microsoft / microsoft/TypeScript
Runtime error when a derived class has uninitialized decorated field and a constructor with nested super call
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@rbuckton is already working on this.
Since Jan 29, 2024.
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Description
🔎 Search Terms
decorator, initializer, constructor, super call
🕗 Version & Regression Information
- This is a crash
- This changed between versions ______ and _______
- This changed in commit or PR _______
- This is the behavior in every version I tried (after ES decorators are implemented), and I reviewed the FAQ for entries about decorators
- I was unable to test this on prior versions because _______
⏯ Playground Link
💻 Code
class Derived extends class {} {
@(function(_, context) {
context.addInitializer(function() {
this.foo = 0;
})
})
foo: any;
constructor() {
var base = super();
}
}
console.log(new Derived().foo)
🙁 Actual behavior
Runtime error: Must call super constructor in derived class before accessing 'this' or returning from derived constructor
The generated code inserts __runInitializers calls before the nested super call. It seems that the transformer only searches top level super calls. We should probably traverse the constructor node.
🙂 Expected behavior
It should print 0
Additional information about the issue
No response
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