# $Id: peps.py 8527 2020-07-14 16:41:15Z milde $
# Author: David Goodger <goodger@python.org>
# Copyright: This module has been placed in the public domain.
"""
Transforms for PEP processing.
- `Headers`: Used to transform a PEP's initial RFC-2822 header. It remains a
field list, but some entries get processed.
- `Contents`: Auto-inserts a table of contents.
- `PEPZero`: Special processing for PEP 0.
"""
__docformat__ = 'reStructuredText'
import sys
import os
import re
import time
from docutils import nodes, utils, languages
from docutils import ApplicationError, DataError
from docutils.transforms import Transform, TransformError
from docutils.transforms import parts, references, misc
class Headers(Transform):
"""
Process fields in a PEP's initial RFC-2822 header.
"""
default_priority = 360
pep_url = 'pep-%04d'
pep_cvs_url = ('http://hg.python.org'
'/peps/file/default/pep-%04d.txt')
rcs_keyword_substitutions = (
(re.compile(r'\$' r'RCSfile: (.+),v \$$', re.IGNORECASE), r'\1'),
(re.compile(r'\$[a-zA-Z]+: (.+) \$$'), r'\1'),)
def apply(self):
if not len(self.document):
# @@@ replace these DataErrors with proper system messages
raise DataError('Document tree is empty.')
header = self.document[0]
if not isinstance(header, nodes.field_list) or \
'rfc2822' not in header['classes']:
raise DataError('Document does not begin with an RFC-2822 '
'header; it is not a PEP.')
pep = None
for field in header:
if field[0].astext().lower() == 'pep': # should be the first field
value = field[1].astext()
try:
pep = int(value)
cvs_url = self.pep_cvs_url % pep
except ValueError:
pep = value
cvs_url = None
msg = self.document.reporter.warning(
'"PEP" header must contain an integer; "%s" is an '
'invalid value.' % pep, base_node=field)
msgid = self.document.set_id(msg)
prb = nodes.problematic(value, value or '(none)',
refid=msgid)
prbid = self.document.set_id(prb)
msg.add_backref(prbid)
if len(field[1]):
field[1][0][:] = [prb]
else:
field[1] += nodes.paragraph('', '', prb)
break
if pep is None:
raise DataError('Document does not contain an RFC-2822 "PEP" '
'header.')
if pep == 0:
# Special processing for PEP 0.
pending = nodes.pending(PEPZero)
self.document.insert(1, pending)
self.document.note_pending(pending)
if len(header) < 2 or header[1][0].astext().lower() != 'title':
raise DataError('No title!')
for field in header:
name = field[0].astext().lower()
body = field[1]
if len(body) > 1:
raise DataError('PEP header field body contains multiple '
'elements:\n%s' % field.pformat(level=1))
elif len(body) == 1:
if not isinstance(body[0], nodes.paragraph):
raise DataError('PEP header field body may only contain '
'a single paragraph:\n%s'
% field.pformat(level=1))
elif name == 'last-modified':
try:
date = time.strftime(
'%d-%b-%Y',
time.localtime(os.stat(self.document['source'])[8]))
except OSError:
date = 'unknown'
if cvs_url:
body += nodes.paragraph(
'', '', nodes.reference('', date, refuri=cvs_url))
else:
# empty
continue
para = body[0]
if name == 'author':
for node in para:
if isinstance(node, nodes.reference):
node.replace_self(mask_email(node))
elif name == 'discussions-to':
for node in para:
if isinstance(node, nodes.reference):
node.replace_self(mask_email(node, pep))
elif name in ('replaces', 'replaced-by', 'requires'):
newbody = []
space = nodes.Text(' ')
for refpep in re.split(r',?\s+', body.astext()):
pepno = int(refpep)
newbody.append(nodes.reference(
refpep, refpep,
refuri=(self.document.settings.pep_base_url
+ self.pep_url % pepno)))
newbody.append(space)
para[:] = newbody[:-1] # drop trailing space
elif name == 'last-modified':
utils.clean_rcs_keywords(para, self.rcs_keyword_substitutions)
if cvs_url:
date = para.astext()
para[:] = [nodes.reference('', date, refuri=cvs_url)]
elif name == 'content-type':
pep_type = para.astext()
uri = self.document.settings.pep_base_url + self.pep_url % 12
para[:] = [nodes.reference('', pep_type, refuri=uri)]
elif name == 'version' and len(body):
utils.clean_rcs_keywords(para, self.rcs_keyword_substitutions)
class Contents(Transform):
"""
Insert an empty table of contents topic and a transform placeholder into
the document after the RFC 2822 header.
