import-checker: establish modern import convention
We introduce a new convention for declaring imports and enforce it via
the import checker script.
The new convention is only active when absolute imports are used, which is
currently nowhere. Keying off "from __future__ import absolute_import" to
engage the new import convention seems like the easiest solution. It is
also beneficial for Mercurial to use this mode because it means less work
and ambiguity for the importer and potentially better performance due to
fewer stat() system calls because the importer won't look for modules in
relative paths unless explicitly asked.
Once all files are converted to use absolute import, we can refactor
this code to again only have a single import convention and we can
require use of absolute import in the style checker.
The rules for the new convention are documented in the docstring of the
added function. Tests have been added to test-module-imports.t. Some
tests are sensitive to newlines and source column position, which makes
docstring testing difficult and/or impossible.
# minirst.py - minimal reStructuredText parser
#
# Copyright 2009, 2010 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
"""simplified reStructuredText parser.
This parser knows just enough about reStructuredText to parse the
Mercurial docstrings.
It cheats in a major way: nested blocks are not really nested. They
are just indented blocks that look like they are nested. This relies
on the user to keep the right indentation for the blocks.
Remember to update http://mercurial.selenic.com/wiki/HelpStyleGuide
when adding support for new constructs.
"""
import re
import util, encoding
from i18n import _
import cgi
def section(s):
return "%s\n%s\n\n" % (s, "\"" * encoding.colwidth(s))
def subsection(s):
return "%s\n%s\n\n" % (s, '=' * encoding.colwidth(s))
def subsubsection(s):
return "%s\n%s\n\n" % (s, "-" * encoding.colwidth(s))
def subsubsubsection(s):
return "%s\n%s\n\n" % (s, "." * encoding.colwidth(s))
def replace(text, substs):
'''
Apply a list of (find, replace) pairs to a text.
>>> replace("foo bar", [('f', 'F'), ('b', 'B')])
'Foo Bar'
>>> encoding.encoding = 'latin1'
>>> replace('\\x81\\\\', [('\\\\', '/')])
'\\x81/'
>>> encoding.encoding = 'shiftjis'
>>> replace('\\x81\\\\', [('\\\\', '/')])
'\\x81\\\\'
'''
# some character encodings (cp932 for Japanese, at least) use
# ASCII characters other than control/alphabet/digit as a part of
# multi-bytes characters, so direct replacing with such characters
# on strings in local encoding causes invalid byte sequences.
utext = text.decode(encoding.encoding)
for f, t in substs:
utext = utext.replace(f.decode("ascii"), t.decode("ascii"))
return utext.encode(encoding.encoding)
_blockre = re.compile(r"\n(?:\s*\n)+")
def findblocks(text):
"""Find continuous blocks of lines in text.
Returns a list of dictionaries representing the blocks. Each block
has an 'indent' field and a 'lines' field.
"""
blocks = []
for b in _blockre.split(text.lstrip('\n').rstrip()):
lines = b.splitlines()
if lines:
indent = min((len(l) - len(l.lstrip())) for l in lines)
lines = [l[indent:] for l in lines]
blocks.append({'indent': indent, 'lines': lines})
return blocks
def findliteralblocks(blocks):
"""Finds literal blocks and adds a 'type' field to the blocks.
Literal blocks are given the type 'literal', all other blocks are
given type the 'paragraph'.
