Repro steps

Running API Extractor on a class with readonly properties with no type annotation but with an inline initialization crashes with error:

ERROR: Cannot read properties of undefined (reading '0')

Repro repo: https://github.com/maxakuru/api-extractor-bug

Expected result:

Readonly class properties without an initializer should ideally have their type inferred from the default value.

Actual result:

Crashes due to reading property from undefined

Details

Looks to be caused by this recent change and maybe the comment above about it being a setter isn't necessarily true.

Not sure if the ideal fix is here or in TS, but I'm guessing the output difference from tsc for readonly props with/out type annotations is intentional.

Example with annotation:

// .ts
export class Test {
  readonly foo: string = 'ok';
}

// .d.ts
export declare class Test {
  readonly foo: string = 'ok';
}

Example without annotation (fails in api-extractor):

// .ts
export class Test {
    readonly foo = "bar";
}

// .d.ts
export declare class Test {
    readonly foo = "bar"; // should this be readonly foo: "bar" ?
}

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