chore(deps): update rust crate regex to 1.9.5

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
regex	dev-dependencies	minor	1.7.1 -> 1.9.5

---

Release Notes

rust-lang/regex (regex)

v1.9.5

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==================
This is a patch release that hopefully mostly fixes a performance bug that
occurs when sharing a regex across multiple threads.

Issue #​934
explains this in more detail. It is also noted in the crate
documentation.
The bug can appear when sharing a regex across multiple threads simultaneously,
as might be the case when using a regex from a OnceLock, lazy_static or
similar primitive. Usually high contention only results when using many threads
to execute searches on small haystacks.

One can avoid the contention problem entirely through one of two methods.
The first is to use lower level APIs from regex-automata that require passing
state explicitly, such as meta::Regex::search_with.
The second is to clone a regex and send it to other threads explicitly. This
will not use any additional memory usage compared to sharing the regex. The
only downside of this approach is that it may be less convenient, for example,
it won't work with things like OnceLock or lazy_static or once_cell.

With that said, as of this release, the contention performance problems have
been greatly reduced. This was achieved by changing the free-list so that it
was sharded across threads, and that ensuring each sharded mutex occupies a
single cache line to mitigate false sharing. So while contention may still
impact performance in some cases, it should be a lot better now.

Because of the changes to how the free-list works, please report any issues you
find with this release. That not only includes search time regressions but also
significant regressions in memory usage. Reporting improvements is also welcome
as well! If possible, provide a reproduction.

Bug fixes:

• BUG #​934:
  Fix a performance bug where high contention on a single regex led to massive
  slow downs.

v1.9.4

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==================
This is a patch release that fixes a bug where RegexSet::is_match(..) could
incorrectly return false (even when RegexSet::matches(..).matched_any()
returns true).

Bug fixes:

• BUG #​1070:
  Fix a bug where a prefilter was incorrectly configured for a RegexSet.

v1.9.3

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==================
This is a patch release that fixes a bug where some searches could result in
incorrect match offsets being reported. It is difficult to characterize the
types of regexes susceptible to this bug. They generally involve patterns
that contain no prefix or suffix literals, but have an inner literal along with
a regex prefix that can conditionally match.

Bug fixes:

• BUG #​1060:
  Fix a bug with the reverse inner literal optimization reporting incorrect match
  offsets.

v1.9.2

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==================
This is a patch release that fixes another memory usage regression. This
particular regression occurred only when using a RegexSet. In some cases,
much more heap memory (by one or two orders of magnitude) was allocated than in
versions prior to 1.9.0.

Bug fixes:

• BUG #​1059:
  Fix a memory usage regression when using a RegexSet.

v1.9.1

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==================
This is a patch release which fixes a memory usage regression. In the regex
1.9 release, one of the internal engines used a more aggressive allocation
strategy than what was done previously. This patch release reverts to the
prior on-demand strategy.

Bug fixes:

• BUG #​1027:
  Change the allocation strategy for the backtracker to be less aggressive.

v1.9.0

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==================
This release marks the end of a years long rewrite of the regex crate
internals. Since this is
such a big release, please report any issues or regressions you find. We would
also love to hear about improvements as well.

In addition to many internal improvements that should hopefully result in
"my regex searches are faster," there have also been a few API additions:

• A new Captures::extract method for quickly accessing the substrings
  that match each capture group in a regex.
• A new inline flag, R, which enables CRLF mode. This makes . match any
  Unicode scalar value except for \r and \n, and also makes (?m:^) and
  (?m:$) match after and before both \r and \n, respectively, but never
  between a \r and \n.
• RegexBuilder::line_terminator was added to further customize the line
  terminator used by (?m:^) and (?m:$) to be any arbitrary byte.
• The std Cargo feature is now actually optional. That is, the regex crate
  can be used without the standard library.
• Because regex 1.9 may make binary size and compile times even worse, a
  new experimental crate called regex-lite has been published. It prioritizes
  binary size and compile times over functionality (like Unicode) and
  performance. It shares no code with the regex crate.

New features:

• FEATURE #​244:
  One can opt into CRLF mode via the R flag.
  e.g., (?mR:$) matches just before \r\n.
• FEATURE #​259:
  Multi-pattern searches with offsets can be done with regex-automata 0.3.
• FEATURE #​476:
  std is now an optional feature. regex may be used with only alloc.
• FEATURE #​644:
  RegexBuilder::line_terminator configures how (?m:^) and (?m:$) behave.
• FEATURE #​675:
  Anchored search APIs are now available in regex-automata 0.3.
• FEATURE #​824:
  Add new Captures::extract method for easier capture group access.
• FEATURE #​961:
  Add regex-lite crate with smaller binary sizes and faster compile times.
• FEATURE #​1022:
  Add TryFrom implementations for the Regex type.

