import { assert_exception } from "https://deno.land/x/denops_std@v6.3.0/function/vim/mod.ts";
When v:exception does not contain the string {error} an error
message is added to v:errors. Also see assert-return.
This can be used to assert that a command throws an exception.
Using the error number, followed by a colon, avoids problems
with translations:
try
commandthatfails
call assert_false(1, 'command should have failed')
catch
call assert_exception('E492:')
endtry