Matching issue introduced in last version of PCRE2 library ( {x} doesn't match, {X-1,X+1} does ) about pcre2

[carenas]

issue released with 10.34 and introduced in commit bf15267
Author: Philip.Hazel [email protected]
Date: Mon Sep 9 17:00:19 2019 +0000

Optimize classes such as [Aa] to be a single caseless character.

ChangeLog | 6 +++-
src/pcre2_compile.c | 85 ++++++++++++++++++++++++++++++++++++++----------
testdata/testinput10 | 2 ++
testdata/testinput12 | 2 ++
testdata/testinput2 | 2 ++
testdata/testoutput10 | 7 ++++
testdata/testoutput12-16 | 7 ++++
testdata/testoutput12-32 | 7 ++++
testdata/testoutput2 | 14 ++++++++
9 files changed, 114 insertions(+), 18 deletions(-)

and only affects the matching when the last character in the class doesn't correspond to the correct case that is shown in the data, because is registered as literal (and not caseless)

$ printf "/[Aa]{2}/\naa\n" | pcre2test
PCRE2 version 10.39 2021-10-29
/[Aa]{2}/
aa
No match

[PhilipHazel]

This was an optimization bug. [Aa] is turned into caseless 'A' but when it was last in a pattern, the "must have this character" optimization was not getting flagged as caseless. I have committed a small patch that fixes this. Thanks for the report and triage.

[guilliamxavier]

For the record: the fix is commit fdd9479 (released in version 10.40)