Stub does not work for async component

[freakzlike]

When trying to stub an async component it still renders to original component instead of the stub component.

Version: 2.0.0-rc.4

import { flushPromises, mount } from '@vue/test-utils'
import { defineAsyncComponent, defineComponent } from '@vue/runtime-core'

it('should stub async component', async () => {
  const AsyncComponent = defineComponent({
    template: '<span>AsyncComponent</span>'
  })
  const StubComponent = defineComponent({
    template: '<span>StubComponent</span>'
  })
  const TestComponent = defineComponent({
    template: '<MyComponent/>',
    components: {
      MyComponent: defineAsyncComponent(async () => AsyncComponent)
    }
  })

  const wrapper = mount(TestComponent, {
    global: {
      stubs: {
        MyComponent: StubComponent
      }
    }
  })

  await flushPromises()

  expect(wrapper.html()).toContain('StubComponent')
})

Expected HTML to be <span>StubComponent</span> instead of <span>AsyncComponent</span>.

[freakzlike]

I found out that it is required to set a name in the async component and use this name in global.stubs.

import { flushPromises, mount } from '@vue/test-utils'
import { defineAsyncComponent, defineComponent } from '@vue/runtime-core'

it('should stub async component', async () => {
  const AsyncComponent = defineComponent({
    name: 'AsyncComponent',
    template: '<span>AsyncComponent</span>'
  })
  const StubComponent = defineComponent({
    template: '<span>StubComponent</span>'
  })
  const TestComponent = defineComponent({
    template: '<MyComponent/>',
    components: {
      MyComponent: defineAsyncComponent(async () => AsyncComponent)
    }
  })

  const wrapper = mount(TestComponent, {
    global: {
      stubs: {
        AsyncComponent: StubComponent
      }
    }
  })

  await flushPromises()

  expect(wrapper.html()).toContain('StubComponent')
})

I have created an pull request which adds a section to the docs for stubbing an async component.

See #516

[afontcu]

Hi! Thank you for the reproduction and the effort to open up a PR ❤️

I feel this could be handled by VTU internals, instead of asking users to add a name to a component? 🤔

[freakzlike]

@afontcu You are right. I will have a look at it

[freakzlike]

I created a PR to handle async components the same way as "sync" components. See #518