buildframework/helium/external/python/lib/common/docutils-0.5-py2.5.egg/docutils/utils.py
# $Id: utils.py 5040 2007-04-03 17:41:59Z goodger $
# Author: David Goodger <goodger@python.org>
# Copyright: This module has been placed in the public domain.
"""
Miscellaneous utilities for the documentation utilities.
"""
__docformat__ = 'reStructuredText'
import sys
import os
import os.path
import types
import warnings
import unicodedata
from types import StringType, UnicodeType
from docutils import ApplicationError, DataError
from docutils import nodes
class SystemMessage(ApplicationError):
def __init__(self, system_message, level):
Exception.__init__(self, system_message.astext())
self.level = level
class SystemMessagePropagation(ApplicationError): pass
class Reporter:
"""
Info/warning/error reporter and ``system_message`` element generator.
Five levels of system messages are defined, along with corresponding
methods: `debug()`, `info()`, `warning()`, `error()`, and `severe()`.
There is typically one Reporter object per process. A Reporter object is
instantiated with thresholds for reporting (generating warnings) and
halting processing (raising exceptions), a switch to turn debug output on
or off, and an I/O stream for warnings. These are stored as instance
attributes.
When a system message is generated, its level is compared to the stored
thresholds, and a warning or error is generated as appropriate. Debug
messages are produced iff the stored debug switch is on, independently of
other thresholds. Message output is sent to the stored warning stream if
not set to ''.
The Reporter class also employs a modified form of the "Observer" pattern
[GoF95]_ to track system messages generated. The `attach_observer` method
should be called before parsing, with a bound method or function which
accepts system messages. The observer can be removed with
`detach_observer`, and another added in its place.
.. [GoF95] Gamma, Helm, Johnson, Vlissides. *Design Patterns: Elements of
Reusable Object-Oriented Software*. Addison-Wesley, Reading, MA, USA,
1995.
"""
levels = 'DEBUG INFO WARNING ERROR SEVERE'.split()
"""List of names for system message levels, indexed by level."""
# system message level constants:
(DEBUG_LEVEL,
INFO_LEVEL,
WARNING_LEVEL,
ERROR_LEVEL,
SEVERE_LEVEL) = range(5)
def __init__(self, source, report_level, halt_level, stream=None,
debug=0, encoding='ascii', error_handler='replace'):
"""
:Parameters:
- `source`: The path to or description of the source data.
- `report_level`: The level at or above which warning output will
be sent to `stream`.
- `halt_level`: The level at or above which `SystemMessage`
exceptions will be raised, halting execution.
- `debug`: Show debug (level=0) system messages?
- `stream`: Where warning output is sent. Can be file-like (has a
``.write`` method), a string (file name, opened for writing),
'' (empty string, for discarding all stream messages) or
`None` (implies `sys.stderr`; default).
- `encoding`: The encoding for stderr output.
- `error_handler`: The error handler for stderr output encoding.
"""
self.source = source
"""The path to or description of the source data."""
self.encoding = encoding
"""The character encoding for the stderr output."""
self.error_handler = error_handler
"""The character encoding error handler."""
self.debug_flag = debug
"""Show debug (level=0) system messages?"""
self.report_level = report_level
"""The level at or above which warning output will be sent
to `self.stream`."""
self.halt_level = halt_level
"""The level at or above which `SystemMessage` exceptions
will be raised, halting execution."""
if stream is None:
stream = sys.stderr
elif type(stream) in (StringType, UnicodeType):
# Leave stream untouched if it's ''.
if stream != '':
if type(stream) == StringType:
stream = open(stream, 'w')
elif type(stream) == UnicodeType:
stream = open(stream.encode(), 'w')
self.stream = stream
"""Where warning output is sent."""
self.observers = []
"""List of bound methods or functions to call with each system_message
created."""
self.max_level = -1
"""The highest level system message generated so far."""
def set_conditions(self, category, report_level, halt_level,
stream=None, debug=0):
warnings.warn('docutils.utils.Reporter.set_conditions deprecated; '
'set attributes via configuration settings or directly',
DeprecationWarning, stacklevel=2)
self.report_level = report_level
self.halt_level = halt_level
if stream is None:
stream = sys.stderr
self.stream = stream
self.debug_flag = debug
def attach_observer(self, observer):
"""
The `observer` parameter is a function or bound method which takes one
argument, a `nodes.system_message` instance.