"""
default_priority = 380
def apply(self):
language = languages.get_language(self.document.settings.language_code,
self.document.reporter)
name = language.labels['contents']
title = nodes.title('', name)
topic = nodes.topic('', title, classes=['contents'])
name = nodes.fully_normalize_name(name)
if not self.document.has_name(name):
topic['names'].append(name)
self.document.note_implicit_target(topic)
pending = nodes.pending(parts.Contents)
topic += pending
self.document.insert(1, topic)
self.document.note_pending(pending)
class TargetNotes(Transform):
"""
Locate the "References" section, insert a placeholder for an external
target footnote insertion transform at the end, and schedule the
transform to run immediately.
"""
default_priority = 520
def apply(self):
doc = self.document
i = len(doc) - 1
refsect = copyright = None
while i >= 0 and isinstance(doc[i], nodes.section):
title_words = doc[i][0].astext().lower().split()
if 'references' in title_words:
refsect = doc[i]
break
elif 'copyright' in title_words:
copyright = i
i -= 1
if not refsect:
refsect = nodes.section()
refsect += nodes.title('', 'References')
doc.set_id(refsect)
if copyright:
# Put the new "References" section before "Copyright":
doc.insert(copyright, refsect)
else:
# Put the new "References" section at end of doc:
doc.append(refsect)
pending = nodes.pending(references.TargetNotes)
refsect.append(pending)
self.document.note_pending(pending, 0)
pending = nodes.pending(misc.CallBack,
details={'callback': self.cleanup_callback})
refsect.append(pending)
self.document.note_pending(pending, 1)
def cleanup_callback(self, pending):
"""
Remove an empty "References" section.
Called after the `references.TargetNotes` transform is complete.
"""
if len(pending.parent) == 2: # <title> and <pending>
pending.parent.parent.remove(pending.parent)
class PEPZero(Transform):
"""
Special processing for PEP 0.
"""
default_priority =760
def apply(self):
visitor = PEPZeroSpecial(self.document)
self.document.walk(visitor)
self.startnode.parent.remove(self.startnode)
class PEPZeroSpecial(nodes.SparseNodeVisitor):
"""
Perform the special processing needed by PEP 0:
- Mask email addresses.
- Link PEP numbers in the second column of 4-column tables to the PEPs
themselves.
"""
pep_url = Headers.pep_url
def unknown_visit(self, node):
pass
def visit_reference(self, node):
node.replace_self(mask_email(node))
def visit_field_list(self, node):
if 'rfc2822' in node['classes']:
raise nodes.SkipNode
def visit_tgroup(self, node):
self.pep_table = node['cols'] == 4
self.entry = 0
def visit_colspec(self, node):
self.entry += 1
if self.pep_table and self.entry == 2:
node['classes'].append('num')
def visit_row(self, node):
self.entry = 0
def visit_entry(self, node):
self.entry += 1
if self.pep_table and self.entry == 2 and len(node) == 1:
node['classes'].append('num')
p = node[0]
if isinstance(p, nodes.paragraph) and len(p) == 1:
text = p.astext()
try:
pep = int(text)
ref = (self.document.settings.pep_base_url
+ self.pep_url % pep)
p[0] = nodes.reference(text, text, refuri=ref)
except ValueError:
pass
non_masked_addresses = ('peps@python.org',
'python-list@python.org',
'python-dev@python.org')
def mask_email(ref, pepno=None):
"""
Mask the email address in `ref` and return a replacement node.
`ref` is returned unchanged if it contains no email address.
For email addresses such as "user@host", mask the address as "user at
host" (text) to thwart simple email address harvesters (except for those
listed in `non_masked_addresses`). If a PEP number (`pepno`) is given,
return a reference including a default email subject.
"""
if ref.hasattr('refuri') and ref['refuri'].startswith('mailto:'):
if ref['refuri'][8:] in non_masked_addresses:
replacement = ref[0]
else:
replacement_text = ref.astext().replace('@', ' at ')
replacement = nodes.raw('', replacement_text, format='html')
if pepno is None:
return replacement
else:
ref['refuri'] += '?subject=PEP%%20%s' % pepno
ref[:] = [replacement]
return ref
else:
return ref