"""
i = 0
while i < len(blocks):
# Searching for a block that looks like this:
#
# +------------------------------+
# | paragraph |
# | (ends with "::") |
# +------------------------------+
# +---------------------------+
# | indented literal block |
# +---------------------------+
blocks[i]['type'] = 'paragraph'
if blocks[i]['lines'][-1].endswith('::') and i + 1 < len(blocks):
indent = blocks[i]['indent']
adjustment = blocks[i + 1]['indent'] - indent
if blocks[i]['lines'] == ['::']:
# Expanded form: remove block
del blocks[i]
i -= 1
elif blocks[i]['lines'][-1].endswith(' ::'):
# Partially minimized form: remove space and both
# colons.
blocks[i]['lines'][-1] = blocks[i]['lines'][-1][:-3]
elif len(blocks[i]['lines']) == 1 and \
blocks[i]['lines'][0].lstrip(' ').startswith('.. ') and \
blocks[i]['lines'][0].find(' ', 3) == -1:
# directive on its own line, not a literal block
i += 1
continue
else:
# Fully minimized form: remove just one colon.
blocks[i]['lines'][-1] = blocks[i]['lines'][-1][:-1]
# List items are formatted with a hanging indent. We must
# correct for this here while we still have the original
# information on the indentation of the subsequent literal
# blocks available.
m = _bulletre.match(blocks[i]['lines'][0])
if m:
indent += m.end()
adjustment -= m.end()
# Mark the following indented blocks.
while i + 1 < len(blocks) and blocks[i + 1]['indent'] > indent:
blocks[i + 1]['type'] = 'literal'
blocks[i + 1]['indent'] -= adjustment
i += 1
i += 1
return blocks
_bulletre = re.compile(r'(-|[0-9A-Za-z]+\.|\(?[0-9A-Za-z]+\)|\|) ')
_optionre = re.compile(r'^(-([a-zA-Z0-9]), )?(--[a-z0-9-]+)'
r'((.*) +)(.*)$')
_fieldre = re.compile(r':(?![: ])([^:]*)(?<! ):[ ]+(.*)')
_definitionre = re.compile(r'[^ ]')
_tablere = re.compile(r'(=+\s+)*=+')
def splitparagraphs(blocks):
"""Split paragraphs into lists."""
# Tuples with (list type, item regexp, single line items?). Order
# matters: definition lists has the least specific regexp and must
# come last.
listtypes = [('bullet', _bulletre, True),
('option', _optionre, True),
('field', _fieldre, True),
('definition', _definitionre, False)]
def match(lines, i, itemre, singleline):
"""Does itemre match an item at line i?
A list item can be followed by an indented line or another list
item (but only if singleline is True).
"""
line1 = lines[i]
line2 = i + 1 < len(lines) and lines[i + 1] or ''
if not itemre.match(line1):
return False
if singleline:
return line2 == '' or line2[0] == ' ' or itemre.match(line2)
else:
return line2.startswith(' ')
i = 0
while i < len(blocks):
if blocks[i]['type'] == 'paragraph':
lines = blocks[i]['lines']
for type, itemre, singleline in listtypes:
if match(lines, 0, itemre, singleline):
items = []
for j, line in enumerate(lines):
if match(lines, j, itemre, singleline):
items.append({'type': type, 'lines': [],
'indent': blocks[i]['indent']})
items[-1]['lines'].append(line)
blocks[i:i + 1] = items
break
i += 1
return blocks
_fieldwidth = 14
def updatefieldlists(blocks):
"""Find key for field lists."""
i = 0
while i < len(blocks):
if blocks[i]['type'] != 'field':
i += 1
continue
j = i
while j < len(blocks) and blocks[j]['type'] == 'field':
m = _fieldre.match(blocks[j]['lines'][0])
key, rest = m.groups()
blocks[j]['lines'][0] = rest
blocks[j]['key'] = key
j += 1
i = j + 1
return blocks
def updateoptionlists(blocks):
i = 0
while i < len(blocks):
if blocks[i]['type'] != 'option':
i += 1
continue
optstrwidth = 0
j = i
while j < len(blocks) and blocks[j]['type'] == 'option':
m = _optionre.match(blocks[j]['lines'][0])
shortoption = m.group(2)
group3 = m.group(3)
longoption = group3[2:].strip()
desc = m.group(6).strip()
longoptionarg = m.group(5).strip()
blocks[j]['lines'][0] = desc
noshortop = ''
if not shortoption:
noshortop = ' '
opt = "%s%s" % (shortoption and "-%s " % shortoption or '',
("%s--%s %s") % (noshortop, longoption,
longoptionarg))
opt = opt.rstrip()
blocks[j]['optstr'] = opt
optstrwidth = max(optstrwidth, encoding.colwidth(opt))
j += 1
for block in blocks[i:j]:
block['optstrwidth'] = optstrwidth
i = j + 1
return blocks
def prunecontainers(blocks, keep):
"""Prune unwanted containers.
