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|
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(11,5): error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(16,5): error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(20,5): error TS2536: Type 'keyof U' cannot be used to index type 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(21,12): error TS2536: Type 'keyof U' cannot be used to index type 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(25,5): error TS2536: Type 'K' cannot be used to index type 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(26,12): error TS2536: Type 'K' cannot be used to index type 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(30,5): error TS2322: Type 'T[keyof T] | undefined' is not assignable to type 'T[keyof T]'.
'T[keyof T]' could be instantiated with an arbitrary type which could be unrelated to 'T[keyof T] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(35,5): error TS2322: Type 'T[K] | undefined' is not assignable to type 'T[K]'.
'T[K]' could be instantiated with an arbitrary type which could be unrelated to 'T[K] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(40,5): error TS2322: Type 'U[keyof T] | undefined' is not assignable to type 'T[keyof T]'.
'T[keyof T]' could be instantiated with an arbitrary type which could be unrelated to 'U[keyof T] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(41,5): error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T] | undefined'.
Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'U[keyof T] | undefined'.
Type 'T[string]' is not assignable to type 'U[keyof T] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(45,5): error TS2322: Type 'U[K] | undefined' is not assignable to type 'T[K]'.
'T[K]' could be instantiated with an arbitrary type which could be unrelated to 'U[K] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(46,5): error TS2322: Type 'T[K]' is not assignable to type 'U[K] | undefined'.
Type 'T[keyof T]' is not assignable to type 'U[K] | undefined'.
Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'U[K] | undefined'.
Type 'T[string]' is not assignable to type 'U[K] | undefined'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(51,5): error TS2542: Index signature in type 'Readonly<T>' only permits reading.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(56,5): error TS2542: Index signature in type 'Readonly<T>' only permits reading.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(61,5): error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(61,5): error TS2542: Index signature in type 'Readonly<U>' only permits reading.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(66,5): error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(66,5): error TS2542: Index signature in type 'Readonly<U>' only permits reading.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(72,5): error TS2322: Type 'Partial<T>' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'Partial<T>'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(78,5): error TS2322: Type 'Partial<Thing>' is not assignable to type 'Partial<T>'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(88,5): error TS2322: Type 'Readonly<Thing>' is not assignable to type 'Readonly<T>'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(127,5): error TS2322: Type 'Partial<U>' is not assignable to type 'Identity<U>'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(143,5): error TS2322: Type '{ [P in keyof T]: T[P]; }' is not assignable to type '{ [P in keyof T]: U[P]; }'.
Type 'T[P]' is not assignable to type 'U[P]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(148,5): error TS2322: Type '{ [P in keyof T]: T[P]; }' is not assignable to type '{ [P in keyof U]: U[P]; }'.
Type 'keyof U' is not assignable to type 'keyof T'.
Type 'string | number | symbol' is not assignable to type 'keyof T'.
Type 'string' is not assignable to type 'keyof T'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(153,5): error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof T]: T[P]; }'.
Type 'keyof T' is not assignable to type 'K'.
'keyof T' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string | number | symbol' is not assignable to type 'K'.
'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string' is not assignable to type 'K'.
'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(158,5): error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof U]: U[P]; }'.
Type 'keyof U' is not assignable to type 'K'.
'keyof U' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string | number | symbol' is not assignable to type 'K'.
'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string' is not assignable to type 'K'.
'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(163,5): error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof T]: U[P]; }'.
Type 'keyof T' is not assignable to type 'K'.
'keyof T' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string | number | symbol' is not assignable to type 'K'.
'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
Type 'string' is not assignable to type 'K'.
'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
tests/cases/conformance/types/mapped/mappedTypeRelationships.ts(168,5): error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in K]: U[P]; }'.
Type 'T[P]' is not assignable to type 'U[P]'.
Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
==== tests/cases/conformance/types/mapped/mappedTypeRelationships.ts (28 errors) ====
function f1<T>(x: T, k: keyof T) {
return x[k];
}
function f2<T, K extends keyof T>(x: T, k: K) {
return x[k];
}
function f3<T, U extends T>(x: T, y: U, k: keyof T) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:9:13: This type parameter might need an `extends U` constraint.
}
function f4<T, U extends T, K extends keyof T>(x: T, y: U, k: K) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:14:13: This type parameter might need an `extends U` constraint.
