Problem: when nvim-web-devicons returns no highlight for an unrecognized
file extension, the icon gets nil for its highlight group. Directories
have OilDirIcon as a targetable fallback, but files have nothing.
Solution: define OilFileIcon (linked to nil, matching OilFile) and use
it as the fallback in the devicons provider when get_icon returns a nil
highlight. The mini.icons provider already returns highlights for all
files so only the devicons path needs this.
Resolves: stevearc/oil.nvim#690
Barrett Ruth
ce64ae18de
