to have property
- <Map> [not] to have property <string> <assertion?>
Asserts that the target collection has a property name. You can extend it with another
optional assertion to test the property value:
const collection = new Map({
1: 'foo',
2: 'bar'
});
expect(collection, 'to have property', 1);
expect(collection, 'to have property', 1, 'to equal', 'foo');