Performance improvements:

• PERF #​68:
  Added a one-pass DFA engine for faster capture group matching.
• PERF #​510:
  Inner literals are now used to accelerate searches, e.g., \w+@​\w+ will scan
  for @.
• PERF #​787,
  PERF #​891:
  Makes literal optimizations apply to regexes of the form \b(foo|bar|quux)\b.

(There are many more performance improvements as well, but not all of them have
specific issues devoted to them.)

Bug fixes:

• BUG #​429:
  Fix matching bugs related to \B and inconsistencies across internal engines.
• BUG #​517:
  Fix matching bug with capture groups.
• BUG #​579:
  Fix matching bug with word boundaries.
• BUG #​779:
  Fix bug where some regexes like (re)+ were not equivalent to (re)(re)*.
• BUG #​850:
  Fix matching bug inconsistency between NFA and DFA engines.
• BUG #​921:
  Fix matching bug where literal extraction got confused by $.
• BUG #​976:
  Add documentation to replacement routines about dealing with fallibility.
• BUG #​1002:
  Use corpus rejection in fuzz testing.

v1.8.4

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==================
This is a patch release that fixes a bug where (?-u:\B) was allowed in
Unicode regexes, despite the fact that the current matching engines can report
match offsets between the code units of a single UTF-8 encoded codepoint. That
in turn means that match offsets that split a codepoint could be reported,
which in turn results in panicking when one uses them to slice a &str.

This bug occurred in the transition to regex 1.8 because the underlying
syntactical error that prevented this regex from compiling was intentionally
removed. That's because (?-u:\B) will be permitted in Unicode regexes in
regex 1.9, but the matching engines will guarantee to never report match
offsets that split a codepoint. When the underlying syntactical error was
removed, no code was added to ensure that (?-u:\B) didn't compile in the
regex 1.8 transition release. This release, regex 1.8.4, adds that code
such that Regex::new(r"(?-u:\B)") returns to the regex <1.8 behavior of
not compiling. (A bytes::Regex can still of course compile it.)

Bug fixes:

• BUG #​1006:
  Fix a bug where (?-u:\B) was allowed in Unicode regexes, and in turn could
  lead to match offsets that split a codepoint in &str.

v1.8.3

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==================
This is a patch release that fixes a bug where the regex would report a
match at every position even when it shouldn't. This could occur in a very
small subset of regexes, usually an alternation of simple literals that
have particular properties. (See the issue linked below for a more precise
description.)

Bug fixes:

• BUG #​999:
  Fix a bug where a match at every position is erroneously reported.

v1.8.2

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==================
This is a patch release that fixes a bug where regex compilation could panic
in debug mode for regexes with large counted repetitions. For example,
a{2147483516}{2147483416}{5} resulted in an integer overflow that wrapped
in release mode but panicking in debug mode. Despite the unintended wrapping
arithmetic in release mode, it didn't cause any other logical bugs since the
errant code was for new analysis that wasn't used yet.

Bug fixes:

• BUG #​995:
  Fix a bug where regex compilation with large counted repetitions could panic.

v1.8.1

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==================
This is a patch release that fixes a bug where a regex match could be reported
where none was found. Specifically, the bug occurs when a pattern contains some
literal prefixes that could be extracted and an optional word boundary in the
prefix.

Bug fixes:

• BUG #​981:
  Fix a bug where a word boundary could interact with prefix literal
  optimizations and lead to a false positive match.

v1.8.0

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==================
This is a sizeable release that will be soon followed by another sizeable
release. Both of them will combined close over 40 existing issues and PRs.

This first release, despite its size, essentially represents preparatory work
for the second release, which will be even bigger. Namely, this release:

• Increases the MSRV to Rust 1.60.0, which was released about 1 year ago.
• Upgrades its dependency on aho-corasick to the recently released 1.0
  version.
• Upgrades its dependency on regex-syntax to the simultaneously released
  0.7 version. The changes to regex-syntax principally revolve around a
  rewrite of its literal extraction code and a number of simplifications and
  optimizations to its high-level intermediate representation (HIR).

The second release, which will follow ~shortly after the release above, will
contain a soup-to-nuts rewrite of every regex engine. This will be done by
bringing regex-automata into
this repository, and then changing the regex crate to be nothing but an API
shim layer on top of regex-automata's API.

These tandem releases are the culmination of about 3
years of on-and-off work that began in earnest in March
2020.

