Incorrect rendering with vue 3.5.15 and component props

[cjpearson]

Environment

• Operating System: Darwin
• Node Version: v22.15.0
• Nuxt Version: 3.17.4
• CLI Version: 3.25.1
• Nitro Version: 2.11.12
• Package Manager: yarn@1.22.19
• Builder: -
• User Config: compatibilityDate, devtools, modules
• Runtime Modules: @nuxt/test-utils@3.19.1
• Build Modules: -

Reproduction

https://github.com/cjpearson/test-utils-issue

Describe the bug

After upgrading to Vue 3.5.15, we have a test where the component is improperly rendered. This is the output of renderSuspended().html()

Before (3.5.14):

<div id="test-wrapper">
  <div>
    <transition-stub appear="false" persisted="false" css="true">
      <dialog open=""><button data-testid="close-button"> Close </button>
        <div>
          <div data-testid="dialog-content"> I am some modal content </div>
        </div>
      </dialog>
    </transition-stub><button data-testid="btn">Open</button>
  </div>
</div>

After (3.5.15):

<div id="test-wrapper">
  <div>
    <!--[object Object]--><button data-testid="btn">Open</button>
  </div>
</div>

While it's caused by a vue upgrade, I think this may be an issue within the test-utils because when running the application itself, everything seems to work ok.

Additional context

There seem to be a couple necessary aspects for this bug to occur:

• There's a component which has a prop of type Component
• The default value for this prop is imported through a barrel file

I've tried narrowing down the changes in Vue 3.5.15 and it looks like this change in compiler-sfc is the root cause.

Logs