the file (probably stderr) is invalid - this warning gets lost.
|
| 36 | # Keep a working version around in case the deprecation of the old API is
|
| 37 | # triggered.
|
| 38 | showwarning = _show_warning
|
| 39 |
|
| 40 | def formatwarning(message, category, filename, lineno, line=None):
|
| 41 | """Function to format a warning the standard way."""
|
| 42 | try:
|
| 43 | unicodetype = unicode
|
| 44 | except NameError:
|
| 45 | unicodetype = ()
|
| 46 | try:
|
| 47 | message = str(message)
|
| 48 | except UnicodeEncodeError:
|
| 49 | pass
|
| 50 | s = "%s: %s: %s\n" % (lineno, category.__name__, message)
|
| 51 | line = linecache.getline(filename, lineno) if line is None else line
|
| 52 | if line:
|
| 53 | line = line.strip()
|
| 54 | if isinstance(s, unicodetype) and isinstance(line, str):
|
| 55 | line = unicode(line, 'latin1')
|
| 56 | s += " %s\n" % line
|
| 57 | if isinstance(s, unicodetype) and isinstance(filename, str):
|
| 58 | enc = sys.getfilesystemencoding()
|
| 59 | if enc:
|
| 60 | try:
|
| 61 | filename = unicode(filename, enc)
|
| 62 | except UnicodeDecodeError:
|
| 63 | pass
|
| 64 | s = "%s:%s" % (filename, s)
|
| 65 | return s
|
| 66 |
|
| 67 | def filterwarnings(action, message="", category=Warning, module="", lineno=0,
|
| 68 | append=0):
|
| 69 | """Insert an entry into the list of warnings filters (at the front).
|
| 70 |
|
| 71 | 'action' -- one of "error", "ignore", "always", "default", "module",
|
| 72 | or "once"
|
| 73 | 'message' -- a regex that the warning message must match
|
| 74 | 'category' -- a class that the warning must be a subclass of
|
| 75 | 'module' -- a regex that the module name must match
|
| 76 | 'lineno' -- an integer line number, 0 matches all warnings
|
| 77 | 'append' -- if true, append to the list of filters
|
| 78 | """
|
| 79 | import re
|
| 80 | assert action in ("error", "ignore", "always", "default", "module",
|
| 81 | "once"), "invalid action: %r" % (action,)
|
| 82 | assert isinstance(message, basestring), "message must be a string"
|
| 83 | assert isinstance(category, (type, types.ClassType)), \
|
| 84 | "category must be a class"
|
| 85 | assert issubclass(category, Warning), "category must be a Warning subclass"
|
| 86 | assert isinstance(module, basestring), "module must be a string"
|
| 87 | assert isinstance(lineno, int) and lineno >= 0, \
|
| 88 | "lineno must be an int >= 0"
|
| 89 | item = (action, re.compile(message, re.I), category,
|
| 90 | re.compile(module), lineno)
|
| 91 | if append:
|
| 92 | filters.append(item)
|
| 93 | else:
|
| 94 | filters.insert(0, item)
|
| 95 |
|
| 96 | def simplefilter(action, category=Warning, lineno=0, append=0):
|
| 97 | """Insert a simple entry into the list of warnings filters (at the front).
|
| 98 |
|
| 99 | A simple filter matches all modules and messages.
|
| 100 | 'action' -- one of "error", "ignore", "always", "default", "module",
|
| 101 | or "once"
|
| 102 | 'category' -- a class that the warning must be a subclass of
|
| 103 | 'lineno' -- an integer line number, 0 matches all warnings
|
| 104 | 'append' -- if true, append to the list of filters
|
| 105 | """
|
| 106 | assert action in ("error", "ignore", "always", "default", "module",
|
| 107 | "once"), "invalid action: %r" % (action,)
|
| 108 | assert isinstance(lineno, int) and lineno >= 0, \
|
| 109 | "lineno must be an int >= 0"
|
| 110 | item = (action, None, category, None, lineno)
|
| 111 | if append:
|
| 112 | filters.append(item)
|
| 113 | else:
|
| 114 | filters.insert(0, item)
|
| 115 |
|
| 116 | def resetwarnings():
|
| 117 | """Clear the list of warning filters, so that no filters are active."""
|
| 118 | filters[:] = []
|
| 119 |
|
| 120 | class _OptionError(Exception):
|
| 121 | """Exception used by option processing helpers."""
