company-mode has a builtin company-files backend that allows for
file autocompletion. However this backend is synchronous, and
therefore can block the UI and leads to freezes. In my case working
with large slow file systems this made company-files completley
unusable, Especially with M-x shell which relies heavily on file
path completion.
company-async-files provides the same completion as company-files,
but asynchronously uses find in the background to get the candidates.
This ensures that your user thread is never blocked by your completion
backend, which is the way it should be. As an added bonus, this
backend will display information about the current candidate in the
minbuffer echo area.
Since this backend relies on GNU find, it is not compatible with
Windows and does not yet support TRAMP.
Add company-async-files to company-backends afte installing this
package. company-async-files is smart enough to know when the symbol
at point is a valid filename. Therefore it is safe to use at the
begining of company-backends as the first backend for completion.
By default, company-async-files tries to provide two levels deep for
completion candidates. However this depth search can take too long to
be usefull when working on large filesystems. Therefore the depth
search will be cancelled after
company-async-files-depth-search-timeout (which defaults to 500 ms).
If timeout occurs, company-async-files will only provide candiates
in the immediate directory. This timeout value can be customized to
suite your preference.