pgsql: psql: Refine lexing of BEGIN...END blocks in CREATE FUNCTION sta

psql: Refine lexing of BEGIN...END blocks in CREATE FUNCTION statements

Only track BEGIN...END blocks if they are in a CREATE [OR REPLACE]
{FUNCTION|PROCEDURE} statement.  Ignore if in parentheses.

Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://www.postgresql.org/message-id/cee01d26fe55bc086b3bcf10bfe4e8d450e2f608.camel@cybertec.at

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/029c5ac03db72f1898ee17e417650a2e0764b239

Modified Files
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src/fe_utils/psqlscan.l             | 53 +++++++++++++++++++++++++++++++------
src/include/fe_utils/psqlscan_int.h |  8 +++++-
2 files changed, 52 insertions(+), 9 deletions(-)