setComputed does not set computed values

[charliekassel]

Seems to be a bug, I've not tested using Jest.

Using vue-cli webpack tempate.
vue-test-utils@1.0.0-beta.8
Vue 2.5
Karma 1.4.1
Mocha 3.2.0

import {shallow} from 'vue-test-utils'
const cmp = {
  data () {
    return {
      a: 1
    }
  },
  computed: {
    b () {
      return this.a * 2
    }
  }
}

describe('testing vue-test-utils', () => {
  it('has default properties', () => {
    const wrapper = shallow(cmp)
    expect(wrapper.vm.a).to.equal(1)
    expect(wrapper.vm.b).to.equal(2)
  })

  it('sets data', () => {
    const wrapper = shallow(cmp)
    wrapper.setData({a: 2})
    expect(wrapper.vm.a).to.equal(2)
    expect(wrapper.vm.b).to.equal(4)
  })

  it('sets computed', () => {
    const wrapper = shallow(cmp)
    wrapper.setComputed({b: 3})
    expect(wrapper.vm.b).to.equal(3)
  })
})

  testing vue-test-utils
    ✓ has default properties
    ✓ sets data
    ✗ sets computed
	expected 2 to equal 3

[lmiller1990]

I put some console.logs inside of the setComputed function in vue test utils, and the value does appear to set -- I guess it's a bug elsewhere. Will keep playing around. I wonder if this is the same problem as #176 ...

edit: some progress, if you do

const wrapper = shallow(comp, {
  computed: { b: () => 3 }
}

It works fine, but not outside the constructor. Hmm...

edit again: this works fine. It seems that referencing a data value messes things up? Weird.

[eddyerburgh]

Should setComputed make it so the computed function always returns the value that was set until setComputed is called again. Or do you think the computed function in your example return a different value after a changes?

I have a fix if we think calling setComputed should permanently change the computed value returned.

[charliekassel]

I think if you are setting it for the test, then it should then not be mutable by the original computer getter

[charliekassel]

So that’s a yes to the first question in plain English :)

[lmiller1990]

If I do setComputed, I expect it to be the value I set it to. However I think it should reset each test - eg, every it statement, I would expect the component back in it's initial state.

[charliekassel]

Yes, agreed.