import test from 'ava' ; import { assert } from '../helpers/assert' ; import { DropString } from '../../src' ; test ( 'Can remove a string from a union of strings' , t => { type a = 'hi' | 'there' ; type b = 'hey' | 'there' | never ; assert < DropString < a , 'hi' > , 'there' > ( t ) ; assert < DropString < b , 'hey' | 'there' > , never > ( t ) ; assert < DropString < a , 'hi' | 'there' > , never > ( t ) ; } ) ;