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tests/cases/compiler/excessPropertyCheckWithUnions.ts(10,30): error TS2322: Type '{ tag: "T"; a1: string; }' is not assignable to type 'ADT'.
Object literal may only specify known properties, and 'a1' does not exist in type '{ tag: "T"; }'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(11,21): error TS2322: Type '{ tag: "A"; d20: number; }' is not assignable to type 'ADT'.
Object literal may only specify known properties, and 'd20' does not exist in type '{ tag: "A"; a1: string; }'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(12,1): error TS2322: Type '{ tag: "D"; }' is not assignable to type 'ADT'.
Property 'd20' is missing in type '{ tag: "D"; }' but required in type '{ tag: "D"; d20: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20; }'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(33,28): error TS2322: Type '{ tag: "A"; x: string; extra: number; }' is not assignable to type 'Ambiguous'.
Object literal may only specify known properties, and 'extra' does not exist in type 'Ambiguous'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(34,26): error TS2322: Type '{ tag: "A"; y: number; extra: number; }' is not assignable to type 'Ambiguous'.
Object literal may only specify known properties, and 'extra' does not exist in type 'Ambiguous'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(39,1): error TS2322: Type '{ tag: "A"; }' is not assignable to type 'Ambiguous'.
Type '{ tag: "A"; }' is not assignable to type '{ tag: "C"; }'.
Types of property 'tag' are incompatible.
Type '"A"' is not assignable to type '"C"'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(40,1): error TS2322: Type '{ tag: "A"; z: true; }' is not assignable to type 'Ambiguous'.
Type '{ tag: "A"; z: true; }' is not assignable to type '{ tag: "B"; z: boolean; }'.
Types of property 'tag' are incompatible.
Type '"A"' is not assignable to type '"B"'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(49,35): error TS2322: Type '{ a: 1; b: 1; first: string; second: string; }' is not assignable to type 'Overlapping'.
Object literal may only specify known properties, and 'second' does not exist in type '{ a: 1; b: 1; first: string; }'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(50,35): error TS2322: Type '{ a: 1; b: 1; first: string; third: string; }' is not assignable to type 'Overlapping'.
Object literal may only specify known properties, and 'third' does not exist in type '{ a: 1; b: 1; first: string; }'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(66,9): error TS2322: Type '{ kind: "A"; n: { a: string; b: string; }; }' is not assignable to type 'AB'.
Types of property 'n' are incompatible.
Type '{ a: string; b: string; }' is not assignable to type 'AN'.
Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(87,5): error TS2322: Type '{ tag: "button"; type: "submit"; href: string; }' is not assignable to type 'Union'.
Object literal may only specify known properties, and 'href' does not exist in type 'Button'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(108,5): error TS2322: Type 'string' is not assignable to type 'IValue'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(113,67): error TS2322: Type 'string' is not assignable to type 'number'.
tests/cases/compiler/excessPropertyCheckWithUnions.ts(114,63): error TS2322: Type 'string' is not assignable to type 'number'.
==== tests/cases/compiler/excessPropertyCheckWithUnions.ts (14 errors) ====
type ADT = {
tag: "A",
a1: string
} | {
tag: "D",
d20: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20
} | {
tag: "T",
}
let wrong: ADT = { tag: "T", a1: "extra" }
~~~~~~~~~~~
!!! error TS2322: Type '{ tag: "T"; a1: string; }' is not assignable to type 'ADT'.
!!! error TS2322: Object literal may only specify known properties, and 'a1' does not exist in type '{ tag: "T"; }'.
wrong = { tag: "A", d20: 12 }
~~~~~~~
!!! error TS2322: Type '{ tag: "A"; d20: number; }' is not assignable to type 'ADT'.
!!! error TS2322: Object literal may only specify known properties, and 'd20' does not exist in type '{ tag: "A"; a1: string; }'.
wrong = { tag: "D" }
~~~~~
!!! error TS2322: Type '{ tag: "D"; }' is not assignable to type 'ADT'.
!!! error TS2322: Property 'd20' is missing in type '{ tag: "D"; }' but required in type '{ tag: "D"; d20: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20; }'.
!!! related TS2728 tests/cases/compiler/excessPropertyCheckWithUnions.ts:6:5: 'd20' is declared here.
type Ambiguous = {
tag: "A",
x: string
} | {
tag: "A",
y: number
} | {
tag: "B",
z: boolean
} | {
tag: "C"
}
let amb: Ambiguous
// no error for ambiguous tag, even when it could satisfy both constituents at once
amb = { tag: "A", x: "hi" }
amb = { tag: "A", y: 12 }
amb = { tag: "A", x: "hi", y: 12 }
// correctly error on excess property 'extra', even when ambiguous
amb = { tag: "A", x: "hi", extra: 12 }
~~~~~~~~~
!!! error TS2322: Type '{ tag: "A"; x: string; extra: number; }' is not assignable to type 'Ambiguous'.
!!! error TS2322: Object literal may only specify known properties, and 'extra' does not exist in type 'Ambiguous'.
amb = { tag: "A", y: 12, extra: 12 }
~~~~~~~~~
!!! error TS2322: Type '{ tag: "A"; y: number; extra: number; }' is not assignable to type 'Ambiguous'.
