Suggestion: Object.getOwnPropertyNames and Object.keys should return type with keyof #15570

const




    
 Suits = {
    clubs: { toString: () => '\u2663' },
    diamonds: { toString: () => '\u2666' },
    hearts: { toString: () => '\u2665' },
    spades: { toString: () => '\u2660' }
type Suit = keyof typeof Suits;
const Ranks = {
    ace: { valueOf: () => 1, toString: () => 'A' },
    deuce: { valueOf: () => 2, toString: () => '2' },
    three: { valueOf: () => 3, toString: () => '3' },
    four: { valueOf: () => 4, toString: () => '4' },
    five: { valueOf: () => 5, toString: () => '5' },
    six: { valueOf: () => 6, toString: () => '6' },
    seven: { valueOf: () => 7, toString: () => '7' },
    eight: { valueOf: () => 8, toString: () => '8' },
    nine: { valueOf: () => 9, toString: () => '9' },
    ten: { valueOf: () => 10, toString: () => 'T' },
    jack: { valueOf: () => 11, toString: () => 'J' },
    queen: { valueOf: () => 12, toString: () => 'Q' },
    king: { valueOf: () => 13, toString: () => 'K' }
type Rank = keyof typeof Ranks;
type Card<R extends Rank, S extends Suit> = { rank: R, suit: S }
let deck = Object
    .keys(Suits)
    .reduce<Card<Rank, Suit>[]>((cards, suit) =>
        cards.concat(Object
            .keys(Ranks)
            .map(rank => ({
                rank: <Rank>rank, // Should be inferred instead
                suit: <Suit>suit  // Should be inferred instead
            }))
    []);