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tests/cases/compiler/four.ts(11,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/four.ts(15,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/one.ts(11,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/one.ts(15,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/three.ts(11,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/three.ts(15,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/two.ts(11,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
tests/cases/compiler/two.ts(15,11): error TS2540: Cannot assign to 'a' because it is a read-only property.
==== tests/cases/compiler/one.ts (2 errors) ====
export {};
// When the non-readonly type is declared first, the unioned type of `three` in `doSomething` is never treated as readonly
const two: { a: string } = { a: 'two' };
const one: { readonly a: string } = { a: 'one' };
function doSomething(condition: boolean) {
// when `one` comes first in the conditional check, the return type of `doSomething` is inferred as `a` is readonly, but `a` is
// only treated as readonly (i.e. it will produce a diagnostic if you try to assign to it) based on the order of declarations of `one` and `two` above
const three = (condition) ? one : two;
three.a = 'foo';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
// the inferred (displayed?) type of `a` also depends on the order of the condition above. When `one` comes first, the displayed type is `any`
// when `two` comes first, the displayed type is `string`, but the diagnostic will always correctly find that it's string
three.a = 'foo2';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
return three;
}
==== tests/cases/compiler/two.ts (2 errors) ====
export {};
// When the non-readonly type is declared first, the unioned type of `three` in `doSomething` is never treated as readonly
const two: { a: string } = { a: 'two' };
const one: { readonly a: string } = { a: 'one' };
function doSomething(condition: boolean) {
// when `two` comes first in the conditional check, the return type of `doSomething` is inferred as not readonly but produces the same diagnostics as above
// based on the declaration order of `one` and `two`
const three = (condition) ? two : one;
three.a = 'foo';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
// the inferred (displayed?) type of `a` also depends on the order of the condition above. When `one` comes first, the displayed type is `any`
// when `two` comes first, the displayed type is `string`, but the diagnostic will always correctly find that it's string
three.a = 'foo2';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
return three;
}
==== tests/cases/compiler/three.ts (2 errors) ====
export {};
// When the readonly type is declared first, the unioned type of `three` in `doSomething` is always treated as readonly by the compiler
const one: { readonly a: string } = { a: 'one' };
const two: { a: string } = { a: 'two' };
function doSomething(condition: boolean) {
// when `one` comes first in the conditional check, the return type of `doSomething` is inferred as `a` is readonly, but `a` is
// only treated as readonly (i.e. it will produce a diagnostic if you try to assign to it) based on the order of declarations of `one` and `two` above
const three = (condition) ? one : two;
three.a = 'foo';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
// the inferred (displayed?) type of `a` also depends on the order of the condition above. When `one` comes first, the displayed type is `any`
// when `two` comes first, the displayed type is `string`, but the diagnostic will always correctly find that it's string
three.a = 'foo2';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
return three;
}
==== tests/cases/compiler/four.ts (2 errors) ====
export {};
// When the readonly type is declared first, the unioned type of `three` in `doSomething` is always treated as readonly by the compiler
const one: { readonly a: string } = { a: 'one' };
const two: { a: string } = { a: 'two' };
function doSomething(condition: boolean) {
// when `two` comes first in the conditional check, the return type of `doSomething` is inferred as not readonly but produces the same diagnostics as above
// based on the declaration order of `one` and `two`
const three = (condition) ? two : one;
three.a = 'foo';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
// the inferred (displayed?) type of `a` also depends on the order of the condition above. When `one` comes first, the displayed type is `any`
// when `two` comes first, the displayed type is `string`, but the diagnostic will always correctly find that it's string
three.a = 'foo2';
~
!!! error TS2540: Cannot assign to 'a' because it is a read-only property.
return three;
}
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