|
| 122 | pass
|
| 123 |
|
| 124 | # Helper to process -W options passed via sys.warnoptions
|
| 125 | def _processoptions(args):
|
| 126 | for arg in args:
|
| 127 | try:
|
| 128 | _setoption(arg)
|
| 129 | except _OptionError, msg:
|
| 130 | print >>sys.stderr, "Invalid -W option ignored:", msg
|
| 131 |
|
| 132 | # Helper for _processoptions()
|
| 133 | def _setoption(arg):
|
| 134 | import re
|
| 135 | parts = arg.split(':')
|
| 136 | if len(parts) > 5:
|
| 137 | raise _OptionError("too many fields (max 5): %r" % (arg,))
|
| 138 | while len(parts) < 5:
|
| 139 | parts.append('')
|
| 140 | action, message, category, module, lineno = [s.strip()
|
| 141 | for s in parts]
|
| 142 | action = _getaction(action)
|
| 143 | message = re.escape(message)
|
| 144 | category = _getcategory(category)
|
| 145 | module = re.escape(module)
|
| 146 | if module:
|
| 147 | module = module + '$'
|
| 148 | if lineno:
|
| 149 | try:
|
| 150 | lineno = int(lineno)
|
| 151 | if lineno < 0:
|
| 152 | raise ValueError
|
| 153 | except (ValueError, OverflowError):
|
| 154 | raise _OptionError("invalid lineno %r" % (lineno,))
|
| 155 | else:
|
| 156 | lineno = 0
|
| 157 | filterwarnings(action, message, category, module, lineno)
|
| 158 |
|
| 159 | # Helper for _setoption()
|
| 160 | def _getaction(action):
|
| 161 | if not action:
|
| 162 | return "default"
|
| 163 | if action == "all": return "always" # Alias
|
| 164 | for a in ('default', 'always', 'ignore', 'module', 'once', 'error'):
|
| 165 | if a.startswith(action):
|
| 166 | return a
|
| 167 | raise _OptionError("invalid action: %r" % (action,))
|
| 168 |
|
| 169 | # Helper for _setoption()
|
| 170 | def _getcategory(category):
|
| 171 | import re
|
| 172 | if not category:
|
| 173 | return Warning
|
| 174 | if re.match("^[a-zA-Z0-9_]+$", category):
|
| 175 | try:
|
| 176 | cat = eval(category)
|
| 177 | except NameError:
|
| 178 | raise _OptionError("unknown warning category: %r" % (category,))
|
| 179 | else:
|
| 180 | i = category.rfind(".")
|
| 181 | module = category[:i]
|
| 182 | klass = category[i+1:]
|
| 183 | try:
|
| 184 | m = __import__(module, None, None, [klass])
|
| 185 | except ImportError:
|
| 186 | raise _OptionError("invalid module name: %r" % (module,))
|
| 187 | try:
|
| 188 | cat = getattr(m, klass)
|
| 189 | except AttributeError:
|
| 190 | raise _OptionError("unknown warning category: %r" % (category,))
|
| 191 | if not issubclass(cat, Warning):
|
| 192 | raise _OptionError("invalid warning category: %r" % (category,))
|
| 193 | return cat
|
| 194 |
|
| 195 |
|
| 196 | # Code typically replaced by _warnings
|
| 197 | def warn(message, category=None, stacklevel=1):
|
| 198 | """Issue a warning, or maybe ignore it or raise an exception."""
|
| 199 | # Check if message is already a Warning object
|
| 200 | if isinstance(message, Warning):
|
| 201 | category = message.__class__
|
| 202 | # Check category argument
|
| 203 | if category is None:
|
| 204 | category = UserWarning
|
| 205 | assert issubclass(category, Warning)
|
| 206 | # Get context information
|
| 207 | try:
|
| 208 | caller = sys._getframe(stacklevel)
|
| 209 | except ValueError:
|
| 210 | globals = sys.__dict__
|
| 211 | lineno = 1
|
| 212 | else:
|
| 213 | globals = caller.f_globals
|
| 214 | lineno = caller.f_lineno
|
| 215 | if '__name__' in globals:
|
| 216 | module = globals['__name__']
|
| 217 | else:
|
| 218 | module = "<string>"
|
| 219 | filename = globals.get('__file__')
|
| 220 | if filename:
|
| 221 | fnl = filename.lower()
|
| 222 | if fnl.endswith((".pyc", ".pyo")):
|
| 223 | filename = filename[:-1]
|
| 224 | else:
|
| 225 | if module == "__main__":
|
| 226 | try:
|
| 227 | filename = sys.argv[0]
|
| 228 | except AttributeError:
|
| 229 | # embedded interpreters don't have sys.argv, see bug #839151
|
| 230 | filename = '__main__'
|
| 231 | if not filename:
|
| 232 | filename = module
|
| 233 | registry = globals.setdefault("__warningregistry__", {})
|
| 234 | warn_explicit(message, category, filename, lineno, module, registry,
|
| 235 | globals)
|
| 236 |
|
| 237 | def warn_explicit(message, category, filename, lineno,
|
| 238 | module=None, registry=None, module_globals=None):
|
| 239 | lineno = int(lineno)
|
| 240 | if module is None:
|
| 241 | module = filename or "<unknown>"
|
| 242 | if module[-3:].lower() == ".py":
|
| 243 | module = module[:-3] # XXX What about leading pathname?
