Specifically, functions that are run in the context of the test runner
are put in module `test/testutil.lua` while the functions that are run
in the context of the test session are put in
`test/functional/testnvim.lua`.
Closes https://github.com/neovim/neovim/issues/27004.
Use unique filenames to avoid test conflicts.
Use read_file() instead of io.popen(), to ensures the file is closed.
Use helpers.rmdir(), it is far more robust than lfs.
closes#7911
The flag enables the current local directory set by ":lcd" to be saved
to views which is the current default behaviour. The option can be
removed to disable this behaviour.
closes#7435
vim-patch:8.0.1289