text: import test from 'ava'
  import isolate from 'helper/isolate'
  import { assay as makeAssay } from 'make'
  const [ queryString, { queryItem } ] =
    isolate(test, 'validate/queryString', { queryItem: 'validate/queryItem' })
  
  test.serial('invalid item 0', t => {
    t.throws(() => {
      queryString([ 5 ], 0, makeAssay())
    }, {
      name: 'InvalidQueryItem',
      message: 'Invalid query item (0:0): must be object'
    })
  })
  
  test.serial('invalid item 2', t => {
    t.throws(() => {
      queryString([ {}, {}, 5 ], 8, makeAssay())
    }, {
      name: 'InvalidQueryItem',
      message: 'Invalid query item (8:2): must be object'
    })
  })
  
  test.serial('valid 0', t => {
    queryString([], 0, makeAssay())
    t.true(queryItem.notCalled)
  })
  
  test.serial('valid 1', t => {
    queryString([ {} ], 0, makeAssay())
    t.true(queryItem.calledOnce)
  })
  
  test.serial('valid 3', t => {
    queryString([ {}, {}, {} ], 0, makeAssay())
    t.true(queryItem.calledThrice)
  })
  