Yup Files

Type casts no longer "succeed without fail". For instance boolean will throw if a cast produces an invalid type, instead of quietly coercing to false. By default cast will now throw in these situations, passing assert: false to cast options will disable this behavior and the value returned will be the invalid value (NaN, InvalidDate, null) or the original value if no good invalid value exists in the language

number().cast('foo', { assert: false }) // -> NaN
bool().cast('foo', { assert: false })   // -> 'foo'