procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
# config.py - configuration parsing for Mercurial
#
# Copyright 2009 Olivia Mackall <olivia@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.
import errno
import os
from .i18n import _
from .pycompat import getattr
from . import (
encoding,
error,
util,
)
class config:
def __init__(self, data=None):
self._current_source_level = 0
self._data = {}
self._unset = []
if data:
for k in data._data:
self._data[k] = data[k].copy()
self._current_source_level = data._current_source_level + 1
def new_source(self):
"""increment the source counter
This is used to define source priority when reading"""
self._current_source_level += 1
def copy(self):
return config(self)
def __contains__(self, section):
return section in self._data
def hasitem(self, section, item):
return item in self._data.get(section, {})
def __getitem__(self, section):
return self._data.get(section, {})
def __iter__(self):
for d in self.sections():
yield d
def update(self, src):
current_level = self._current_source_level
current_level += 1
max_level = self._current_source_level
for s, n in src._unset:
ds = self._data.get(s, None)
if ds is not None and n in ds:
self._data[s] = ds.preparewrite()
del self._data[s][n]
for s in src:
ds = self._data.get(s, None)
if ds:
self._data[s] = ds.preparewrite()
else:
self._data[s] = util.cowsortdict()
for k, v in src._data[s].items():
value, source, level = v
level += current_level
max_level = max(level, current_level)
self._data[s][k] = (value, source, level)
self._current_source_level = max_level
def _get(self, section, item):
return self._data.get(section, {}).get(item)
def get(self, section, item, default=None):
result = self._get(section, item)
if result is None:
return default
return result[0]
def backup(self, section, key):
"""return a tuple allowing restore to reinstall a previous value
The main reason we need it is because it handles the "no data" case.
"""
try:
item = self._data[section][key]
except KeyError:
return (section, key)
else:
return (section, key) + item
def source(self, section, item):
result = self._get(section, item)
if result is None:
return b""
return result[1]
def level(self, section, item):
result = self._get(section, item)
if result is None:
return None
return result[2]
def sections(self):
return sorted(self._data.keys())
def items(self, section):
items = self._data.get(section, {}).items()
return [(k, v[0]) for (k, v) in items]
def set(self, section, item, value, source=b""):
assert not isinstance(
section, str
), b'config section may not be unicode strings on Python 3'
assert not isinstance(
item, str
), b'config item may not be unicode strings on Python 3'
assert not isinstance(
value, str
), b'config values may not be unicode strings on Python 3'
if section not in self:
self._data[section] = util.cowsortdict()
else:
self._data[section] = self._data[section].preparewrite()
self._data[section][item] = (value, source, self._current_source_level)
def alter(self, section, key, new_value):
"""alter a value without altering its source or level
This method is meant to be used by `ui.fixconfig` only."""
item = self._data[section][key]
size = len(item)
new_item = (new_value,) + item[1:]
assert len(new_item) == size
self._data[section][key] = new_item
def restore(self, data):
"""restore data returned by self.backup"""
if len(data) != 2:
# restore old data
section, key = data[:2]
item = data[2:]
self._data[section] = self._data[section].preparewrite()
self._data[section][key] = item
else:
# no data before, remove everything
section, item = data
if section in self._data:
self._data[section].pop(item, None)
def parse(self, src, data, sections=None, remap=None, include=None):
sectionre = util.re.compile(br'\[([^\[]+)\]')
itemre = util.re.compile(br'([^=\s][^=]*?)\s*=\s*(.*\S|)')
contre = util.re.compile(br'\s+(\S|\S.*\S)\s*$')
emptyre = util.re.compile(br'(;|#|\s*$)')
commentre = util.re.compile(br'(;|#)')
unsetre = util.re.compile(br'%unset\s+(\S+)')
includere = util.re.compile(br'%include\s+(\S|\S.*\S)\s*$')
section = b""
item = None
line = 0
cont = False
if remap:
section = remap.get(section, section)
for l in data.splitlines(True):
line += 1
if line == 1 and l.startswith(b'\xef\xbb\xbf'):
# Someone set us up the BOM
l = l[3:]
if cont:
if commentre.match(l):
continue
m = contre.match(l)
if m:
if sections and section not in sections:
continue
v = self.get(section, item) + b"\n" + m.group(1)
self.set(section, item, v, b"%s:%d" % (src, line))
continue
item = None
cont = False
m = includere.match(l)
if m and include:
expanded = util.expandpath(m.group(1))
try:
include(expanded, remap=remap, sections=sections)
except IOError as inst:
if inst.errno != errno.ENOENT:
raise error.ConfigError(
_(b"cannot include %s (%s)")
% (expanded, encoding.strtolocal(inst.strerror)),
b"%s:%d" % (src, line),
)
continue
if emptyre.match(l):
continue
m = sectionre.match(l)
if m:
section = m.group(1)
if remap:
section = remap.get(section, section)
if section not in self:
self._data[section] = util.cowsortdict()
continue
m = itemre.match(l)
if m:
item = m.group(1)
cont = True
if sections and section not in sections:
continue
self.set(section, item, m.group(2), b"%s:%d" % (src, line))
continue
m = unsetre.match(l)
if m:
name = m.group(1)
if sections and section not in sections:
continue
if self.get(section, name) is not None:
self._data[section] = self._data[section].preparewrite()
del self._data[section][name]
self._unset.append((section, name))
continue
message = l.rstrip()
if l.startswith(b' '):
message = b"unexpected leading whitespace: %s" % message
raise error.ConfigError(message, (b"%s:%d" % (src, line)))
def read(self, path, fp=None, sections=None, remap=None):
self.new_source()
if not fp:
fp = util.posixfile(path, b'rb')
assert (
getattr(fp, 'mode', 'rb') == 'rb'
), b'config files must be opened in binary mode, got fp=%r mode=%r' % (
fp,
fp.mode,
)
dir = os.path.dirname(path)
def include(rel, remap, sections):
abs = os.path.normpath(os.path.join(dir, rel))
self.read(abs, remap=remap, sections=sections)
# anything after the include has a higher level
self.new_source()
self.parse(
path, fp.read(), sections=sections, remap=remap, include=include
)