[PATCH v2] test: add "set -u" to test-lib.sh

[David Bremner]

Tomi Ollila <tomi.ollila at iki.fi> writes:

> This prohibits unset variables to expand to empty strings.
> Without this e.g misspelled variables cause unintentional results.
>
> Now all the test variables are either initialized, or in case of
> optional arguments and user-provided environment variables (i.e.
> when it is not know whethet the variable is set) the form
> ${variable-} is used.
>
> Two unusable lines (leftovers?) in T360-symbol-hiding.sh were removed;
> this was the only non-lib test code that needed to be edited for this
> change to work.

Hi Tomi;

I like the idea, but currently I get many test failures with

/test-lib.sh: line 926: test_subtest_missing_external_prereq_: unbound variable

d