Mercurial > hg
view tests/test-run-tests.py @ 49000:dd6b67d5c256 stable
rust: fix unsound `OwningDirstateMap`
As per the previous patch, `OwningDirstateMap` is unsound. Self-referential
structs are difficult to implement correctly in Rust since the compiler is
free to move structs around as much as it wants to. They are also very rarely
needed in practice, so the state-of-the-art on how they should be done within
the Rust rules is still a bit new.
The crate `ouroboros` is an attempt at providing a safe way (in the Rust sense)
of declaring self-referential structs. It is getting a lot attention and was
improved very quickly when soundness issues were found in the past: rather than
relying on our own (limited) review circle, we might as well use the de-facto
common crate to fix this problem. This will give us a much better chance of
finding issues should any new ones be discovered as well as the benefit of
fewer `unsafe` APIs of our own.
I was starting to think about how I would present a safe API to the old struct
but soon realized that the callback-based approach was already done in
`ouroboros`, along with a lot more care towards refusing incorrect structs.
In short: we don't return a mutable reference to the `DirstateMap` anymore, we
expect users of its API to pass a `FnOnce` that takes the map as an argument.
This allows our `OwningDirstateMap` to control the input and output lifetimes
of the code that modifies it to prevent such issues.
Changing to `ouroboros` meant changing every API with it, but it is relatively
low churn in the end. It correctly identified the example buggy modification of
`copy_map_insert` outlined in the previous patch as violating the borrow rules.
Differential Revision: https://phab.mercurial-scm.org/D12429
author | Raphaël Gomès <rgomes@octobus.net> |
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date | Tue, 05 Apr 2022 10:55:28 +0200 |
parents | 75b623801f6a |
children | 6000f5b25c9b |
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"""test line matching with some failing examples and some which warn run-test.t only checks positive matches and can not see warnings (both by design) """ from __future__ import absolute_import, print_function import doctest import os import re # this is hack to make sure no escape characters are inserted into the output if 'TERM' in os.environ: del os.environ['TERM'] run_tests = __import__('run-tests') def prn(ex): m = ex.args[0] if isinstance(m, str): print(m) else: print(m.decode('utf-8')) def lm(expected, output): r"""check if output matches expected does it generally work? >>> lm(b'H*e (glob)\n', b'Here\n') True fail on bad test data >>> try: lm(b'a\n',b'a') ... except AssertionError as ex: print(ex) missing newline >>> try: lm(b'single backslash\n', b'single \backslash\n') ... except AssertionError as ex: prn(ex) single backslash or unknown char """ assert expected.endswith(b'\n') and output.endswith( b'\n' ), 'missing newline' assert not re.search( br'[^ \w\\/\r\n()*?]', expected + output ), b'single backslash or unknown char' test = run_tests.TTest(b'test-run-test.t', b'.', b'.') match, exact = test.linematch(expected, output) if isinstance(match, str): return 'special: ' + match elif isinstance(match, bytes): return 'special: ' + match.decode('utf-8') else: return bool(match) # do not return match object def wintests(): r"""test matching like running on windows enable windows matching on any os >>> _osaltsep = os.altsep >>> os.altsep = True >>> _osname = os.name >>> os.name = 'nt' >>> _old_windows = run_tests.WINDOWS >>> run_tests.WINDOWS = True valid match on windows >>> lm(b'g/a*/d (glob)\n', b'g\\abc/d\n') True direct matching, glob unnecessary >>> lm(b'g/b (glob)\n', b'g/b\n') 'special: -glob' missing glob >>> lm(b'/g/c/d/fg\n', b'\\g\\c\\d/fg\n') True >>> lm(b'/g/c/d/fg\n', b'\\g\\c\\d\\fg\r\n') True restore os.altsep >>> os.altsep = _osaltsep >>> os.name = _osname >>> run_tests.WINDOWS = _old_windows """ pass def otherostests(): r"""test matching like running on non-windows os disable windows matching on any os >>> _osaltsep = os.altsep >>> os.altsep = False >>> _osname = os.name >>> os.name = 'nt' backslash does not match slash >>> lm(b'h/a* (glob)\n', b'h\\ab\n') False direct matching glob can not be recognized >>> lm(b'h/b (glob)\n', b'h/b\n') True missing glob can not not be recognized >>> lm(b'/h/c/df/g/\n', b'\\h/c\\df/g\\\n') False restore os.altsep >>> os.altsep = _osaltsep >>> os.name = _osname """ pass if __name__ == '__main__': doctest.testmod()