"""
self.observers.append(observer)
def detach_observer(self, observer):
self.observers.remove(observer)
def notify_observers(self, message):
for observer in self.observers:
observer(message)
def system_message(self, level, message, *children, **kwargs):
"""
Return a system_message object.
Raise an exception or generate a warning if appropriate.
"""
attributes = kwargs.copy()
if kwargs.has_key('base_node'):
source, line = get_source_line(kwargs['base_node'])
del attributes['base_node']
if source is not None:
attributes.setdefault('source', source)
if line is not None:
attributes.setdefault('line', line)
attributes.setdefault('source', self.source)
msg = nodes.system_message(message, level=level,
type=self.levels[level],
*children, **attributes)
if self.stream and (level >= self.report_level
or self.debug_flag and level == self.DEBUG_LEVEL):
msgtext = msg.astext().encode(self.encoding, self.error_handler)
print >>self.stream, msgtext
if level >= self.halt_level:
raise SystemMessage(msg, level)
if level > self.DEBUG_LEVEL or self.debug_flag:
self.notify_observers(msg)
self.max_level = max(level, self.max_level)
return msg
def debug(self, *args, **kwargs):
"""
Level-0, "DEBUG": an internal reporting issue. Typically, there is no
effect on the processing. Level-0 system messages are handled
separately from the others.
"""
if self.debug_flag:
return self.system_message(self.DEBUG_LEVEL, *args, **kwargs)
def info(self, *args, **kwargs):
"""
Level-1, "INFO": a minor issue that can be ignored. Typically there is
no effect on processing, and level-1 system messages are not reported.
"""
return self.system_message(self.INFO_LEVEL, *args, **kwargs)
def warning(self, *args, **kwargs):
"""
Level-2, "WARNING": an issue that should be addressed. If ignored,
there may be unpredictable problems with the output.
"""
return self.system_message(self.WARNING_LEVEL, *args, **kwargs)
def error(self, *args, **kwargs):
"""
Level-3, "ERROR": an error that should be addressed. If ignored, the
output will contain errors.
"""
return self.system_message(self.ERROR_LEVEL, *args, **kwargs)
def severe(self, *args, **kwargs):
"""
Level-4, "SEVERE": a severe error that must be addressed. If ignored,
the output will contain severe errors. Typically level-4 system
messages are turned into exceptions which halt processing.
"""
return self.system_message(self.SEVERE_LEVEL, *args, **kwargs)
class ExtensionOptionError(DataError): pass
class BadOptionError(ExtensionOptionError): pass
class BadOptionDataError(ExtensionOptionError): pass
class DuplicateOptionError(ExtensionOptionError): pass
def extract_extension_options(field_list, options_spec):
"""
Return a dictionary mapping extension option names to converted values.
:Parameters:
- `field_list`: A flat field list without field arguments, where each
field body consists of a single paragraph only.
- `options_spec`: Dictionary mapping known option names to a
conversion function such as `int` or `float`.
:Exceptions:
- `KeyError` for unknown option names.
- `ValueError` for invalid option values (raised by the conversion
function).
- `TypeError` for invalid option value types (raised by conversion
function).
- `DuplicateOptionError` for duplicate options.
- `BadOptionError` for invalid fields.
- `BadOptionDataError` for invalid option data (missing name,
missing data, bad quotes, etc.).
"""
option_list = extract_options(field_list)
option_dict = assemble_option_dict(option_list, options_spec)
return option_dict
def extract_options(field_list):
"""
Return a list of option (name, value) pairs from field names & bodies.
:Parameter:
`field_list`: A flat field list, where each field name is a single
word and each field body consists of a single paragraph only.
:Exceptions:
- `BadOptionError` for invalid fields.
- `BadOptionDataError` for invalid option data (missing name,
missing data, bad quotes, etc.).
