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|
=== tests/cases/compiler/narrowingMutualSubtypes.ts ===
// Check that `any` is a strict supertype of `unknown`
declare const ru1: { [x: string]: unknown };
>ru1 : { [x: string]: unknown; }
>x : string
declare const ra1: { [x: string]: any };
>ra1 : { [x: string]: any; }
>x : string
const a1a = [ru1, ra1]; // { [x: string]: any }[]
>a1a : { [x: string]: any; }[]
>[ru1, ra1] : { [x: string]: any; }[]
>ru1 : { [x: string]: unknown; }
>ra1 : { [x: string]: any; }
const a1b = [ra1, ru1]; // { [x: string]: any }[]
>a1b : { [x: string]: any; }[]
>[ra1, ru1] : { [x: string]: any; }[]
>ra1 : { [x: string]: any; }
>ru1 : { [x: string]: unknown; }
declare const ra2: { [x: string]: any };
>ra2 : { [x: string]: any; }
>x : string
declare const ru2: { [x: string]: unknown };
>ru2 : { [x: string]: unknown; }
>x : string
const a2a = [ru2, ra2]; // { [x: string]: any }[]
>a2a : { [x: string]: any; }[]
>[ru2, ra2] : { [x: string]: any; }[]
>ru2 : { [x: string]: unknown; }
>ra2 : { [x: string]: any; }
const a2b = [ra2, ru2]; // { [x: string]: any }[]
>a2b : { [x: string]: any; }[]
>[ra2, ru2] : { [x: string]: any; }[]
>ra2 : { [x: string]: any; }
>ru2 : { [x: string]: unknown; }
// Check that `{}` is strict supertype of any non-empty object
const c3 = {};
>c3 : {}
>{} : {}
declare const r3: { [x: string]: unknown }
>r3 : { [x: string]: unknown; }
>x : string
const a3a = [c3, r3]; // {}[]
>a3a : {}[]
>[c3, r3] : {}[]
>c3 : {}
>r3 : { [x: string]: unknown; }
const a3b = [r3, c3]; // {}[]
>a3b : {}[]
>[r3, c3] : {}[]
>r3 : { [x: string]: unknown; }
>c3 : {}
declare const r4: { [x: string]: unknown }
>r4 : { [x: string]: unknown; }
>x : string
const c4 = {};
>c4 : {}
>{} : {}
const a4a = [c4, r4]; // {}[]
>a4a : {}[]
>[c4, r4] : {}[]
>c4 : {}
>r4 : { [x: string]: unknown; }
const a4b = [r4, c4]; // {}[]
>a4b : {}[]
>[r4, c4] : {}[]
>r4 : { [x: string]: unknown; }
>c4 : {}
// Check that {} is a strict supertype of Record<string, unknown>
declare function isObject1(value: unknown): value is Record<string, unknown>;
>isObject1 : (value: unknown) => value is Record<string, unknown>
>value : unknown
function gg1(x: {}) {
>gg1 : (x: {}) => void
>x : {}
if (isObject1(x)) {
>isObject1(x) : boolean
>isObject1 : (value: unknown) => value is Record<string, unknown>
>x : {}
x; // Record<string, unknown>
>x : Record<string, unknown>
}
else {
x; // {}
>x : {}
}
x; // {}
>x : {}
}
declare function isObject2(value: unknown): value is {};
>isObject2 : (value: unknown) => value is {}
>value : unknown
function gg2(x: Record<string, unknown>) {
>gg2 : (x: Record<string, unknown>) => void
>x : Record<string, unknown>
if (isObject2(x)) {
>isObject2(x) : boolean
>isObject2 : (value: unknown) => value is {}
>x : Record<string, unknown>
x; // Record<string, unknown>
>x : Record<string, unknown>
}
else {
x; // never
>x : never
}
x; // Record<string, unknown>
>x : Record<string, unknown>
}
// Check that {} is a strict supertype of Record<string, any>
declare function isObject3(value: unknown): value is Record<string, any>;
>isObject3 : (value: unknown) => value is Record<string, any>
>value : unknown
function gg3(x: {}) {
>gg3 : (x: {}) => void
>x : {}
if (isObject3(x)) {
>isObject3(x) : boolean
>isObject3 : (value: unknown) => value is Record<string, any>
>x : {}
x; // Record<string, any>
>x : Record<string, any>
}
else {
x; // {}
>x : {}
}
x; // {}
>x : {}
}
declare function isObject4(value: unknown): value is {};
>isObject4 : (value: unknown) => value is {}
>value : unknown
function gg4(x: Record<string, any>) {
>gg4 : (x: Record<string, any>) => void
>x : Record<string, any>
if (isObject4(x)) {
>isObject4(x) : boolean
>isObject4 : (value: unknown) => value is {}
>x : Record<string, any>