The blocks must have a 'type' field, i.e., they should have been
run through findliteralblocks first.
"""
pruned = []
i = 0
while i + 1 < len(blocks):
# Searching for a block that looks like this:
#
# +-------+---------------------------+
# | ".. container ::" type |
# +---+ |
# | blocks |
# +-------------------------------+
if (blocks[i]['type'] == 'paragraph' and
blocks[i]['lines'][0].startswith('.. container::')):
indent = blocks[i]['indent']
adjustment = blocks[i + 1]['indent'] - indent
containertype = blocks[i]['lines'][0][15:]
prune = True
for c in keep:
if c in containertype.split('.'):
prune = False
if prune:
pruned.append(containertype)
# Always delete "..container:: type" block
del blocks[i]
j = i
i -= 1
while j < len(blocks) and blocks[j]['indent'] > indent:
if prune:
del blocks[j]
else:
blocks[j]['indent'] -= adjustment
j += 1
i += 1
return blocks, pruned
_sectionre = re.compile(r"""^([-=`:.'"~^_*+#])\1+$""")
def findtables(blocks):
'''Find simple tables
Only simple one-line table elements are supported
'''
for block in blocks:
# Searching for a block that looks like this:
#
# === ==== ===
# A B C
# === ==== === <- optional
# 1 2 3
# x y z
# === ==== ===
if (block['type'] == 'paragraph' and
len(block['lines']) > 2 and
_tablere.match(block['lines'][0]) and
block['lines'][0] == block['lines'][-1]):
block['type'] = 'table'
block['header'] = False
div = block['lines'][0]
# column markers are ASCII so we can calculate column
# position in bytes
columns = [x for x in xrange(len(div))
if div[x] == '=' and (x == 0 or div[x - 1] == ' ')]
rows = []
for l in block['lines'][1:-1]:
if l == div:
block['header'] = True
continue
row = []
# we measure columns not in bytes or characters but in
# colwidth which makes things tricky
pos = columns[0] # leading whitespace is bytes
for n, start in enumerate(columns):
if n + 1 < len(columns):
width = columns[n + 1] - start
v = encoding.getcols(l, pos, width) # gather columns
pos += len(v) # calculate byte position of end
row.append(v.strip())
else:
row.append(l[pos:].strip())
rows.append(row)
block['table'] = rows
return blocks
def findsections(blocks):
"""Finds sections.
The blocks must have a 'type' field, i.e., they should have been
run through findliteralblocks first.
"""
for block in blocks:
# Searching for a block that looks like this:
#
# +------------------------------+
# | Section title |
# | ------------- |
# +------------------------------+
if (block['type'] == 'paragraph' and
len(block['lines']) == 2 and
encoding.colwidth(block['lines'][0]) == len(block['lines'][1]) and
_sectionre.match(block['lines'][1])):
block['underline'] = block['lines'][1][0]
block['type'] = 'section'
del block['lines'][1]
return blocks
def inlineliterals(blocks):
substs = [('``', '"')]
for b in blocks:
if b['type'] in ('paragraph', 'section'):
b['lines'] = [replace(l, substs) for l in b['lines']]
return blocks
def hgrole(blocks):
substs = [(':hg:`', '"hg '), ('`', '"')]
for b in blocks:
if b['type'] in ('paragraph', 'section'):
# Turn :hg:`command` into "hg command". This also works
# when there is a line break in the command and relies on
# the fact that we have no stray back-quotes in the input
# (run the blocks through inlineliterals first).
b['lines'] = [replace(l, substs) for l in b['lines']]
return blocks
def addmargins(blocks):
"""Adds empty blocks for vertical spacing.