}
function f5<T, U extends T>(x: T, y: U, k: keyof U) {
x[k] = y[k]; // Error
~~~~
!!! error TS2536: Type 'keyof U' cannot be used to index type 'T'.
y[k] = x[k]; // Error
~~~~
!!! error TS2536: Type 'keyof U' cannot be used to index type 'T'.
}
function f6<T, U extends T, K extends keyof U>(x: T, y: U, k: K) {
x[k] = y[k]; // Error
~~~~
!!! error TS2536: Type 'K' cannot be used to index type 'T'.
y[k] = x[k]; // Error
~~~~
!!! error TS2536: Type 'K' cannot be used to index type 'T'.
}
function f10<T>(x: T, y: Partial<T>, k: keyof T) {
x[k] = y[k]; // Error
~~~~
!!! error TS2322: Type 'T[keyof T] | undefined' is not assignable to type 'T[keyof T]'.
!!! error TS2322: 'T[keyof T]' could be instantiated with an arbitrary type which could be unrelated to 'T[keyof T] | undefined'.
y[k] = x[k];
}
function f11<T, K extends keyof T>(x: T, y: Partial<T>, k: K) {
x[k] = y[k]; // Error
~~~~
!!! error TS2322: Type 'T[K] | undefined' is not assignable to type 'T[K]'.
!!! error TS2322: 'T[K]' could be instantiated with an arbitrary type which could be unrelated to 'T[K] | undefined'.
y[k] = x[k];
}
function f12<T, U extends T>(x: T, y: Partial<U>, k: keyof T) {
x[k] = y[k]; // Error
~~~~
!!! error TS2322: Type 'U[keyof T] | undefined' is not assignable to type 'T[keyof T]'.
!!! error TS2322: 'T[keyof T]' could be instantiated with an arbitrary type which could be unrelated to 'U[keyof T] | undefined'.
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T] | undefined'.
!!! error TS2322: Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'U[keyof T] | undefined'.
!!! error TS2322: Type 'T[string]' is not assignable to type 'U[keyof T] | undefined'.
}
function f13<T, U extends T, K extends keyof T>(x: T, y: Partial<U>, k: K) {
x[k] = y[k]; // Error
~~~~
!!! error TS2322: Type 'U[K] | undefined' is not assignable to type 'T[K]'.
!!! error TS2322: 'T[K]' could be instantiated with an arbitrary type which could be unrelated to 'U[K] | undefined'.
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[K]' is not assignable to type 'U[K] | undefined'.
!!! error TS2322: Type 'T[keyof T]' is not assignable to type 'U[K] | undefined'.
!!! error TS2322: Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'U[K] | undefined'.
!!! error TS2322: Type 'T[string]' is not assignable to type 'U[K] | undefined'.
}
function f20<T>(x: T, y: Readonly<T>, k: keyof T) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2542: Index signature in type 'Readonly<T>' only permits reading.
}
function f21<T, K extends keyof T>(x: T, y: Readonly<T>, k: K) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2542: Index signature in type 'Readonly<T>' only permits reading.
}
function f22<T, U extends T>(x: T, y: Readonly<U>, k: keyof T) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[keyof T]' is not assignable to type 'U[keyof T]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:59:14: This type parameter might need an `extends U` constraint.
~~~~
!!! error TS2542: Index signature in type 'Readonly<U>' only permits reading.
}
function f23<T, U extends T, K extends keyof T>(x: T, y: Readonly<U>, k: K) {
x[k] = y[k];
y[k] = x[k]; // Error
~~~~
!!! error TS2322: Type 'T[K]' is not assignable to type 'U[K]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:64:14: This type parameter might need an `extends U` constraint.
~~~~
!!! error TS2542: Index signature in type 'Readonly<U>' only permits reading.
}
type Thing = { a: string, b: string };
function f30<T>(x: T, y: Partial<T>) {
x = y; // Error
~
!!! error TS2322: Type 'Partial<T>' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'Partial<T>'.
y = x;
}
function f31<T extends Thing>(x: Partial<Thing>, y: Partial<T>) {
x = y;
y = x; // Error
~
!!! error TS2322: Type 'Partial<Thing>' is not assignable to type 'Partial<T>'.
}
function f40<T>(x: T, y: Readonly<T>) {
x = y;
y = x;
}
function f41<T extends Thing>(x: Readonly<Thing>, y: Readonly<T>) {
x = y;
y = x; // Error
~
!!! error TS2322: Type 'Readonly<Thing>' is not assignable to type 'Readonly<T>'.
