expressive test macros (was: Report test_atomic_ops() failures consistently, via macros)

Hi,

On 2019-10-05 17:08:38 +0000, Noah Misch wrote:
> Report test_atomic_ops() failures consistently, via macros.
>
> This prints the unexpected value in more failure cases, and it removes
> forty-eight hand-maintained error messages. Back-patch to 9.5, which
> introduced these tests.

Thanks for these, that's a nice improvement.

https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=639feb92e1186e1de495d1bfdb191869cb56450a

...
+#define EXPECT_EQ_U32(result_expr, expected_expr) \
+ do { \
+ uint32 result = (result_expr); \
+ uint32 expected = (expected_expr); \
+ if (result != expected) \
+ elog(ERROR, \
+ "%s yielded %u, expected %s in file \"%s\" line %u", \
+ #result_expr, result, #expected_expr, __FILE__, __LINE__); \
+ } while (0)
...

I wonder if we should put these (and a few more, for other types), into
a more general place. I would like to have them for writing both tests
like regress.c:test_atomic_ops(), and for writing assertions that
actually display useful error messages. For the former it makes sense
to ERROR out, for the latter they ought to abort, as currently.

Seems like putting ASSERT_{EQ,LT,...}_{U32,S32,...} (or Assert_Eq_...,
but that'd imo look weirder than the inconsistency) into c.h would make
sense, and EXPECT_ somewhere in common/pg_test.h or such?

Greetings,

Andres Freund