This groups bullets, options, and definitions together with no vertical
space between them, and adds an empty block between all other blocks.
"""
i = 1
while i < len(blocks):
if (blocks[i]['type'] == blocks[i - 1]['type'] and
blocks[i]['type'] in ('bullet', 'option', 'field')):
i += 1
elif not blocks[i - 1]['lines']:
# no lines in previous block, do not separate
i += 1
else:
blocks.insert(i, {'lines': [''], 'indent': 0, 'type': 'margin'})
i += 2
return blocks
def prunecomments(blocks):
"""Remove comments."""
i = 0
while i < len(blocks):
b = blocks[i]
if b['type'] == 'paragraph' and (b['lines'][0].startswith('.. ') or
b['lines'] == ['..']):
del blocks[i]
if i < len(blocks) and blocks[i]['type'] == 'margin':
del blocks[i]
else:
i += 1
return blocks
_admonitionre = re.compile(r"\.\. (admonition|attention|caution|danger|"
r"error|hint|important|note|tip|warning)::",
flags=re.IGNORECASE)
def findadmonitions(blocks):
"""
Makes the type of the block an admonition block if
the first line is an admonition directive
"""
i = 0
while i < len(blocks):
m = _admonitionre.match(blocks[i]['lines'][0])
if m:
blocks[i]['type'] = 'admonition'
admonitiontitle = blocks[i]['lines'][0][3:m.end() - 2].lower()
firstline = blocks[i]['lines'][0][m.end() + 1:]
if firstline:
blocks[i]['lines'].insert(1, ' ' + firstline)
blocks[i]['admonitiontitle'] = admonitiontitle
del blocks[i]['lines'][0]
i = i + 1
return blocks
_admonitiontitles = {'attention': _('Attention:'),
'caution': _('Caution:'),
'danger': _('!Danger!') ,
'error': _('Error:'),
'hint': _('Hint:'),
'important': _('Important:'),
'note': _('Note:'),
'tip': _('Tip:'),
'warning': _('Warning!')}
def formatoption(block, width):
desc = ' '.join(map(str.strip, block['lines']))
colwidth = encoding.colwidth(block['optstr'])
usablewidth = width - 1
hanging = block['optstrwidth']
initindent = '%s%s ' % (block['optstr'], ' ' * ((hanging - colwidth)))
hangindent = ' ' * (encoding.colwidth(initindent) + 1)
return ' %s\n' % (util.wrap(desc, usablewidth,
initindent=initindent,
hangindent=hangindent))
def formatblock(block, width):
"""Format a block according to width."""
