text: import { assert } from 'chai'
  import { describe, it } from 'mocha'
  
  import { mergeDeeply } from './util.js'
  
  describe('utilities', function () {
    it('mergeDeeply', function () {
      const a = {
        x: 1,
        y: { a: -1, c: 4 }
      }
      const b = {
        y: { a: 2, b: 3 },
        z: 5
      }
  
      assert.deepEqual(mergeDeeply(a, b), {
        x: 1,
        y: { a: 2, b: 3, c: 4 },
        z: 5
      })
    })
  })
  