Re: Deprecate ReflectionParameter::isArray() and friends

On Tue, Feb 25, 2020 at 10:33 AM Nikita Popov <nikita.ppv@gmail.com> wrote: > I've put up https://github.com/php/php-src/pull/5209 to > deprecate the > following reflection methods: > > * ReflectionParameter::isArray() > * ReflectionParameter::isCallable() > * ReflectionParameter::getClass() > > These APIs have been superseded by ReflectionParameter::getType() since PHP > 7.0. Types introduced since that time are not available through the old > APIs. The behavior of these methods becomes increasingly confusing with > additional type system extensions. With the addition of union types in PHP > 8: > > * isArray() will return true if the type is array or ?array, but not any > other union type. > * getClass() will return a ReflectionClass for T|int etc, as long as the > union only contains a single type. T1|T2 will return null. > > There is really no reasonable behavior for these methods in the presence of > union types; we should start phasing them out. > > One point I'm not sure about is whether we want to deprecate > ReflectionParameter::allowsNull() as well. Logically this method belongs on > ReflectionType (and does in fact exist there), but the way it is formulated > is still compatible with union types, so leaving it alone is a possibility. > Why do you say there's no "reasonable behavior ... in the presence of union types"? To me, the following seem like reasonable interpretations in a post-union-type world: ::isArray() returns true IIF is_array(type) === true for at least one type in the parameter ::isCallable() returns true IIF is_callable(type) === true for at least one type in the parameter ::getClass() returns null IIF class_exists(type) === false for all types in the parameter; returns ReflectionClass IIF class_exists(type) for exactly one type in the parameter; throws \TypeError otherwise