Обсуждение: pgsql: Rework redundant code in subtrans.c

Rework redundant code in subtrans.c

When this code was written the duplicity didn't matter, but with all the
SLRU-bank stuff we just added, it has become excessive.  Turn it into a
simpler loop with no code duplication.  Also add a test so that this
code becomes covered.

Discussion: https://postgr.es/m/202403041517.3a35jw53os65@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1a2654b32b546d25e39a0c02410049559a3d4573

Modified Files
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src/backend/access/transam/subtrans.c | 29 ++++++------------------
src/test/recovery/t/009_twophase.pl   | 42 +++++++++++++++++++++++++++++++++++
2 files changed, 49 insertions(+), 22 deletions(-)