|
| 244 | if registry is None:
|
| 245 | registry = {}
|
| 246 | if isinstance(message, Warning):
|
| 247 | text = str(message)
|
| 248 | category = message.__class__
|
| 249 | else:
|
| 250 | text = message
|
| 251 | message = category(message)
|
| 252 | key = (text, category, lineno)
|
| 253 | # Quick test for common case
|
| 254 | if registry.get(key):
|
| 255 | return
|
| 256 | # Search the filters
|
| 257 | for item in filters:
|
| 258 | action, msg, cat, mod, ln = item
|
| 259 | if ((msg is None or msg.match(text)) and
|
| 260 | issubclass(category, cat) and
|
| 261 | (mod is None or mod.match(module)) and
|
| 262 | (ln == 0 or lineno == ln)):
|
| 263 | break
|
| 264 | else:
|
| 265 | action = defaultaction
|
| 266 | # Early exit actions
|
| 267 | if action == "ignore":
|
| 268 | registry[key] = 1
|
| 269 | return
|
| 270 |
|
| 271 | # Prime the linecache for formatting, in case the
|
| 272 | # "file" is actually in a zipfile or something.
|
| 273 | linecache.getlines(filename, module_globals)
|
| 274 |
|
| 275 | if action == "error":
|
| 276 | raise message
|
| 277 | # Other actions
|
| 278 | if action == "once":
|
| 279 | registry[key] = 1
|
| 280 | oncekey = (text, category)
|
| 281 | if onceregistry.get(oncekey):
|
| 282 | return
|
| 283 | onceregistry[oncekey] = 1
|
| 284 | elif action == "always":
|
| 285 | pass
|
| 286 | elif action == "module":
|
| 287 | registry[key] = 1
|
| 288 | altkey = (text, category, 0)
|
| 289 | if registry.get(altkey):
|
| 290 | return
|
| 291 | registry[altkey] = 1
|
| 292 | elif action == "default":
|
| 293 | registry[key] = 1
|
| 294 | else:
|
| 295 | # Unrecognized actions are errors
|
| 296 | raise RuntimeError(
|
| 297 | "Unrecognized action (%r) in warnings.filters:\n %s" %
|
| 298 | (action, item))
|
| 299 | # Print message and context
|
| 300 | showwarning(message, category, filename, lineno)
|
| 301 |
|
| 302 |
|
| 303 | class WarningMessage(object):
|
| 304 |
|
| 305 | """Holds the result of a single showwarning() call."""
|
| 306 |
|
| 307 | _WARNING_DETAILS = ("message", "category", "filename", "lineno", "file",
|
| 308 | "line")
|
| 309 |
|
| 310 | def __init__(self, message, category, filename, lineno, file=None,
|
| 311 | line=None):
|
| 312 | local_values = locals()
|
| 313 | for attr in self._WARNING_DETAILS:
|
| 314 | setattr(self, attr, local_values[attr])
|
| 315 | self._category_name = category.__name__ if category else None
|
| 316 |
|
| 317 | def __str__(self):
|
| 318 | return ("{message : %r, category : %r, filename : %r, lineno : %s, "
|
| 319 | "line : %r}" % (self.message, self._category_name,
|
| 320 | self.filename, self.lineno, self.line))
|
| 321 |
|
| 322 |
|
| 323 | class catch_warnings(object):
|
| 324 |
|
| 325 | """A context manager that copies and restores the warnings filter upon
|
| 326 | exiting the context.
