/
controlFlowGenericTypes.errors.txt
251 lines (207 loc) · 7.97 KB
/
controlFlowGenericTypes.errors.txt
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tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(49,15): error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'Box<T>'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(55,15): error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'Box<unknown>'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(81,11): error TS2339: Property 'foo' does not exist on type 'MyUnion'.
Property 'foo' does not exist on type 'AA'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(90,44): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(91,11): error TS2339: Property 'foo' does not exist on type 'MyUnion'.
Property 'foo' does not exist on type 'AA'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(156,16): error TS2532: Object is possibly 'undefined'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(167,9): error TS2532: Object is possibly 'undefined'.
tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts(168,9): error TS2532: Object is possibly 'undefined'.
==== tests/cases/conformance/controlFlow/controlFlowGenericTypes.ts (8 errors) ====
function f1<T extends string | undefined>(x: T, y: { a: T }, z: [T]): string {
if (x) {
x;
x.length;
return x;
}
if (y.a) {
y.a.length;
return y.a;
}
if (z[0]) {
z[0].length;
return z[0];
}
return "hello";
}
function f2<T>(x: Extract<T, string | undefined> | null): string {
if (x) {
x;
x.length;
return x;
}
return "hello";
}
interface Box<T> {
item: T;
}
declare function isBox(x: any): x is Box<unknown>;
declare function isUndefined(x: unknown): x is undefined;
declare function unbox<T>(x: Box<T>): T;
function g1<T extends Box<T> | undefined>(x: T) {
if (isBox(x)) {
unbox(x);
}
}
function g2<T extends Box<T> | undefined>(x: T) {
if (!isUndefined(x)) {
unbox(x);
}
}
function g3<T extends Box<T> | undefined>(x: T) {
if (!isBox(x)) {
unbox(x); // Error
~
!!! error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'Box<T>'.
}
}
function g4<T extends Box<T> | undefined>(x: T) {
if (isUndefined(x)) {
unbox(x); // Error
~
!!! error TS2345: Argument of type 'undefined' is not assignable to parameter of type 'Box<unknown>'.
}
}
// Repro from #13995
declare function takeA(val: 'A'): void;
export function bounceAndTakeIfA<AB extends 'A' | 'B'>(value: AB): AB {
if (value === 'A') {
takeA(value);
return value;
}
else {
return value;
}
}
// Repro from #13995
type Common = { id: number };
type AA = { tag: 'A', id: number };
type BB = { tag: 'B', id: number, foo: number };
type MyUnion = AA | BB;
const fn = (value: MyUnion) => {
value.foo; // Error
~~~
!!! error TS2339: Property 'foo' does not exist on type 'MyUnion'.
!!! error TS2339: Property 'foo' does not exist on type 'AA'.
if ('foo' in value) {
value.foo;
}
if (value.tag === 'B') {
value.foo;
}
};
const fn2 = <T extends MyUnion>(value: T): MyUnion => {
~~~~~~~
!!! error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value.
value.foo; // Error
~~~
!!! error TS2339: Property 'foo' does not exist on type 'MyUnion'.
!!! error TS2339: Property 'foo' does not exist on type 'AA'.
if ('foo' in value) {
value.foo;
}
if (value.tag === 'B') {
value.foo;
}
};
// Repro from #13995
type A1 = {
testable: true
doTest: () => void
}
type B1 = {
testable: false
};
type Union = A1 | B1
function notWorking<T extends Union>(object: T) {
if (!object.testable) return;
object.doTest();
}
// Repro from #42939
interface A {
a: number | null;
};
function get<K extends keyof A>(key: K, obj: A): number {
const value = obj[key];
if (value !== null) {
return value;
}
return 0;
};
// Repro from #44093
class EventEmitter<ET> {
off<K extends keyof ET>(...args: [K, number] | [unknown, string]):void {}
}
function once<ET, T extends EventEmitter<ET>>(emittingObject: T, eventName: keyof ET): void {
emittingObject.off(eventName, 0);
emittingObject.off(eventName as typeof eventName, 0);
}
// In an element access obj[x], we consider obj to be in a constraint position, except when obj is of
// a generic type without a nullable constraint and x is a generic type. This is because when both obj
// and x are of generic types T and K, we want the resulting type to be T[K].
function fx1<T, K extends keyof T>(obj: T, key: K) {
const x1 = obj[key];
const x2 = obj && obj[key];
}
function fx2<T extends Record<keyof T, string>, K extends keyof T>(obj: T, key: K) {
const x1 = obj[key];
const x2 = obj && obj[key];
}
function fx3<T extends Record<keyof T, string> | undefined, K extends keyof T>(obj: T, key: K) {
const x1 = obj[key]; // Error
~~~
!!! error TS2532: Object is possibly 'undefined'.
const x2 = obj && obj[key];
}
// Repro from #44166
class TableBaseEnum<
PublicSpec extends Record<keyof InternalSpec, any>,
InternalSpec extends Record<keyof PublicSpec, any> | undefined = undefined> {
m() {
let iSpec = null! as InternalSpec;
iSpec[null! as keyof InternalSpec]; // Error, object possibly undefined
~~~~~
!!! error TS2532: Object is possibly 'undefined'.
iSpec[null! as keyof PublicSpec]; // Error, object possibly undefined
~~~~~
!!! error TS2532: Object is possibly 'undefined'.
if (iSpec === undefined) {
return;
}
iSpec[null! as keyof InternalSpec];
iSpec[null! as keyof PublicSpec];
}
}
// Repros from #45145
function f10<T extends { a: string } | undefined>(x: T, y: Partial<T>) {
y = x;
}
type SqlInsertSet<T> = T extends undefined ? object : { [P in keyof T]: unknown };
class SqlTable<T> {
protected validateRow(_row: Partial<SqlInsertSet<T>>): void {
}
public insertRow(row: SqlInsertSet<T>) {
this.validateRow(row);
}
}
// Repro from #46495
interface Button {
type: "button";
text: string;
}
interface Checkbox {
type: "checkbox";
isChecked: boolean;
}
type Control = Button | Checkbox;
function update<T extends Control, K extends keyof T>(control : T | undefined, key: K, value: T[K]): void {
if (control !== undefined) {
control[key] = value;
}
}
// Repro from #50465
type Column<T> = (keyof T extends never ? { id?: number | string } : { id: T }) & { title?: string; }
function getColumnProperty<T>(column: Column<T>, key: keyof Column<T>) {
return column[key];
}