Switch Header/Source for clangd

[theHamsta]

This snippet may be useful for users of clangd

-- in lsp-ext.lua
M = {}

M.switch_header_source = function()
    vim.lsp.buf_request(
        0,
        "textDocument/switchSourceHeader",
        vim.lsp.util.make_text_document_params(),
        function(err, _, result, _, _)
            if err then
                print(err)
            else
                vim.cmd('e '..vim.uri_to_fname(result))
            end
        end
    )
end

return M

-- in your lua config
vim.cmd [[
    command! SwitchHeaderSource lua require "lsp-ext".switch_header_source()
]]

Is something like this in the scope of nvim-lsp? Maybe we could put this in the documentation in the README.

[theHamsta]

Ooops: someone was faster: #263