pg_unicode_fast: fix final sigma logic.
If the string is preceded only by Case Ignorable characters, don't
consider it to be a final sigma.
In the process, refactor so that the preceding and following
characters are found first, and then the rule is applied, to improve
clarity.
Discussion: https://postgr.es/m/c355354e6c3f4a7aafb047361b73db247260fca0.camel@j-davis.com
Backpatch-through: 18
Branch
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REL_19_STABLE
Details
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https://git.postgresql.org/pg/commitdiff/28d498e28031f026b8416a4c8439ddda62dfb00f
Modified Files
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src/common/unicode_case.c | 88 ++++++++++++++----------------
src/test/regress/expected/collate.utf8.out | 6 ++
src/test/regress/sql/collate.utf8.sql | 1 +
3 files changed, 47 insertions(+), 48 deletions(-)