!!! error TS2322: Object literal may only specify known properties, and 'extra' does not exist in type 'Ambiguous'.
// assignability errors still work.
// But note that the error for `z: true` is the fallback one of reporting on
// the last constituent since assignability error reporting can't find a single best discriminant either.
amb = { tag: "A" }
~~~
!!! error TS2322: Type '{ tag: "A"; }' is not assignable to type 'Ambiguous'.
!!! error TS2322: Type '{ tag: "A"; }' is not assignable to type '{ tag: "C"; }'.
!!! error TS2322: Types of property 'tag' are incompatible.
!!! error TS2322: Type '"A"' is not assignable to type '"C"'.
amb = { tag: "A", z: true }
~~~
!!! error TS2322: Type '{ tag: "A"; z: true; }' is not assignable to type 'Ambiguous'.
!!! error TS2322: Type '{ tag: "A"; z: true; }' is not assignable to type '{ tag: "B"; z: boolean; }'.
!!! error TS2322: Types of property 'tag' are incompatible.
!!! error TS2322: Type '"A"' is not assignable to type '"B"'.
type Overlapping =
| { a: 1, b: 1, first: string }
| { a: 2, second: string }
| { b: 3, third: string }
let over: Overlapping
// these two are still errors despite their doubled up discriminants
over = { a: 1, b: 1, first: "ok", second: "error" }
~~~~~~~~~~~~~~~
!!! error TS2322: Type '{ a: 1; b: 1; first: string; second: string; }' is not assignable to type 'Overlapping'.
!!! error TS2322: Object literal may only specify known properties, and 'second' does not exist in type '{ a: 1; b: 1; first: string; }'.
over = { a: 1, b: 1, first: "ok", third: "error" }
~~~~~~~~~~~~~~
!!! error TS2322: Type '{ a: 1; b: 1; first: string; third: string; }' is not assignable to type 'Overlapping'.
!!! error TS2322: Object literal may only specify known properties, and 'third' does not exist in type '{ a: 1; b: 1; first: string; }'.
// Freshness disappears after spreading a union
declare let t0: { a: any, b: any } | { d: any, e: any }
declare let t1: { a: any, b: any, c: any } | { c: any, d: any, e: any }
let t2 = { ...t1 }
t0 = t2
// Nested excess property checks work with discriminated unions
type AN = { a: string } | { c: string }
type BN = { b: string }
type AB = { kind: "A", n: AN } | { kind: "B", n: BN }
const abab: AB = {
kind: "A",
n: {
a: "a",
b: "b", // excess -- kind: "A"
~~~~~~
!!! error TS2322: Type '{ kind: "A"; n: { a: string; b: string; }; }' is not assignable to type 'AB'.
!!! error TS2322: Types of property 'n' are incompatible.
!!! error TS2322: Type '{ a: string; b: string; }' is not assignable to type 'AN'.
!!! error TS2322: Object literal may only specify known properties, and 'b' does not exist in type 'AN'.
}
}
const abac: AB = {
kind: "A",
n: {
a: "a",
c: "c", // ok -- kind: "A", an: { a: string } | { c: string }
}
}
// Excess property checks must match all discriminable properties
type Button = { tag: 'button'; type?: 'submit'; };
type Anchor = { tag: 'a'; type?: string; href: string };
type Union = Button | Anchor;
const obj: Union = {
tag: 'button',
type: 'submit',
// should have error here
href: 'foo',
~~~~~~~~~~~
!!! error TS2322: Type '{ tag: "button"; type: "submit"; href: string; }' is not assignable to type 'Union'.
!!! error TS2322: Object literal may only specify known properties, and 'href' does not exist in type 'Button'.
};
// Repro from #34611
interface IValue {
value: string
}
interface StringKeys {
[propertyName: string]: IValue;
};
interface NumberKeys {
[propertyName: number]: IValue;
}
type ObjectDataSpecification = StringKeys | NumberKeys;
const dataSpecification: ObjectDataSpecification = { // Error
foo: "asdfsadffsd"
~~~
!!! error TS2322: Type 'string' is not assignable to type 'IValue'.
};
// Repro from #34611
const obj1: { [x: string]: number } | { [x: number]: number } = { a: 'abc' }; // Error
~
!!! error TS2322: Type 'string' is not assignable to type 'number'.
const obj2: { [x: string]: number } | { a: number } = { a: 5, c: 'abc' }; // Error
~
!!! error TS2322: Type 'string' is not assignable to type 'number'.
// Repro from #33732
interface I1 {
prop1: string;
}
interface I2 {
prop2: string;
}
interface I3 extends Record<string, string> {
}
type Properties =
| { [key: string]: never }
| I1
| I2
| I3
;
declare const prop1: string;
declare const prop2: string | undefined;
function F1(_arg: { props: Properties }) { }
F1({
props: {
prop1,
prop2,
},
});
function F2(_props: Properties) { }
F2({
prop1,
prop2,
});
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