if width <= 0:
width = 78
indent = ' ' * block['indent']
if block['type'] == 'admonition':
admonition = _admonitiontitles[block['admonitiontitle']]
if not block['lines']:
return indent + admonition + '\n'
hang = len(block['lines'][-1]) - len(block['lines'][-1].lstrip())
defindent = indent + hang * ' '
text = ' '.join(map(str.strip, block['lines']))
return '%s\n%s\n' % (indent + admonition,
util.wrap(text, width=width,
initindent=defindent,
hangindent=defindent))
if block['type'] == 'margin':
return '\n'
if block['type'] == 'literal':
indent += ' '
return indent + ('\n' + indent).join(block['lines']) + '\n'
if block['type'] == 'section':
underline = encoding.colwidth(block['lines'][0]) * block['underline']
return "%s%s\n%s%s\n" % (indent, block['lines'][0],indent, underline)
if block['type'] == 'table':
table = block['table']
# compute column widths
widths = [max([encoding.colwidth(e) for e in c]) for c in zip(*table)]
text = ''
span = sum(widths) + len(widths) - 1
indent = ' ' * block['indent']
hang = ' ' * (len(indent) + span - widths[-1])
for row in table:
l = []
for w, v in zip(widths, row):
pad = ' ' * (w - encoding.colwidth(v))
l.append(v + pad)
l = ' '.join(l)
l = util.wrap(l, width=width, initindent=indent, hangindent=hang)
if not text and block['header']:
text = l + '\n' + indent + '-' * (min(width, span)) + '\n'
else:
text += l + "\n"
return text
if block['type'] == 'definition':
term = indent + block['lines'][0]
hang = len(block['lines'][-1]) - len(block['lines'][-1].lstrip())
defindent = indent + hang * ' '
text = ' '.join(map(str.strip, block['lines'][1:]))
return '%s\n%s\n' % (term, util.wrap(text, width=width,
initindent=defindent,
hangindent=defindent))
subindent = indent
if block['type'] == 'bullet':
if block['lines'][0].startswith('| '):
# Remove bullet for line blocks and add no extra
# indention.
block['lines'][0] = block['lines'][0][2:]
else:
m = _bulletre.match(block['lines'][0])
subindent = indent + m.end() * ' '
elif block['type'] == 'field':
key = block['key']
subindent = indent + _fieldwidth * ' '
if len(key) + 2 > _fieldwidth:
# key too large, use full line width
key = key.ljust(width)
else:
# key fits within field width
key = key.ljust(_fieldwidth)
block['lines'][0] = key + block['lines'][0]
elif block['type'] == 'option':
return formatoption(block, width)
text = ' '.join(map(str.strip, block['lines']))
return util.wrap(text, width=width,
initindent=indent,
hangindent=subindent) + '\n'
def formathtml(blocks):
"""Format RST blocks as HTML"""
out = []
headernest = ''
listnest = []
def escape(s):
return cgi.escape(s, True)
def openlist(start, level):
if not listnest or listnest[-1][0] != start:
listnest.append((start, level))
out.append('<%s>\n' % start)
blocks = [b for b in blocks if b['type'] != 'margin']
for pos, b in enumerate(blocks):
btype = b['type']
level = b['indent']
lines = b['lines']
if btype == 'admonition':
admonition = escape(_admonitiontitles[b['admonitiontitle']])
text = escape(' '.join(map(str.strip, lines)))
out.append('<p>\n<b>%s</b> %s\n</p>\n' % (admonition, text))
elif btype == 'paragraph':
out.append('<p>\n%s\n</p>\n' % escape('\n'.join(lines)))
elif btype == 'margin':
pass
elif btype == 'literal':
out.append('<pre>\n%s\n</pre>\n' % escape('\n'.join(lines)))
elif btype == 'section':
i = b['underline']
if i not in headernest:
headernest += i
level = headernest.index(i) + 1
out.append('<h%d>%s</h%d>\n' % (level, escape(lines[0]), level))
elif btype == 'table':
table = b['table']
out.append('<table>\n')
for row in table:
out.append('<tr>')
for v in row:
out.append('<td>')
out.append(escape(v))
out.append('</td>')
out.append('\n')
out.pop()
out.append('</tr>\n')
out.append('</table>\n')
elif btype == 'definition':
openlist('dl', level)
term = escape(lines[0])
text = escape(' '.join(map(str.strip, lines[1:])))
