Problem:
tagfunc failed in a weird buffer (either a directory or some other
non-file buffer, I don't remember):
E987: Invalid return value from tagfunc
E5108: Error executing lua …/runtime/lua/vim/lsp/util.lua:311: EISDIR: illegal operation on a directory
stack traceback:
at this line:
local data = assert(uv.fs_read(fd, stat.size, 0))
Solution:
Check for directory.
50f006b617