x; // Record<string, any>
>x : Record<string, any>
}
else {
x; // never
>x : never
}
x; // Record<string, any>
>x : Record<string, any>
}
// Repro from #50916
type Identity<T> = {[K in keyof T]: T[K]};
>Identity : Identity<T>
type Self<T> = T extends unknown ? Identity<T> : never;
>Self : Self<T>
function is<T>(value: T): value is Self<T> {
>is : <T>(value: T) => value is Self<T>
>value : T
return true;
>true : true
}
type Union = {a: number} | {b: number} | {c: number};
>Union : { a: number; } | { b: number; } | { c: number; }
>a : number
>b : number
>c : number
function example(x: Union) {
>example : (x: Union) => void
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
if (is(x)) {}
>is(x) : boolean
>is : <T>(value: T) => value is Self<T>
>x : Union
x; // Union
>x : Union
}
function checksArrayOrObject1(obj: Record<string, any> | Record<string, any>[]) {
>checksArrayOrObject1 : (obj: Record<string, any> | Record<string, any>[]) => void
>obj : Record<string, any> | Record<string, any>[]
// "accidentally" guards the first branch on the length
if (Array.isArray(obj) && obj.length) {
>Array.isArray(obj) && obj.length : number | false
>Array.isArray(obj) : boolean
>Array.isArray : (arg: any) => arg is any[]
>Array : ArrayConstructor
>isArray : (arg: any) => arg is any[]
>obj : Record<string, any> | Record<string, any>[]
>obj.length : number
>obj : any[] | Record<string, any>[]
>length : number
for (let key in obj) {
>key : string
>obj : any[] | Record<string, any>[]
if (obj[key] !== undefined) {
>obj[key] !== undefined : boolean
>obj[key] : any
>obj : any[] | Record<string, any>[]
>key : string
>undefined : undefined
console.log(obj[key])
>console.log(obj[key]) : void
>console.log : (...data: any[]) => void
>console : Console
>log : (...data: any[]) => void
>obj[key] : any
>obj : any[] | Record<string, any>[]
>key : string
}
}
}
else {
// 'obj' should probably not include an array type here.
for (let key in obj) {
>key : string
>obj : any[] | Record<string, any>
if (obj[key] !== undefined) {
>obj[key] !== undefined : boolean
>obj[key] : any
>obj : any[] | Record<string, any>
>key : string
>undefined : undefined
console.log(obj[key])
>console.log(obj[key]) : void
>console.log : (...data: any[]) => void
>console : Console
>log : (...data: any[]) => void
>obj[key] : any
>obj : any[] | Record<string, any>
>key : string
}
}
}
}
function checksArrayOrObject2(obj: Record<string, any> | Record<string, any>[]) {
>checksArrayOrObject2 : (obj: Record<string, any> | Record<string, any>[]) => void
>obj : Record<string, any> | Record<string, any>[]
if (Array.isArray(obj)) {
>Array.isArray(obj) : boolean
>Array.isArray : (arg: any) => arg is any[]
>Array : ArrayConstructor
>isArray : (arg: any) => arg is any[]
>obj : Record<string, any> | Record<string, any>[]
// obj should only be an array type here
for (let key in obj) {
>key : string
>obj : any[] | Record<string, any>[]
if (obj[key] !== undefined) {
>obj[key] !== undefined : boolean
>obj[key] : any
>obj : any[] | Record<string, any>[]
>key : string
>undefined : undefined
console.log(obj[key])
>console.log(obj[key]) : void
>console.log : (...data: any[]) => void
>console : Console
>log : (...data: any[]) => void
>obj[key] : any
>obj : any[] | Record<string, any>[]
>key : string
}
}
}
else {
// 'obj' should probably not include an array type here.
for (let key in obj) {
>key : string
>obj : Record<string, any>
if (obj[key] !== undefined) {
>obj[key] !== undefined : boolean
>obj[key] : any
>obj : Record<string, any>
>key : string
>undefined : undefined
console.log(obj[key])
>console.log(obj[key]) : void
>console.log : (...data: any[]) => void
>console : Console
>log : (...data: any[]) => void
>obj[key] : any
>obj : Record<string, any>
>key : string
}
}
}
}
|
