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Description
Bug Report
The following code used to work on 4.2.3, but does not build with 4.3.2, reporting the error on the last line
type ObjectFixedKeys<T extends object> = {
[K in keyof T]: string extends K ? never : K
} extends { [_ in keyof T]: infer U }
? U
: never
type DistributeKeysUnion<U> = U extends string
? { [K in U]: any }
: never
type ObjectDictionaryKeys<T extends object> = Exclude<
T,
DistributeKeysUnion<ObjectFixedKeys<T>>
>
type Condition = { $and: Array<Condition> }
| { $or: Array<Condition> }
| { [member: string]: string }
type O = ObjectFixedKeys<Condition>
type D = DistributeKeysUnion<ObjectFixedKeys<Condition>>
declare const s: string
type CT = ObjectDictionaryKeys<Condition>
declare const ct : CT
const h = ct[s]Error:
Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'CT'.
No index signature with a parameter of type 'string' was found on type 'CT'.
🕗 Version & Regression Information
I tracked the regression to the version 4.3.0-dev.20210422
Probably related to 8ea4ec9
⏯ Playground Link
Playground link with relevant code
Note how the last line is evaluated to never, however if you select version 4.2.3 it gets evaluated to "foo" | "bar" as expected.