itwin-fronted3.7.5 =>itwin4.0.3

[VWlf]

During the upgrade process from itwin 3.7.5 to itwin 4.0.3, it was discovered during project compilation that optional chains were added in 4.0.3 The relevant code of the error message is as follows:

[aruniverse]

Please share the error

[VWlf]

Just released, could you please help me take a look

[VWlf]

I am trying to add a new feature for “?.”or"??" In <babel.config.js> Adaptation, but no effect. By the way, my current project is built by Vue2,Node is 20.12.2

Babel's related dependencies are all above 7.0.0. Please help me identify the problem. If you need more problem descriptions, please contact me. Thank you very much

[aruniverse]

We don't use babel directly, we use a fork of create-react-app, you can look at the dependencies we use, and our config

I see you added the plugin for optional chaining, but looks like it was for the propsal, maybe you should be using https://babeljs.io/docs/babel-plugin-syntax-optional-chaining.html

[VWlf]

If Babel uses Propsal in version 7.0 and syntax in version 6.0, I have tried both but failed. I will try what you saidhttps://github.com/imodeljs/create-react-app/blob/imodeljs/packages/react-scripts/package.json
How was this added to the Vue project for use? Was it added in package.json

[VWlf]

Sorry, I saw it. It's the link at the back. I'll give it a try. Thank you very much！！

[VWlf]

I know the answer, if you're configuring it in a Vue2 project, you'll need to add it to your vue.config.js:
rules: [ { test: /\.js$/, include: /node_modules/, use: { loader: 'babel-loader' } } ]
Install dependencies:
npm install -g babel-loader @babel/core @babel/preset-env