out.append(' <dt>%s\n <dd>%s\n' % (term, text))
elif btype == 'bullet':
bullet, head = lines[0].split(' ', 1)
if bullet == '-':
openlist('ul', level)
else:
openlist('ol', level)
out.append(' <li> %s\n' % escape(' '.join([head] + lines[1:])))
elif btype == 'field':
openlist('dl', level)
key = escape(b['key'])
text = escape(' '.join(map(str.strip, lines)))
out.append(' <dt>%s\n <dd>%s\n' % (key, text))
elif btype == 'option':
openlist('dl', level)
opt = escape(b['optstr'])
desc = escape(' '.join(map(str.strip, lines)))
out.append(' <dt>%s\n <dd>%s\n' % (opt, desc))
# close lists if indent level of next block is lower
if listnest:
start, level = listnest[-1]
if pos == len(blocks) - 1:
out.append('</%s>\n' % start)
listnest.pop()
else:
nb = blocks[pos + 1]
ni = nb['indent']
if (ni < level or
(ni == level and
nb['type'] not in 'definition bullet field option')):
out.append('</%s>\n' % start)
listnest.pop()
return ''.join(out)
def parse(text, indent=0, keep=None):
"""Parse text into a list of blocks"""
pruned = []
blocks = findblocks(text)
for b in blocks:
b['indent'] += indent
blocks = findliteralblocks(blocks)
blocks = findtables(blocks)
blocks, pruned = prunecontainers(blocks, keep or [])
blocks = findsections(blocks)
blocks = inlineliterals(blocks)
blocks = hgrole(blocks)
blocks = splitparagraphs(blocks)
blocks = updatefieldlists(blocks)
blocks = updateoptionlists(blocks)
blocks = findadmonitions(blocks)
blocks = addmargins(blocks)
blocks = prunecomments(blocks)
return blocks, pruned
def formatblocks(blocks, width):
text = ''.join(formatblock(b, width) for b in blocks)
return text
def format(text, width=80, indent=0, keep=None, style='plain', section=None):
"""Parse and format the text according to width."""
blocks, pruned = parse(text, indent, keep or [])
if section:
sections = getsections(blocks)
blocks = []
i = 0
while i < len(sections):
name, nest, b = sections[i]
if name == section:
blocks.extend(b)
## Also show all subnested sections
while i + 1 < len(sections) and sections[i + 1][1] > nest:
i += 1
blocks.extend(sections[i][2])
i += 1
if style == 'html':
text = formathtml(blocks)
else:
text = ''.join(formatblock(b, width) for b in blocks)
if keep is None:
return text
else:
return text, pruned
def getsections(blocks):
'''return a list of (section name, nesting level, blocks) tuples'''
nest = ""
level = 0
secs = []
def getname(b):
x = b['lines'][0]
x = x.lower().strip('"')
if '(' in x:
x = x.split('(')[0]
return x
for b in blocks:
if b['type'] == 'section':
i = b['underline']
if i not in nest:
nest += i
level = nest.index(i) + 1
nest = nest[:level]
secs.append((getname(b), level, [b]))
elif b['type'] == 'definition':
i = ' '
if i not in nest:
nest += i
level = nest.index(i) + 1
nest = nest[:level]
secs.append((getname(b), level, [b]))
else:
if not secs:
# add an initial empty section
secs = [('', 0, [])]
secs[-1][2].append(b)
return secs
def decorateblocks(blocks, width):
'''generate a list of (section name, line text) pairs for search'''
lines = []
for s in getsections(blocks):
section = s[0]
text = formatblocks(s[2], width)
lines.append([(section, l) for l in text.splitlines(True)])
return lines
def maketable(data, indent=0, header=False):
'''Generate an RST table for the given table data as a list of lines'''
widths = [max(encoding.colwidth(e) for e in c) for c in zip(*data)]
indent = ' ' * indent
div = indent + ' '.join('=' * w for w in widths) + '\n'
out = [div]
for row in data:
l = []
for w, v in zip(widths, row):
if '\n' in v:
# only remove line breaks and indentation, long lines are
# handled by the next tool
v = ' '.join(e.lstrip() for e in v.split('\n'))
pad = ' ' * (w - encoding.colwidth(v))
l.append(v + pad)
out.append(indent + ' '.join(l) + "\n")
if header and len(data) > 1:
out.insert(2, div)
out.append(div)
return out