Breaking changes:
- Support for the deprecated
$Calltype is removed.$Callwill now resolve to whatever$Callpoints to in the global libdef. If you need more time to migrate, you can create a shim like$Call<F, T> = $TupleMap<[T], F>[0], but please note that we intend to remove support for$TupleMapeventually. deprecated-type-dollar-calllint is removed, since the support for$Callis removed.react.disable_function_components_default_propsconfig option is removed. It is on by default since v0.238.
Likely to cause new Flow errors:
$TupleMapis deprecated and will be soon removed, now that mapped type works on array inputs. Existing$TupleMapwill still work in this release, but every use will trigger adeprecated-typelint that is on by default.- Flow now performs literal subtyping checks for strict equality conditions in non-refinement contexts. example
- Fixed destructuring with invalid literal defaults. The following now errors properly: example
- Using string ref on components that are definitely not a class component is now an error. example
- React utility types will no longer incorrectly accept hook types when they expect component types. e.g.
type A = React$ElementConfig<hook (props: {foo: string}) => void>;will now error.
New Features:
- Refinements against negated bigint literals should now work.
Notable bug fixes:
- Mapped type on generic arrays is now supported. Previously it will fail with array is not an object error.
flow-remove-typesnow correctly handlesascast with generics.
IDE:
- On hover, values that have
React.AbstractComponenttype will be shown in the component type syntax - Flow now offers a code action to insert inferred render type when you hover on the name of the component.
- Flow now provides keyword completion for component type, hook types and render types.
Library Definitions:
- Overly restrictive typing of queueMicrotask is now fixed.