Regression issue in v1.1.3 with slot content evaluation

[bponomarenko]

Version

1.2.2

Reproduction link

github.com

Steps to reproduce

• Install dependencies with npm install
• Run test – npm run test

What is expected?

Test will successfully pass

What is actually happening?

Test is failing

---

Test would be failing unless @vue/test-utils downgraded to the v1.1.2 or lower, which makes me certain it was introduced in v1.1.3.

[bponomarenko]

@xanf Hey Illya. Sorry for tagging you here, but it seems that changes in #1752 may be related to this issue. If you'll have time to look into it, that would be great. Maybe it would be easy for you to spot an issue, I'm quite new to this codebase.

[bponomarenko]

Here is a unit test to reproduce the issue (when added to the setProps.spec.js)

  it.only('should preserve component instance references when setting properties with setProps', async () => {
    const SlotComponent = { template: '<div></div>' }
    const wrapper = mountingMethod(ComponentWithSlots, {
      slots: { default: SlotComponent }
    })
    expect(wrapper.vm.$slots.default[0].componentInstance).toBeDefined()
    // Doesn't matter which property to set, even non-defined one
    await wrapper.setProps({ test: true })
    // Should not depend on "setProps" calls
    expect(wrapper.vm.$slots.default[0].componentInstance).toBeDefined()
  })