oldObj: "baz",
			schema: withRule(stringType, `
				!oldSelf.hasValue() || self == "bar"
			`),
		},
		{
			name:   "integer",
			obj:    1,
			oldObj: 2,
			schema: withRule(integerType, `
				!oldSelf.hasValue() || self == 1
			`),
		},
		{
			name:   "number",
			obj:    1.1,
			oldObj: 2.2,
			schema: withRule(numberType, `