Const Functionconst map = new Map([
['foo', 1],
['bar', 2],
]);
expect(map, 'to have keys satisfying', z.string()); // passes
expect(map, 'to have props satisfying', z.string()); // alias — same assertion
expect(map, 'to have fields satisfying', z.string()); // alias
expect(map, 'to contain keys satisfying', /^[a-z]+$/); // alias
Asserts that ALL keys in a Map individually satisfy the expected shape.
Uses partial/satisfy semantics — every key must match. Empty Maps pass vacuously.