When `allow_abbrev` was first added, disabling the abbreviation of
long options broke the grouping of short flags ([bpo-26967](https://bugs.python.org/issue26967)). As a fix,
b1e4d1b603 (contained in v3.8) ignores `allow_abbrev=False` for a
given argument string if the string does _not_ start with "--"
(i.e. it doesn't look like a long option).
This fix, however, doesn't take into account that long options can
start with alternative characters specified via `prefix_chars`,
introducing a regression: `allow_abbrev=False` has no effect on long
options that start with an alternative prefix character.
The most minimal fix would be to replace the "starts with --" check
with a "starts with two prefix_chars characters". But
`_get_option_tuples` already distinguishes between long and short
options, so let's instead piggyback off of that check by moving the
`allow_abbrev` condition into `_get_option_tuples`.
https://bugs.python.org/issue39546
The GNU docs describe the `devmajor` and `devminor` fields of the tar
header struct only in the context of character and block special files,
suggesting that in other cases they are not populated. Typical utilities
behave accordingly; this patch teaches `tarfile` to do the same.
Improve multi-threaded performance by dropping the GIL in the fast path
of bytes.join. To avoid increasing overhead for small joins, it is only
done if the output size exceeds a threshold.
* Reorder the __aenter__ and __aexit__ checks for async with
* Add assertions for async with body being skipped
* Swap __aexit__ and __aenter__ loading in the documentation
The importlib.metadata documentation uses hardcoded links to internal
pages. This results in minor rendering issues. This change replaces
the hardcoded links with suitable Sphinx roles.
Signed-off-by: Oleg Höfling <oleg.hoefling@gmail.com>
On most platforms, the `environ` symbol is accessible everywhere.
In a dylib on OSX, it's not easily accessible, you need to find it with
_NSGetEnviron.
The code was caching the *value* of environ. But a setenv() can change the value,
leaving garbage at the old value. Fix: don't cache the value of environ, just
read it every time.
The regex http.cookiejar.LOOSE_HTTP_DATE_RE was vulnerable to regular
expression denial of service (REDoS).
LOOSE_HTTP_DATE_RE.match is called when using http.cookiejar.CookieJar
to parse Set-Cookie headers returned by a server.
Processing a response from a malicious HTTP server can lead to extreme
CPU usage and execution will be blocked for a long time.
The regex contained multiple overlapping \s* capture groups.
Ignoring the ?-optional capture groups the regex could be simplified to
\d+-\w+-\d+(\s*\s*\s*)$
Therefore, a long sequence of spaces can trigger bad performance.
Matching a malicious string such as
LOOSE_HTTP_DATE_RE.match("1-c-1" + (" " * 2000) + "!")
caused catastrophic backtracking.
The fix removes ambiguity about which \s* should match a particular
space.
You can create a malicious server which responds with Set-Cookie headers
to attack all python programs which access it e.g.
from http.server import BaseHTTPRequestHandler, HTTPServer
def make_set_cookie_value(n_spaces):
spaces = " " * n_spaces
expiry = f"1-c-1{spaces}!"
return f"b;Expires={expiry}"
class Handler(BaseHTTPRequestHandler):
def do_GET(self):
self.log_request(204)
self.send_response_only(204) # Don't bother sending Server and Date
n_spaces = (
int(self.path[1:]) # Can GET e.g. /100 to test shorter sequences
if len(self.path) > 1 else
65506 # Max header line length 65536
)
value = make_set_cookie_value(n_spaces)
for i in range(99): # Not necessary, but we can have up to 100 header lines
self.send_header("Set-Cookie", value)
self.end_headers()
if __name__ == "__main__":
HTTPServer(("", 44020), Handler).serve_forever()
This server returns 99 Set-Cookie headers. Each has 65506 spaces.
Extracting the cookies will pretty much never complete.
Vulnerable client using the example at the bottom of
https://docs.python.org/3/library/http.cookiejar.html :
import http.cookiejar, urllib.request
cj = http.cookiejar.CookieJar()
opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))
r = opener.open("http://localhost:44020/")
The popular requests library was also vulnerable without any additional
options (as it uses http.cookiejar by default):
import requests
requests.get("http://localhost:44020/")
* Regression test for http.cookiejar REDoS
If we regress, this test will take a very long time.
