This is sub test driver and cases for testing lang-c.
Currently only definition-sorter of lang-c is tested.

FILES
=======================================================
src/**
	source tree processed by tags.sh

tags.sh
	run ctags

target.tags
	generated by tags.sh

buffer/*.{h,c}
	used for making a buffer from where test.el runs
	tags-get-definitions defined in common.el.

xref/*.xref
	expected string that xref-find-definitions may generate.

NOTES
=======================================================
tags-get-definitions returns a list of hashtables. defs-to-xref
defined in test.el convert the list into a string for comparing
with the xref files.
