Problem: Insufficient testing for indent.c.
Solution: Add indent tests. (Yegappan Lakshmanan, closesvim/vim#5736)
bd7206e02c
Cherry-pick Test_ex_mode() changes from Vim patches 8.2.{0342,0347}.
Reorder test_expand_func.vim to match upstream.
Does not include listener_*() functions.
js_*() functions are N/A.
json_encode() and json_decode() didn't include tests; add some anyway
(to json_functions_spec.lua).
test_lua.vim isn't included yet, so add tests to luaeval_spec.lua.