Because of the scale of changes involved in these releases, I would love to
hear about your experience. Especially if you notice undocumented changes in
behavior or performance changes (positive or negative).

Most changes in the first release are listed below. For more details, please
see the commit log, which reflects a linear and decently documented history
of all changes.

New features:

• FEATURE #​501:
  Permit many more characters to be escaped, even if they have no significance.
  More specifically, any ASCII character except for [0-9A-Za-z<>] can now be
  escaped. Also, a new routine, is_escapeable_character, has been added to
  regex-syntax to query whether a character is escapeable or not.
• FEATURE #​547:
  Add Regex::captures_at. This fills a hole in the API, but doesn't otherwise
  introduce any new expressive power.
• FEATURE #​595:
  Capture group names are now Unicode-aware. They can now begin with either a _
  or any "alphabetic" codepoint. After the first codepoint, subsequent codepoints
  can be any sequence of alpha-numeric codepoints, along with _, ., [ and
  ]. Note that replacement syntax has not changed.
• FEATURE #​810:
  Add Match::is_empty and Match::len APIs.
• FEATURE #​905:
  Add an impl Default for RegexSet, with the default being the empty set.
• FEATURE #​908:
  A new method, Regex::static_captures_len, has been added which returns the
  number of capture groups in the pattern if and only if every possible match
  always contains the same number of matching groups.
• FEATURE #​955:
  Named captures can now be written as (?<name>re) in addition to
  (?P<name>re).
• FEATURE: regex-syntax now supports empty character classes.
• FEATURE: regex-syntax now has an optional std feature. (This will come
  to regex in the second release.)
• FEATURE: The Hir type in regex-syntax has had a number of simplifications
  made to it.
• FEATURE: regex-syntax has support for a new R flag for enabling CRLF
  mode. This will be supported in regex proper in the second release.
• FEATURE: regex-syntax now has proper support for "regex that never
  matches" via Hir::fail().
• FEATURE: The hir::literal module of regex-syntax has been completely
  re-worked. It now has more documentation, examples and advice.
• FEATURE: The allow_invalid_utf8 option in regex-syntax has been renamed
  to utf8, and the meaning of the boolean has been flipped.

Performance improvements:

• PERF: The upgrade to aho-corasick 1.0 may improve performance in some
  cases. It's difficult to characterize exactly which patterns this might impact,
  but if there are a small number of longish (>= 4 bytes) prefix literals, then
  it might be faster than before.

Bug fixes:

• BUG #​514:
  Improve Debug impl for Match so that it doesn't show the entire haystack.
• BUGS #​516,
  #​731:
  Fix a number of issues with printing Hir values as regex patterns.
• BUG #​610:
  Add explicit example of foo|bar in the regex syntax docs.
• BUG #​625:
  Clarify that SetMatches::len does not (regretably) refer to the number of
  matches in the set.
• BUG #​660:
  Clarify "verbose mode" in regex syntax documentation.
• BUG #​738,
  #​950:
  Fix CaptureLocations::get so that it never panics.
• BUG #​747:
  Clarify documentation for Regex::shortest_match.
• BUG #​835:
  Fix \p{Sc} so that it is equivalent to \p{Currency_Symbol}.
• BUG #​846:
  Add more clarifying documentation to the CompiledTooBig error variant.
• BUG #​854:
  Clarify that regex::Regex searches as if the haystack is a sequence of
  Unicode scalar values.
• BUG #​884:
  Replace __Nonexhaustive variants with #[non_exhaustive] attribute.
• BUG #​893:
  Optimize case folding since it can get quite slow in some pathological cases.
• BUG #​895:
  Reject (?-u:\W) in regex::Regex APIs.
• BUG #​942:
  Add a missing void keyword to indicate "no parameters" in C API.
• BUG #​965:
  Fix \p{Lc} so that it is equivalent to \p{Cased_Letter}.
• BUG #​975:
  Clarify documentation for \pX syntax.

v1.7.3

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==================
This is a small release that fixes a bug in Regex::shortest_match_at that
could cause it to panic, even when the offset given is valid.

Bug fixes:

• BUG #​969:
  Fix a bug in how the reverse DFA was called for Regex::shortest_match_at.

v1.7.2

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==================
This is a small release that fixes a failing test on FreeBSD.

Bug fixes:

• BUG #​967:
  Fix "no stack overflow" test which can fail due to the small stack size.

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[samueltardieu]

bors r+

[codspeed-hq]

CodSpeed Performance Report

Merging #436 will not alter performance

_{Comparing renovate/regex-1.x (c83e1c3) with main (c63437e)}

Summary

✅ 32 untouched benchmarks

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