/
conditionalTypesSimplifyWhenTrivial.types
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conditionalTypesSimplifyWhenTrivial.types
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=== tests/cases/compiler/conditionalTypesSimplifyWhenTrivial.ts ===
const fn1 = <Params>(
>fn1 : <Params>(params: Pick<Params, Exclude<keyof Params, never>>) => Params
><Params>( params: Pick<Params, Exclude<keyof Params, never>>,): Params => params : <Params>(params: Pick<Params, Exclude<keyof Params, never>>) => Params
params: Pick<Params, Exclude<keyof Params, never>>,
>params : Pick<Params, Exclude<keyof Params, never>>
): Params => params;
>params : Pick<Params, Exclude<keyof Params, never>>
function fn2<T>(x: Exclude<T, never>) {
>fn2 : <T>(x: Exclude<T, never>) => void
>x : Exclude<T, never>
var y: T = x;
>y : T
>x : Exclude<T, never>
x = y;
>x = y : T
>x : Exclude<T, never>
>y : T
}
const fn3 = <Params>(
>fn3 : <Params>(params: Pick<Params, Extract<keyof Params, keyof Params>>) => Params
><Params>( params: Pick<Params, Extract<keyof Params, keyof Params>>,): Params => params : <Params>(params: Pick<Params, Extract<keyof Params, keyof Params>>) => Params
params: Pick<Params, Extract<keyof Params, keyof Params>>,
>params : Pick<Params, Extract<keyof Params, keyof Params>>
): Params => params;
>params : Pick<Params, Extract<keyof Params, keyof Params>>
function fn4<T>(x: Extract<T, T>) {
>fn4 : <T>(x: Extract<T, T>) => void
>x : Extract<T, T>
var y: T = x;
>y : T
>x : Extract<T, T>
x = y;
>x = y : T
>x : Extract<T, T>
>y : T
}
declare var x: Extract<number | string, any>; // Should be `numebr | string` and not `any`
>x : string | number
type ExtractWithDefault<T, U, D = never> = T extends U ? T : D;
>ExtractWithDefault : ExtractWithDefault<T, U, D>
type ExcludeWithDefault<T, U, D = never> = T extends U ? D : T;
>ExcludeWithDefault : ExcludeWithDefault<T, U, D>
const fn5 = <Params>(
>fn5 : <Params>(params: Pick<Params, ExcludeWithDefault<keyof Params, never, never>>) => Params
><Params>( params: Pick<Params, ExcludeWithDefault<keyof Params, never>>,): Params => params : <Params>(params: Pick<Params, ExcludeWithDefault<keyof Params, never, never>>) => Params
params: Pick<Params, ExcludeWithDefault<keyof Params, never>>,
>params : Pick<Params, ExcludeWithDefault<keyof Params, never, never>>
): Params => params;
>params : Pick<Params, ExcludeWithDefault<keyof Params, never, never>>
function fn6<T>(x: ExcludeWithDefault<T, never>) {
>fn6 : <T>(x: ExcludeWithDefault<T, never, never>) => void
>x : ExcludeWithDefault<T, never, never>
var y: T = x;
>y : T
>x : ExcludeWithDefault<T, never, never>
x = y;
>x = y : T
>x : ExcludeWithDefault<T, never, never>
>y : T
}
const fn7 = <Params>(
>fn7 : <Params>(params: Pick<Params, ExtractWithDefault<keyof Params, keyof Params, never>>) => Params
><Params>( params: Pick<Params, ExtractWithDefault<keyof Params, keyof Params>>,): Params => params : <Params>(params: Pick<Params, ExtractWithDefault<keyof Params, keyof Params, never>>) => Params
params: Pick<Params, ExtractWithDefault<keyof Params, keyof Params>>,
>params : Pick<Params, ExtractWithDefault<keyof Params, keyof Params, never>>
): Params => params;
>params : Pick<Params, ExtractWithDefault<keyof Params, keyof Params, never>>
function fn8<T>(x: ExtractWithDefault<T, T>) {
>fn8 : <T>(x: ExtractWithDefault<T, T, never>) => void
>x : ExtractWithDefault<T, T, never>
var y: T = x;
>y : T
>x : ExtractWithDefault<T, T, never>
x = y;
>x = y : T
>x : ExtractWithDefault<T, T, never>
>y : T
}
type TemplatedConditional<TCheck, TExtends, TTrue, TFalse> = TCheck extends TExtends ? TTrue : TFalse;
>TemplatedConditional : TemplatedConditional<TCheck, TExtends, TTrue, TFalse>
const fn9 = <Params>(
>fn9 : <Params>(params: Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>) => Params
><Params>( params: Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>,): Params => params : <Params>(params: Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>) => Params
params: Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>,
>params : Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>
): Params => params;
>params : Pick<Params, TemplatedConditional<keyof Params, never, never, keyof Params>>
function fn10<T>(x: TemplatedConditional<T, never, never, T>) {
>fn10 : <T>(x: TemplatedConditional<T, never, never, T>) => void
>x : TemplatedConditional<T, never, never, T>
var y: T = x;
>y : T
>x : TemplatedConditional<T, never, never, T>
x = y;
>x = y : T
>x : TemplatedConditional<T, never, never, T>
>y : T
}
const fn11 = <Params>(
>fn11 : <Params>(params: Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>) => Params
><Params>( params: Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>,): Params => params : <Params>(params: Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>) => Params
params: Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>,
>params : Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>
): Params => params;
>params : Pick<Params, TemplatedConditional<keyof Params, keyof Params, keyof Params, never>>
function fn12<T>(x: TemplatedConditional<T, T, T, never>) {
>fn12 : <T>(x: TemplatedConditional<T, T, T, never>) => void
>x : TemplatedConditional<T, T, T, never>
var y: T = x;
>y : T
>x : TemplatedConditional<T, T, T, never>
x = y;
>x = y : T
>x : TemplatedConditional<T, T, T, never>
>y : T
}
declare var z: any;
>z : any
const zee = z!!!; // since x is `any`, `x extends null | undefined` should be both true and false - and thus yield `any`
>zee : any
>z!!! : any
>z!! : any
>z! : any
>z : any