pgsql: Improve regression test coverage forsrc/backend/tsearch/spell.c

Improve regression test coverage for src/backend/tsearch/spell.c.

In passing, throw an error if the AF count is too small, rather than
just silently discarding extra affix entries.

Note that the new regression test cases require installing the
updated src/backend/tsearch/dicts files.

Arthur Zakirov

Discussion: https://postgr.es/m/20180413113447.GA32474@zakirov.localdomain

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8bf358c18ec930ddfb998873369e2fc38608d3e1

Modified Files
--------------
.../tsearch/dicts/hunspell_sample_long.affix       | 25 +++++++++++++++---
.../tsearch/dicts/hunspell_sample_long.dict        |  3 +++
.../tsearch/dicts/hunspell_sample_num.affix        |  8 ++++++
src/backend/tsearch/dicts/hunspell_sample_num.dict |  3 ++-
src/backend/tsearch/spell.c                        |  9 +++++--
src/test/regress/expected/tsdicts.out              | 30 ++++++++++++++++++++++
src/test/regress/sql/tsdicts.sql                   |  5 ++++
7 files changed, 77 insertions(+), 6 deletions(-)