* Improve performance of http.cookiejar.ISO_DATE_RE
A string like
"444444" + (" " * 2000) + "A"
could cause poor performance due to the 2 overlapping \s* groups,
although this is not as serious as the REDoS in LOOSE_HTTP_DATE_RE was.
* Flip equality to use mock calls' __eq__
* bpo-37555: Regression test demonstrating assert_has_calls not working with ANY and spec_set
Co-authored-by: Neal Finne <neal@nealfinne.com>
* Revert "Flip equality to use mock calls' __eq__"
This reverts commit 94ddf54c5a.
* bpo-37555: Add regression tests for mock ANY ordering issues
Add regression tests for whether __eq__ is order agnostic on _Call and _CallList, which is useful for comparisons involving ANY, especially if the ANY comparison is to a class not defaulting __eq__ to NotImplemented.
Co-authored-by: Neal Finne <neal@nealfinne.com>
* bpo-37555: Fix _CallList and _Call order sensitivity
_Call and _CallList depend on ordering to correctly process that an object being compared to ANY with __eq__ should return True. This fix updates the comparison to check both a == b and b == a and return True if either condition is met, fixing situations from the tests in the previous two commits where assertEqual would not be commutative if checking _Call or _CallList objects. This seems like a reasonable fix considering that the Python data model specifies that if an object doesn't know how to compare itself to another object it should return NotImplemented, and that on getting NotImplemented from a == b, it should try b == a, implying that good behavior for __eq__ is commutative. This also flips the order of comparison in _CallList's __contains__ method, guaranteeing ANY will be on the left and have it's __eq__ called for equality checking, fixing the interaction between assert_has_calls and ANY.
Co-author: Neal Finne <neal@neal.finne.com>
* bpo-37555: Ensure _call_matcher returns _Call object
* Adding ACK and news entry
* bpo-37555: Replacing __eq__ with == to sidestep NotImplemented
bool(NotImplemented) returns True, so it's necessary to use ==
instead of __eq__ in this comparison.
* bpo-37555: cleaning up changes unnecessary to the final product
* bpo-37555: Fixed call on bound arguments to respect args and kwargs
* Revert "bpo-37555: Add regression tests for mock ANY ordering issues"
This reverts commit 49c5310ad4.
* Revert "bpo-37555: cleaning up changes unnecessary to the final product"
This reverts commit 18e964ba01.
* Revert "bpo-37555: Replacing __eq__ with == to sidestep NotImplemented"
This reverts commit f295eaca5b.
* Revert "bpo-37555: Fix _CallList and _Call order sensitivity"
This reverts commit 874fb697b8.
* Updated NEWS.d
* bpo-37555: Add tests checking every function using _call_matcher both with and without spec
* bpo-37555: Ensure all assert methods using _call_matcher are actually passing calls
* Remove AnyCompare and use call objects everywhere.
* Revert "Remove AnyCompare and use call objects everywhere."
This reverts commit 24973c0b32.
* Check for exception in assert_any_await
Relative imports use resolve_name to get the absolute target name,
which first seeks the current module's absolute package name from the globals:
If __package__ (and __spec__.parent) are missing then
import uses __name__, truncating the last segment if
the module is a submodule rather than a package __init__.py
(which it guesses from whether __path__ is defined).
The __name__ attempt should fail if there is no parent package (top level modules),
if __name__ is '__main__' (-m entry points), or both (scripts).
That is, if both __name__ has no subcomponents and the module does not seem
to be a package __init__ module then import should fail.
Fixes a case in which email._header_value_parser.get_unstructured hangs the system for some invalid headers. This covers the cases in which the header contains either:
- a case without trailing whitespace
- an invalid encoded word
https://bugs.python.org/issue37764
This fix should also be backported to 3.7 and 3.8
https://bugs.python.org/issue37764
FreeBSD implementation of poll(2) restricts the timeout argument to be
either zero, or positive, or equal to INFTIM (-1).
