pgsql: Improve expression evaluation test coverage.

Improve expression evaluation test coverage.

Upcoming patches are revamping expression evaluation significantly. It
therefore seems prudent to try to ensure that the coverage of the
existing evaluation code is high.

This commit adds coverage for the cases that can reasonably be
tested. There's still a bunch of unreachable error messages and such,
but otherwise this achieves nearly full regression test coverage (with
the exception of the unused GetAttributeByNum/GetAttributeByName).

Author: Andres Freund
Discussion: https://postgr.es/m/20170310194021.ek4bs4bl2khxkmll@alap3.anarazel.de

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ce38949ba23ab311f274aa4196be09d18d30e5a6

Modified Files
--------------
src/backend/executor/execQual.c | 1 +
src/test/regress/expected/arrays.out | 81 +++++++++++++++++++++++++++++++
src/test/regress/expected/boolean.out | 24 +++++++++
src/test/regress/expected/case.out | 8 +++
src/test/regress/expected/expressions.out | 77 +++++++++++++++++++++++++++++
src/test/regress/expected/inherit.out | 6 +++
src/test/regress/expected/privileges.out | 37 ++++++++++++++
src/test/regress/expected/rowtypes.out | 40 +++++++++++++++
src/test/regress/parallel_schedule | 2 +-
src/test/regress/serial_schedule | 1 +
src/test/regress/sql/arrays.sql | 33 +++++++++++++
src/test/regress/sql/boolean.sql | 20 ++++++++
src/test/regress/sql/case.sql | 5 ++
src/test/regress/sql/expressions.sql | 36 ++++++++++++++
src/test/regress/sql/inherit.sql | 1 +
src/test/regress/sql/privileges.sql | 12 +++++
src/test/regress/sql/rowtypes.sql | 23 +++++++++
17 files changed, 406 insertions(+), 1 deletion(-)