cpython/Doc/tools/sphinxext/suspicious.py

255 lines
8.6 KiB
Python

"""
Try to detect suspicious constructs, resembling markup
that has leaked into the final output.
Suspicious lines are reported in a comma-separated-file,
``suspicious.csv``, located in the output directory.
The file is utf-8 encoded, and each line contains four fields:
* document name (normalized)
* line number in the source document
* problematic text
* complete line showing the problematic text in context
It is common to find many false positives. To avoid reporting them
again and again, they may be added to the ``ignored.csv`` file
(located in the configuration directory). The file has the same
format as ``suspicious.csv`` with a few differences:
- each line defines a rule; if the rule matches, the issue
is ignored.
- line number may be empty (that is, nothing between the
commas: ",,"). In this case, line numbers are ignored (the
rule matches anywhere in the file).
- the last field does not have to be a complete line; some
surrounding text (never more than a line) is enough for
context.
Rules are processed sequentially. A rule matches when:
* document names are the same
* problematic texts are the same
* line numbers are close to each other (5 lines up or down)
* the rule text is completely contained into the source line
The simplest way to create the ignored.csv file is by copying
undesired entries from suspicious.csv (possibly trimming the last
field.)
Copyright 2009 Gabriel A. Genellina
"""
import os
import re
import csv
import sys
from docutils import nodes
from sphinx.builders import Builder
detect_all = re.compile(ur'''
::(?=[^=])| # two :: (but NOT ::=)
:[a-zA-Z][a-zA-Z0-9]+| # :foo
`| # ` (seldom used by itself)
(?<!\.)\.\.[ \t]*\w+: # .. foo: (but NOT ... else:)
''', re.UNICODE | re.VERBOSE).finditer
class Rule:
def __init__(self, docname, lineno, issue, line):
"""A rule for ignoring issues"""
self.docname = docname # document to which this rule applies
self.lineno = lineno # line number in the original source;
# this rule matches only near that.
# None -> don't care
self.issue = issue # the markup fragment that triggered this rule
self.line = line # text of the container element (single line only)
self.used = False
def __repr__(self):
return '{0.docname},,{0.issue},{0.line}'.format(self)
class dialect(csv.excel):
"""Our dialect: uses only linefeed as newline."""
lineterminator = '\n'
class CheckSuspiciousMarkupBuilder(Builder):
"""
Checks for possibly invalid markup that may leak into the output.
"""
name = 'suspicious'
def init(self):
# create output file
self.log_file_name = os.path.join(self.outdir, 'suspicious.csv')
open(self.log_file_name, 'w').close()
# load database of previously ignored issues
self.load_rules(os.path.join(os.path.dirname(__file__),
'susp-ignored.csv'))
def get_outdated_docs(self):
return self.env.found_docs
def get_target_uri(self, docname, typ=None):
return ''
def prepare_writing(self, docnames):
pass
def write_doc(self, docname, doctree):
# set when any issue is encountered in this document
self.any_issue = False
self.docname = docname
visitor = SuspiciousVisitor(doctree, self)
doctree.walk(visitor)
def finish(self):
unused_rules = [rule for rule in self.rules if not rule.used]
if unused_rules:
self.warn('Found %s/%s unused rules:' %
(len(unused_rules), len(self.rules)))
for rule in unused_rules:
self.info(repr(rule))
return
def check_issue(self, line, lineno, issue):
if not self.is_ignored(line, lineno, issue):
self.report_issue(line, lineno, issue)
def is_ignored(self, line, lineno, issue):
"""Determine whether this issue should be ignored."""
docname = self.docname
for rule in self.rules:
if rule.docname != docname: continue
if rule.issue != issue: continue
# Both lines must match *exactly*. This is rather strict,
# and probably should be improved.
# Doing fuzzy matches with levenshtein distance could work,
# but that means bringing other libraries...
# Ok, relax that requirement: just check if the rule fragment
# is contained in the document line
if rule.line not in line: continue
# Check both line numbers. If they're "near"
# this rule matches. (lineno=None means "don't care")
if (rule.lineno is not None) and \
abs(rule.lineno - lineno) > 5: continue
# if it came this far, the rule matched
rule.used = True
return True
return False
def report_issue(self, text, lineno, issue):
if not self.any_issue: self.info()
self.any_issue = True
self.write_log_entry(lineno, issue, text)
self.warn('[%s:%d] "%s" found in "%-.120s"' % (
self.docname.encode(sys.getdefaultencoding(),'replace'),
lineno,
issue.encode(sys.getdefaultencoding(),'replace'),
text.strip().encode(sys.getdefaultencoding(),'replace')))
self.app.statuscode = 1
def write_log_entry(self, lineno, issue, text):
f = open(self.log_file_name, 'ab')
writer = csv.writer(f, dialect)
writer.writerow([self.docname.encode('utf-8'),
lineno,
issue.encode('utf-8'),
text.strip().encode('utf-8')])
f.close()
def load_rules(self, filename):
"""Load database of previously ignored issues.
A csv file, with exactly the same format as suspicious.csv
Fields: document name (normalized), line number, issue, surrounding text
"""
self.info("loading ignore rules... ", nonl=1)
self.rules = rules = []
try: f = open(filename, 'rb')
except IOError: return
for i, row in enumerate(csv.reader(f)):
if len(row) != 4:
raise ValueError(
"wrong format in %s, line %d: %s" % (filename, i+1, row))
docname, lineno, issue, text = row
docname = docname.decode('utf-8')
if lineno: lineno = int(lineno)
else: lineno = None
issue = issue.decode('utf-8')
text = text.decode('utf-8')
rule = Rule(docname, lineno, issue, text)
rules.append(rule)
f.close()
self.info('done, %d rules loaded' % len(self.rules))
def get_lineno(node):
"""Obtain line number information for a node."""
lineno = None
while lineno is None and node:
node = node.parent
lineno = node.line
return lineno
def extract_line(text, index):
"""text may be a multiline string; extract
only the line containing the given character index.
>>> extract_line("abc\ndefgh\ni", 6)
>>> 'defgh'
>>> for i in (0, 2, 3, 4, 10):
... print extract_line("abc\ndefgh\ni", i)
abc
abc
abc
defgh
defgh
i
"""
p = text.rfind('\n', 0, index) + 1
q = text.find('\n', index)
if q < 0:
q = len(text)
return text[p:q]
class SuspiciousVisitor(nodes.GenericNodeVisitor):
lastlineno = 0
def __init__(self, document, builder):
nodes.GenericNodeVisitor.__init__(self, document)
self.builder = builder
def default_visit(self, node):
if isinstance(node, (nodes.Text, nodes.image)): # direct text containers
text = node.astext()
# lineno seems to go backwards sometimes (?)
self.lastlineno = lineno = max(get_lineno(node) or 0, self.lastlineno)
seen = set() # don't report the same issue more than only once per line
for match in detect_all(text):
issue = match.group()
line = extract_line(text, match.start())
if (issue, line) not in seen:
self.builder.check_issue(line, lineno, issue)
seen.add((issue, line))
unknown_visit = default_visit
def visit_document(self, node):
self.lastlineno = 0
def visit_comment(self, node):
# ignore comments -- too much false positives.
# (although doing this could miss some errors;
# there were two sections "commented-out" by mistake
# in the Python docs that would not be catched)
raise nodes.SkipNode