"""
option_list = []
for field in field_list:
if len(field[0].astext().split()) != 1:
raise BadOptionError(
'extension option field name may not contain multiple words')
name = str(field[0].astext().lower())
body = field[1]
if len(body) == 0:
data = None
elif len(body) > 1 or not isinstance(body[0], nodes.paragraph) \
or len(body[0]) != 1 or not isinstance(body[0][0], nodes.Text):
raise BadOptionDataError(
'extension option field body may contain\n'
'a single paragraph only (option "%s")' % name)
else:
data = body[0][0].astext()
option_list.append((name, data))
return option_list
def assemble_option_dict(option_list, options_spec):
"""
Return a mapping of option names to values.
:Parameters:
- `option_list`: A list of (name, value) pairs (the output of
`extract_options()`).
- `options_spec`: Dictionary mapping known option names to a
conversion function such as `int` or `float`.
:Exceptions:
- `KeyError` for unknown option names.
- `DuplicateOptionError` for duplicate options.
- `ValueError` for invalid option values (raised by conversion
function).
- `TypeError` for invalid option value types (raised by conversion
function).
"""
options = {}
for name, value in option_list:
convertor = options_spec[name] # raises KeyError if unknown
if convertor is None:
raise KeyError(name) # or if explicitly disabled
if options.has_key(name):
raise DuplicateOptionError('duplicate option "%s"' % name)
try:
options[name] = convertor(value)
except (ValueError, TypeError), detail:
raise detail.__class__('(option: "%s"; value: %r)\n%s'
% (name, value, ' '.join(detail.args)))
return options
class NameValueError(DataError): pass
def extract_name_value(line):
"""
Return a list of (name, value) from a line of the form "name=value ...".
:Exception:
`NameValueError` for invalid input (missing name, missing data, bad
quotes, etc.).
"""
attlist = []
while line:
equals = line.find('=')
if equals == -1:
raise NameValueError('missing "="')
attname = line[:equals].strip()
if equals == 0 or not attname:
raise NameValueError(
'missing attribute name before "="')
line = line[equals+1:].lstrip()
if not line:
raise NameValueError(
'missing value after "%s="' % attname)
if line[0] in '\'"':
endquote = line.find(line[0], 1)
if endquote == -1:
raise NameValueError(
'attribute "%s" missing end quote (%s)'
% (attname, line[0]))
if len(line) > endquote + 1 and line[endquote + 1].strip():
raise NameValueError(
'attribute "%s" end quote (%s) not followed by '
'whitespace' % (attname, line[0]))
data = line[1:endquote]
line = line[endquote+1:].lstrip()
else:
space = line.find(' ')
if space == -1:
data = line
line = ''
else:
data = line[:space]
line = line[space+1:].lstrip()
attlist.append((attname.lower(), data))
return attlist
def new_reporter(source_path, settings):
"""
Return a new Reporter object.
:Parameters:
`source` : string
The path to or description of the source text of the document.
`settings` : optparse.Values object
Runtime settings.
"""
reporter = Reporter(
source_path, settings.report_level, settings.halt_level,
stream=settings.warning_stream, debug=settings.debug,
encoding=settings.error_encoding,
error_handler=settings.error_encoding_error_handler)
return reporter
def new_document(source_path, settings=None):
"""
Return a new empty document object.
:Parameters:
`source_path` : string
The path to or description of the source text of the document.
`settings` : optparse.Values object
Runtime settings. If none provided, a default set will be used.
"""
from docutils import frontend
if settings is None:
settings = frontend.OptionParser().get_default_values()
reporter = new_reporter(source_path, settings)
document = nodes.document(settings, reporter, source=source_path)
document.note_source(source_path, -1)
return document
def clean_rcs_keywords(paragraph, keyword_substitutions):
if len(paragraph) == 1 and isinstance(paragraph[0], nodes.Text):
textnode = paragraph[0]
for pattern, substitution in keyword_substitutions:
match = pattern.search(textnode.data)
if match:
textnode.data = pattern.sub(substitution, textnode.data)
return
def relative_path(source, target):
"""
Build and return a path to `target`, relative to `source` (both files).
If there is no common prefix, return the absolute path to `target`.
