NonEmptyArray#filter returns wrong type

[pedrodim]

🐛 Bug report

Current Behavior

type Values = "A" | "B";
const values: NonEmptyArray<Values> = ["A", "B"];
const filterValues = (value: Values): value is "B" => value === "B";

const filteredValues = nonEmptyArray.filter(filterValues)(values);

filteredValues is Option<NonEmptyArray<Values>>

Expected behavior

filteredValues is Option<NonEmptyArray<"B">>

Your environment

Which versions of fp-ts are affected by this issue? Did this work in previous versions of fp-ts?

Software	Version(s)
fp-ts	2.9.3
TypeScript	4.1.3

[samhh]

I can repro:

declare const p: (x: unknown) => x is string;
declare const xs: NonEmptyArray<unknown>;
const ys = NEA.filter(p)(xs);

[gcanti]

@pedrodim @samhh thanks, patch released.