TypeScript/tests/cases/conformance/expressions/propertyAccess/propertyAccessWidening.ts
Anders Hejlsberg 9d2a2c9634 Add tests
2019-06-06 13:33:36 -07:00

22 lines
730 B
TypeScript

// @strict: true
// Repro from #31762
function g1(headerNames: any) {
let t = [{ hasLineBreak: false, cells: [] }];
const table = [{cells: headerNames }].concat(t);
}
function g2(headerNames: any) {
let t = [{ hasLineBreak: false, cells: [] }];
const table = [{cells: headerNames }]["concat"](t);
}
// Object in property or element access is widened when target of assignment
function foo(options?: { a: string, b: number }) {
let x1 = (options || {}).a; // Object type not widened
let x2 = (options || {})["a"]; // Object type not widened
(options || {}).a = 1; // Object type widened, error
(options || {})["a"] = 1; // Object type widened, error
}