Tom Lane 6cfaffc0dd Fix regexport.c to behave sanely with lookaround constraints. ... regexport.c thought it could just ignore LACON arcs, but the correct behavior is to treat them as satisfiable while consuming zero input (rather reminiscently of commit 9f1e642d5). Otherwise, the emitted simplified-NFA representation may contain no paths leading from initial to final state, which unsurprisingly confuses pg_trgm, as seen in bug #14623 from Jeff Janes. Since regexport's output representation has no concept of an arc that consumes zero input, recurse internally to find the next normal arc(s) after any LACON transitions. We'd be forced into changing that representation if a LACON could be the last arc reaching the final state, but fortunately the regex library never builds NFAs with such a configuration, so there always is a next normal arc. Back-patch to 9.3 where this logic was introduced. Discussion: https://postgr.es/m/20170413180503.25948.94871@wrigleys.postgresql.org		2017-04-13 17:18:35 -04:00
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pg_trgm.sql	Fix regexport.c to behave sanely with lookaround constraints.	2017-04-13 17:18:35 -04:00
pg_word_trgm.sql	Add files forgotten in f576b17cd6	2016-03-16 19:23:41 +03:00