text: import test from 'ava'
  import nanomute from '../../index.js'
  
  test('increment value by 1 by default', t => {
      const state = nanomute({foo: 1}, 'inc(foo)')
      t.is(state.foo, 2)
  })
  
  test('increment value by positive value', t => {
      const state = nanomute({foo: 1}, 'inc(foo, 2)')
      t.is(state.foo, 3)
  })
  
  test('increment value by negative value (decrement)', t => {
      const state = nanomute({foo: 1}, 'inc(foo, -2)')
      t.is(state.foo, -1)
  })
  
  test('handle state variable not being integer (do nothing)', t => {
      const state = nanomute({foo: 'bar'}, 'inc(foo, -2)')
      t.is(state.foo, 'bar')
  })
  
  test('handle param not being integer (do nothing)', t => {
      const state = nanomute({foo: 1}, 'inc(foo, bar)')
      t.is(state.foo, 1)
  })