}
type Item = {
name: string;
}
type ItemMap = {
[x: string]: Item;
}
function f50<T extends ItemMap>(obj: T, key: keyof T) {
let item: Item = obj[key];
return obj[key].name;
}
function f51<T extends ItemMap, K extends keyof T>(obj: T, key: K) {
let item: Item = obj[key];
return obj[key].name;
}
type T1<T> = {
[P in keyof T]: T[P];
}
type T2<T> = {
[P in keyof T]: T[P];
}
function f60<U>(x: T1<U>, y: T2<U>) {
x = y;
y = x;
}
type Identity<T> = {
[P in keyof T]: T[P];
}
function f61<U>(x: Identity<U>, y: Partial<U>) {
x = y; // Error
~
!!! error TS2322: Type 'Partial<U>' is not assignable to type 'Identity<U>'.
y = x;
}
function f62<U>(x: Identity<U>, y: Readonly<U>) {
x = y;
y = x;
}
function f70<T>(x: { [P in keyof T]: T[P] }, y: { [P in keyof T]: T[P] }) {
x = y;
y = x;
}
function f71<T, U extends T>(x: { [P in keyof T]: T[P] }, y: { [P in keyof T]: U[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in keyof T]: T[P]; }' is not assignable to type '{ [P in keyof T]: U[P]; }'.
!!! error TS2322: Type 'T[P]' is not assignable to type 'U[P]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:141:14: This type parameter might need an `extends U` constraint.
}
function f72<T, U extends T>(x: { [P in keyof T]: T[P] }, y: { [P in keyof U]: U[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in keyof T]: T[P]; }' is not assignable to type '{ [P in keyof U]: U[P]; }'.
!!! error TS2322: Type 'keyof U' is not assignable to type 'keyof T'.
!!! error TS2322: Type 'string | number | symbol' is not assignable to type 'keyof T'.
!!! error TS2322: Type 'string' is not assignable to type 'keyof T'.
}
function f73<T, K extends keyof T>(x: { [P in K]: T[P] }, y: { [P in keyof T]: T[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof T]: T[P]; }'.
!!! error TS2322: Type 'keyof T' is not assignable to type 'K'.
!!! error TS2322: 'keyof T' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string | number | symbol' is not assignable to type 'K'.
!!! error TS2322: 'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string' is not assignable to type 'K'.
!!! error TS2322: 'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
}
function f74<T, U extends T, K extends keyof T>(x: { [P in K]: T[P] }, y: { [P in keyof U]: U[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof U]: U[P]; }'.
!!! error TS2322: Type 'keyof U' is not assignable to type 'K'.
!!! error TS2322: 'keyof U' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string | number | symbol' is not assignable to type 'K'.
!!! error TS2322: 'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string' is not assignable to type 'K'.
!!! error TS2322: 'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
}
function f75<T, U extends T, K extends keyof T>(x: { [P in K]: T[P] }, y: { [P in keyof T]: U[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in keyof T]: U[P]; }'.
!!! error TS2322: Type 'keyof T' is not assignable to type 'K'.
!!! error TS2322: 'keyof T' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string | number | symbol' is not assignable to type 'K'.
!!! error TS2322: 'string | number | symbol' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
!!! error TS2322: Type 'string' is not assignable to type 'K'.
!!! error TS2322: 'string' is assignable to the constraint of type 'K', but 'K' could be instantiated with a different subtype of constraint 'string | number | symbol'.
}
function f76<T, U extends T, K extends keyof T>(x: { [P in K]: T[P] }, y: { [P in K]: U[P] }) {
x = y;
y = x; // Error
~
!!! error TS2322: Type '{ [P in K]: T[P]; }' is not assignable to type '{ [P in K]: U[P]; }'.
!!! error TS2322: Type 'T[P]' is not assignable to type 'U[P]'.
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/mapped/mappedTypeRelationships.ts:166:14: This type parameter might need an `extends U` constraint.
}
function f80<T>(t: T): Partial<T> {
return t;
}
function f81<T, K extends keyof T>(t: T, k: K): Partial<T[K]> {
return t[k];
}
function f82<T, K1 extends keyof T, K2 extends keyof T[K1]>(t: T, k1: K1, k2: K2): Partial<T[K1][K2]> {
return t[k1][k2];
}
// #31070
type Numeric<T> = { [K in keyof T]?: number };
function f90<T extends { x: number }>() {
const n: Numeric<T> = { x: 1 };
}
function f<T extends { x: {} }>(): Partial<T> {
return undefined! as T;
}
|
