Given two parameter arrays, compute a third tuple representing the type of args required to satisfy both of the original tuples.
Your solution should correctly handle fixed and non-fixed length arrays, optional elements and variadic elements. For example:
type Result = IntersectParameters<
[{ a: 0 }, { b: 1 }?, { c: 2 }?, ...{ d: 3 }[]],
[{ e: 4 }?, { f: 5 }?, ...{ g: 6 }[]]
>
type Expected = [
{
a: 0
e: 4
},
{
b: 1
f: 5
}?,
{
c: 2
g: 6
}?,
...{
d: 3
g: 6
}[]
]
import type { Equal, Expect } from '@type-challenges/utils'
type result1 = IntersectParameters<[], []>
type TwoEmpty = Expect<Equal<[], result1>>
type result2 = IntersectParameters<[], [string, number, ...boolean[]]>
type OneEmpty = Expect<Equal<[string, number, ...boolean[]], result2>>
type result3 = IntersectParameters<['a'], [string, number]>
type LongerParametersPreserved = Expect<Equal<['a', number], result3>>
type result4 = IntersectParameters<[unknown], []>
// Avoids evaluating unknown to {}
type UnknownPreserved = Expect<Equal<[unknown], result4>>
type result5 = IntersectParameters<[('a' | 'b' | 'c')?], [string, 1 | 2 | 3]>
type OneOptional = Expect<Equal<['a' | 'b' | 'c', 1 | 2 | 3], result5>>
type result6 = IntersectParameters<[{ a: 0 }?], [{ b: 1 }?]>
type BothOptional = Expect<Equal<[{ a: 0, b: 1 }?], result6>>
type result7 = IntersectParameters<[{ a: 0 }?], []>
type OptionalAndNotPresent = Expect<Equal<[{ a: 0 }?], result7>>
type result8 = IntersectParameters<{ a: 0 }[], { b: 1 }[]>
type TwoNonFixedLength = Expect<Equal<{ a: 0, b: 1 }[], result8>>
type result9 = IntersectParameters<[{ a: 0 }, { b: 1 }], { c: 2 }[]>
type OneNonFixedLength = Expect<
Equal<
[
{
a: 0
c: 2
},
{
b: 1
c: 2
},
...{
c: 2
}[],
],
result9
>
>
type result10 = IntersectParameters<
[{ a: 0 }, ...{ b: 1 }[]],
[{ c: 2 }, { d: 3 }]
>
type OneTrailingRest = Expect<
Equal<
[
{
a: 0
c: 2
},
{
b: 1
d: 3
},
...{
b: 1
}[],
],
result10
>
>
type result11 = IntersectParameters<
[{ a: 0 }, ...{ b: 1 }[]],
[{ c: 2 }, { d: 3 }, ...{ e: 4 }[]]
>
type TwoTrailingRest = Expect<
Equal<
[
{
a: 0
c: 2
},
{
b: 1
d: 3
},
...{
b: 1
e: 4
}[],
],
result11
>
>
type result12 = IntersectParameters<
[{ a: 0 }, { b: 1 }?, { c: 2 }?, ...{ d: 3 }[]],
[{ e: 4 }?, { f: 5 }?, ...{ g: 6 }[]]
>
type KitchenSink = Expect<
Equal<
[
{
a: 0
e: 4
},
{
b: 1
f: 5
}?,
{
c: 2
g: 6
}?,
...{
d: 3
g: 6
}[],
],
result12
>
>
type result13 = IntersectParameters<['a', 'b'], [string, ...string[]]>
type ExtraVariadicArgsPreserved = Expect<
Equal<['a', 'b', ...string[]], result13>
>