Write a batch of test files with made-up syntax to serve for
additional linewise checks to be manually performed whenever
the algorithm for screen dump file generation is modified.
Define a shell variable VIM_SYNTAX_SELF_TESTING to run these
tests:
cd runtime/syntax/
VIM_SYNTAX_SELF_TESTING=1 make clean test
related: #15150
Signed-off-by: Aliaksei Budavei <0x000c70@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