|
| 327 |
|
| 328 | The 'record' argument specifies whether warnings should be captured by a
|
| 329 | custom implementation of warnings.showwarning() and be appended to a list
|
| 330 | returned by the context manager. Otherwise None is returned by the context
|
| 331 | manager. The objects appended to the list are arguments whose attributes
|
| 332 | mirror the arguments to showwarning().
|
| 333 |
|
| 334 | The 'module' argument is to specify an alternative module to the module
|
| 335 | named 'warnings' and imported under that name. This argument is only useful
|
| 336 | when testing the warnings module itself.
|
| 337 |
|
| 338 | """
|
| 339 |
|
| 340 | def __init__(self, record=False, module=None):
|
| 341 | """Specify whether to record warnings and if an alternative module
|
| 342 | should be used other than sys.modules['warnings'].
|
| 343 |
|
| 344 | For compatibility with Python 3.0, please consider all arguments to be
|
| 345 | keyword-only.
|
| 346 |
|
| 347 | """
|
| 348 | self._record = record
|
| 349 | self._module = sys.modules['warnings'] if module is None else module
|
| 350 | self._entered = False
|
| 351 |
|
| 352 | def __repr__(self):
|
| 353 | args = []
|
| 354 | if self._record:
|
| 355 | args.append("record=True")
|
| 356 | if self._module is not sys.modules['warnings']:
|
| 357 | args.append("module=%r" % self._module)
|
| 358 | name = type(self).__name__
|
| 359 | return "%s(%s)" % (name, ", ".join(args))
|
| 360 |
|
| 361 | def __enter__(self):
|
| 362 | if self._entered:
|
| 363 | raise RuntimeError("Cannot enter %r twice" % self)
|
| 364 | self._entered = True
|
| 365 | self._filters = self._module.filters
|
| 366 | self._module.filters = self._filters[:]
|
| 367 | self._showwarning = self._module.showwarning
|
| 368 | if self._record:
|
| 369 | log = []
|
| 370 | def showwarning(*args, **kwargs):
|
| 371 | log.append(WarningMessage(*args, **kwargs))
|
| 372 | self._module.showwarning = showwarning
|
| 373 | return log
|
| 374 | else:
|
| 375 | return None
|
| 376 |
|
| 377 | def __exit__(self, *exc_info):
|
| 378 | if not self._entered:
|
| 379 | raise RuntimeError("Cannot exit %r without entering first" % self)
|
| 380 | self._module.filters = self._filters
|
| 381 | self._module.showwarning = self._showwarning
|
| 382 |
|
| 383 |
|
| 384 | # filters contains a sequence of filter 5-tuples
|
| 385 | # The components of the 5-tuple are:
|
| 386 | # - an action: error, ignore, always, default, module, or once
|
| 387 | # - a compiled regex that must match the warning message
|
| 388 | # - a class representing the warning category
|
| 389 | # - a compiled regex that must match the module that is being warned
|
| 390 | # - a line number for the line being warning, or 0 to mean any line
|
| 391 | # If either if the compiled regexs are None, match anything.
|
| 392 | _warnings_defaults = False
|
| 393 | try:
|
| 394 | from _warnings import (filters, default_action, once_registry,
|
| 395 | warn, warn_explicit)
|
| 396 | defaultaction = default_action
|
| 397 | onceregistry = once_registry
|
| 398 | _warnings_defaults = True
|
| 399 | except ImportError:
|
| 400 | filters = []
|
| 401 | defaultaction = "default"
|
| 402 | onceregistry = {}
|
| 403 |
|
| 404 |
|
| 405 | # Module initialization
|
| 406 | _processoptions(sys.warnoptions)
|
| 407 | if not _warnings_defaults:
|
| 408 | silence = [ImportWarning, PendingDeprecationWarning]
|
| 409 | # Don't silence DeprecationWarning if -3 or -Q was used.
|
| 410 | if not sys.py3kwarning and not sys.flags.division_warning:
|
| 411 | silence.append(DeprecationWarning)
|
| 412 | for cls in silence:
|
| 413 | simplefilter("ignore", category=cls)
|
| 414 | bytes_warning = sys.flags.bytes_warning
|
| 415 | if bytes_warning > 1:
|
| 416 | bytes_action = "error"
|
| 417 | elif bytes_warning:
|
| 418 | bytes_action = "default"
|
| 419 | else:
|
| 420 | bytes_action = "ignore"
|
| 421 | simplefilter(bytes_action, category=BytesWarning, append=1)
|
| 422 | del _warnings_defaults
|