Problem:    Typos in tests; one lua line not covered by test.
Solution:   Fix typos. Add test case. (Dominique Pellé, closes #9994)

Problem:    LuaV_debug() not covered by tests.
Solution:   Add a test. (Dominique Pellé, closes #9980)

Problem:    Lua tests fail with Lua 5.4.4.
Solution:   Check messages like before Lua 5.4.3. (Jakub Kulík, closes #9652)

Problem:    Lua: can only execute on Vim command at a time.  Not easy to get
            the Vim version.
Solution:   Make vim.command() accept multiple lines.  Add vim.version().
            (Yegappan Lakshmanan, closes #8716)

Problem:    Coverity warns for not checking return value.
Solution:   If dict_add() fails give an error message.

Problem:    Cannot easily access namespace dictionaries from Lua.
Solution:   Add vim.g, vim.b, etc. (Yegappan Lakshmanan, closes #8693,
            from NeoVim)

Problem:    Lua print() does not work properly.
Solution:   Put back lua_pop().

Problem:    Crash when printing long string with Lua.
Solution:   Remove lua_pop(). (Martin Tournoij, closes #8648)

Problem:    Detecting Lua version is not reliable.
Solution:   Add "vim.lua_version". (Ozaki Kiichi, closes #8080)

Problem:    Lua test fails.
Solution:   Fix condition. (Yegappan Lakshmanan, closes #8060)