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=== tests/cases/conformance/expressions/propertyAccess/propertyAccessWidening.ts ===
// Repro from #31762
function g1(headerNames: any) {
>g1 : (headerNames: any) => void
>headerNames : any
let t = [{ hasLineBreak: false, cells: [] }];
>t : { hasLineBreak: boolean; cells: never[]; }[]
>[{ hasLineBreak: false, cells: [] }] : { hasLineBreak: boolean; cells: never[]; }[]
>{ hasLineBreak: false, cells: [] } : { hasLineBreak: boolean; cells: never[]; }
>hasLineBreak : boolean
>false : false
>cells : never[]
>[] : never[]
const table = [{cells: headerNames }].concat(t);
>table : { cells: any; }[]
>[{cells: headerNames }].concat(t) : { cells: any; }[]
>[{cells: headerNames }].concat : { (...items: ConcatArray<{ cells: any; }>[]): { cells: any; }[]; (...items: ({ cells: any; } | ConcatArray<{ cells: any; }>)[]): { cells: any; }[]; }
>[{cells: headerNames }] : { cells: any; }[]
>{cells: headerNames } : { cells: any; }
>cells : any
>headerNames : any
>concat : { (...items: ConcatArray<{ cells: any; }>[]): { cells: any; }[]; (...items: ({ cells: any; } | ConcatArray<{ cells: any; }>)[]): { cells: any; }[]; }
>t : { hasLineBreak: boolean; cells: never[]; }[]
}
function g2(headerNames: any) {
>g2 : (headerNames: any) => void
>headerNames : any
let t = [{ hasLineBreak: false, cells: [] }];
>t : { hasLineBreak: boolean; cells: never[]; }[]
>[{ hasLineBreak: false, cells: [] }] : { hasLineBreak: boolean; cells: never[]; }[]
>{ hasLineBreak: false, cells: [] } : { hasLineBreak: boolean; cells: never[]; }
>hasLineBreak : boolean
>false : false
>cells : never[]
>[] : never[]
const table = [{cells: headerNames }]["concat"](t);
>table : { cells: any; }[]
>[{cells: headerNames }]["concat"](t) : { cells: any; }[]
>[{cells: headerNames }]["concat"] : { (...items: ConcatArray<{ cells: any; }>[]): { cells: any; }[]; (...items: ({ cells: any; } | ConcatArray<{ cells: any; }>)[]): { cells: any; }[]; }
>[{cells: headerNames }] : { cells: any; }[]
>{cells: headerNames } : { cells: any; }
>cells : any
>headerNames : any
>"concat" : "concat"
>t : { hasLineBreak: boolean; cells: never[]; }[]
}
// Object in property or element access is widened when target of assignment
function foo(options?: { a: string, b: number }) {
>foo : (options?: { a: string; b: number;}) => void
>options : { a: string; b: number; } | undefined
>a : string
>b : number
let x1 = (options || {}).a; // Object type not widened
>x1 : string | undefined
>(options || {}).a : string | undefined
>(options || {}) : { a: string; b: number; } | {}
>options || {} : { a: string; b: number; } | {}
>options : { a: string; b: number; } | undefined
>{} : {}
>a : string | undefined
let x2 = (options || {})["a"]; // Object type not widened
>x2 : string | undefined
>(options || {})["a"] : string | undefined
>(options || {}) : { a: string; b: number; } | {}
>options || {} : { a: string; b: number; } | {}
>options : { a: string; b: number; } | undefined
>{} : {}
>"a" : "a"
(options || {}).a = 1; // Object type widened, error
>(options || {}).a = 1 : 1
>(options || {}).a : any
>(options || {}) : { a: string; b: number; } | {}
>options || {} : { a: string; b: number; } | {}
>options : { a: string; b: number; } | undefined
>{} : {}
>a : any
>1 : 1
(options || {})["a"] = 1; // Object type widened, error
>(options || {})["a"] = 1 : 1
>(options || {})["a"] : any
>(options || {}) : { a: string; b: number; } | {}
>options || {} : { a: string; b: number; } | {}
>options : { a: string; b: number; } | undefined
>{} : {}
>"a" : "a"
>1 : 1
}
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