Unless otherwise overridden, socket timeout defaults to -1. This value
is then converted to milliseconds (-1000) and used as argument to the
poll syscall. poll returns EINVAL (22), and the connection fails.
This bug was discovered during the EINTR handling testing, and the
reproduction code can be found in
https://bugs.python.org/issue23618 (see connect_eintr.py,
attached). On GNU/Linux, the example runs as expected.
This change is trivial:
If the supplied timeout value is negative, truncate it to -1.
This fixes an inconsistency between the Python and C implementations of
the datetime module. The pure python version of the code was not
accepting offsets greater than 23:59 but less than 24:00. This is an
accidental legacy of the original implementation, which was put in place
before tzinfo allowed sub-minute time zone offsets.
GH-14878
BPO -16970: Adding error message for invalid args
Applied the patch argparse-v2 patch issue 16970, ran patch check and the test suite, test_argparse with 0 errors
https://bugs.python.org/issue16970
Expose the CAN_BCM SocketCAN constants used in the bcm_msg_head struct
flags (provided by <linux/can/bcm.h>) under the socket library.
This adds the following constants with a CAN_BCM prefix:
* SETTIMER
* STARTTIMER
* TX_COUNTEVT
* TX_ANNOUNCE
* TX_CP_CAN_ID
* RX_FILTER_ID
* RX_CHECK_DLC
* RX_NO_AUTOTIMER
* RX_ANNOUNCE_RESUME
* TX_RESET_MULTI_IDX
* RX_RTR_FRAME
* CAN_FD_FRAME
The CAN_FD_FRAME flag was introduced in the 4.8 kernel, while the other
ones were present since SocketCAN drivers were mainlined in 2.6.25. As
such, it is probably unnecessary to guard against these constants being
missing.
The `allow_abbrev` option for ArgumentParser is documented and intended to disable support for unique prefixes of --options, which may sometimes be ambiguous due to deferred parsing.
However, the initial implementation also broke parsing of grouped short flags, such as `-ab` meaning `-a -b` (or `-a=b`). Checking the argument for a leading `--` before rejecting it fixes this.
This was prompted by pytest-dev/pytest#5469, so a backport to at least 3.8 would be great 😄
And this is my first PR to CPython, so please let me know if I've missed anything!
https://bugs.python.org/issue26967
Hi,
I've faced an issue w/ `mailbox.Maildir()`. The case is following:
1. I create a folder with `tempfile.TemporaryDirectory()`, so it's empty
2. I pass that folder path as an argument when instantiating `mailbox.Maildir()`
3. Then I receive an exception happening because "there's no such file or directory" (namely `cur`, `tmp` or `new`) during interaction with Maildir
**Expected result:** subdirs are created during `Maildir()` instance creation.
**Actual result:** subdirs are assumed as existing which leads to exceptions during use.
**Workaround:** remove the actual dir before passing the path to `Maildir()`. It will be created automatically with all subdirs needed.
**Fix:** This PR. Basically it adds creation of subdirs regardless of whether the base dir existed before.
https://bugs.python.org/issue30088
Nested BinOp instances (e.g. a+b+c) had a wrong col_offset for the
second BinOp (e.g. 2 instead of 0 in the example). Fix it by using the
correct st node to copy the line and col_offset from in ast.c.
Replacing the deprecated method "random.choose" to "random.choice" was technically not part of the original issue. However, it was discussed in the talk page and involved one of the files being moved. I assumed this was too minor to justify the creation of a separate issue.
Also, I added my name to the contributors list in Misc/ACKS. This will be my third PR to cpython, forgot to do it in the previous ones.
https://bugs.python.org/issue19696
* bpo-37014: Update docstring and Documentation of fileinput.FileInput()
* Explain the behavior of fileinput.FileInput() when reading stdin.
* Update blurb.
* bpo-37014: Fix typo in the docstring and documentation.
GH-13238 made extra text after a # type: ignore accepted by the parser.
This finishes the job and actually plumbs the extra text through the
parser and makes it available in the AST.
In order to support typing checks calling hex(), oct() and bin() on user-defined classes, a SupportIndex protocol is required. The ability to check these at runtime would be good to add for completeness sake. This is pretty much just a copy of SupportsInt with the names tweaked.