fix: convert emits to props, fix #13104

[so1ve]

What kind of change does this PR introduce? (check at least one)

• Bugfix: fixes Vue 2.7 strictTemplates error #13104
• Feature
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• It's submitted to the main branch for v2.x (or to a previous version branch)
• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)
• All tests are passing: https://github.com/vuejs/vue/blob/dev/.github/CONTRIBUTING.md#development-setup
• New/updated tests are included

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature (to avoid wasting your time, it's best to open a suggestion issue first and wait for approval before working on it)

Converts emits to props.

Other information:

[yyx990803]

@so1ve I tested this locally and it doesn't seem to fix #13104 - is this something you still intend to work on? We might be able to get this in the final patch release before EOL.

[so1ve]

I'll take a look and add tests

[so1ve]

I need some help, I couldn't get emits from extends and mixin work...

[so1ve]

This fix is beyond my capabilities and I hope someone else can fix it.

[zcf0508]

@so1ve I tested this locally and it doesn't seem to fix #13104 - is this something you still intend to work on? We might be able to get this in the final patch release before EOL.

#13133

https://github.com/vuejs/vue/pull/13133/files#diff-d26123bca327fbaf4e0ce33d7085fcaf9f4a39be4f76a1d0c15e0843afb1af9fR153

Maybe this is the key line to resolve the error of #13104

[so1ve]

No, your implementation doesn't take extends and mixin into account

[zcf0508]

No, your implementation doesn't take extends and mixin into account

Yes, you are right, I'm working on it. But now I have some questions. I see you add a test that you can get emit functions fromprops in setup function, but the props does not expose those functions. It is a right type test?

[so1ve]

Yes, because it can be undefined

[zcf0508]

Does it mean that If a component use props.onFoo in runtime, the function will never work? Is the onFoo only used for type inference?

[so1ve]

Yes, seemed to be true

[zcf0508]

#13133

I think it works with extends and mixin now.