"""
source_parts = os.path.abspath(source or 'dummy_file').split(os.sep)
target_parts = os.path.abspath(target).split(os.sep)
# Check first 2 parts because '/dir'.split('/') == ['', 'dir']:
if source_parts[:2] != target_parts[:2]:
# Nothing in common between paths.
# Return absolute path, using '/' for URLs:
return '/'.join(target_parts)
source_parts.reverse()
target_parts.reverse()
while (source_parts and target_parts
and source_parts[-1] == target_parts[-1]):
# Remove path components in common:
source_parts.pop()
target_parts.pop()
target_parts.reverse()
parts = ['..'] * (len(source_parts) - 1) + target_parts
return '/'.join(parts)
def get_stylesheet_reference(settings, relative_to=None):
"""
Retrieve a stylesheet reference from the settings object.
"""
if settings.stylesheet_path:
assert not settings.stylesheet, \
'stylesheet and stylesheet_path are mutually exclusive.'
if relative_to == None:
relative_to = settings._destination
return relative_path(relative_to, settings.stylesheet_path)
else:
return settings.stylesheet
def get_trim_footnote_ref_space(settings):
"""
Return whether or not to trim footnote space.
If trim_footnote_reference_space is not None, return it.
If trim_footnote_reference_space is None, return False unless the
footnote reference style is 'superscript'.
"""
if settings.trim_footnote_reference_space is None:
return hasattr(settings, 'footnote_references') and \
settings.footnote_references == 'superscript'
else:
return settings.trim_footnote_reference_space
def get_source_line(node):
"""
Return the "source" and "line" attributes from the `node` given or from
its closest ancestor.
"""
while node:
if node.source or node.line:
return node.source, node.line
node = node.parent
return None, None
def escape2null(text):
"""Return a string with escape-backslashes converted to nulls."""
parts = []
start = 0
while 1:
found = text.find('\\', start)
if found == -1:
parts.append(text[start:])
return ''.join(parts)
parts.append(text[start:found])
parts.append('\x00' + text[found+1:found+2])
start = found + 2 # skip character after escape
def unescape(text, restore_backslashes=0):
"""
Return a string with nulls removed or restored to backslashes.
Backslash-escaped spaces are also removed.
"""
if restore_backslashes:
return text.replace('\x00', '\\')
else:
for sep in ['\x00 ', '\x00\n', '\x00']:
text = ''.join(text.split(sep))
return text
east_asian_widths = {'W': 2, # Wide
'F': 2, # Full-width (wide)
'Na': 1, # Narrow
'H': 1, # Half-width (narrow)
'N': 1, # Neutral (not East Asian, treated as narrow)
'A': 1} # Ambiguous (s/b wide in East Asian context,
# narrow otherwise, but that doesn't work)
"""Mapping of result codes from `unicodedata.east_asian_width()` to character
column widths."""
def east_asian_column_width(text):
if isinstance(text, types.UnicodeType):
total = 0
for c in text:
total += east_asian_widths[unicodedata.east_asian_width(c)]
return total
else:
return len(text)
if hasattr(unicodedata, 'east_asian_width'):
column_width = east_asian_column_width
else:
column_width = len
def uniq(L):
r = []
for item in L:
if not item in r:
r.append(item)
return r
class DependencyList:
"""
List of dependencies, with file recording support.
Note that the output file is not automatically closed. You have
to explicitly call the close() method.
"""
def __init__(self, output_file=None, dependencies=[]):
"""
Initialize the dependency list, automatically setting the
output file to `output_file` (see `set_output()`) and adding
all supplied dependencies.
"""
self.set_output(output_file)
for i in dependencies:
self.add(i)
def set_output(self, output_file):
"""
Set the output file and clear the list of already added
dependencies.
`output_file` must be a string. The specified file is
immediately overwritten.
If output_file is '-', the output will be written to stdout.
If it is None, no file output is done when calling add().
"""
self.list = []
if output_file == '-':
self.file = sys.stdout
elif output_file:
self.file = open(output_file, 'w')
else:
self.file = None
def add(self, filename):
"""
If the dependency `filename` has not already been added,
append it to self.list and print it to self.file if self.file
is not None.
"""
if not filename in self.list:
self.list.append(filename)
if self.file is not None:
print >>self.file, filename
def close(self):
"""
Close the output file.
"""
self.file.close()
self.file = None
def __repr__(self):
if self.file:
output_file = self.file.name
else:
output_file = None
return '%s(%r, %s)' % (self.__class__.__name__, output_file, self.list)