Conversion does not work well with Tuple 23 and above.

[takapi327]

Hi there 👋

Type Mismatch Error occurs when using Conversion with more than 23 Tuples.

※ The "cats.Id" part can be anything.

Compiler version

3.3.0

Minimized code

import scala.deriving.Mirror
import cats.Id

def test[P <: Product](using mirror: Mirror.ProductOf[P])(tuples: Tuple.Map[mirror.MirroredElemTypes, Id]): Tuple.Map[mirror.MirroredElemTypes, Id] = tuples

given Conversion[Id[2], Id[Seq[2]]] = v => Seq(v)

Successful Patterns

case class Test(p1: 1, p2: Seq[2], p3: 3, p4: 4, p5: 5, p6: 6, p7: 7, p8: 8, p9: 9, p10: 10, p11: 11, p12: 12, p13: 13, p14: 14, p15: 15, p16: 16, p17: 17, p18: 18, p19: 19, p20: 20, p21: 21, p22: 22)

test[Test](Id[1](1), Id[2](2), Id[3](3), Id[4](4), Id[5](5), Id[6](6), Id[7](7), Id[8](8), Id[9](9), Id[10](10), Id[11](11), Id[12](12), Id[13](13), Id[14](14), Id[15](15), Id[16](16), Id[17](17), Id[18](18), Id[19](19), Id[20](20), Id[21](21), Id[22](22))

Failure Patterns

case class Test(p1: 1, p2: Seq[2], p3: 3, p4: 4, p5: 5, p6: 6, p7: 7, p8: 8, p9: 9, p10: 10, p11: 11, p12: 12, p13: 13, p14: 14, p15: 15, p16: 16, p17: 17, p18: 18, p19: 19, p20: 20, p21: 21, p22: 22, p23: 23)

test[Test](Id[1](1), Id[2](2), Id[3](3), Id[4](4), Id[5](5), Id[6](6), Id[7](7), Id[8](8), Id[9](9), Id[10](10), Id[11](11), Id[12](12), Id[13](13), Id[14](14), Id[15](15), Id[16](16), Id[17](17), Id[18](18), Id[19](19), Id[20](20), Id[21](21), Id[22](22), Id[23](23))

Output

Successful Patterns

val res6: (cats.Id[1], cats.Id[Seq[2]], cats.Id[3], cats.Id[4], cats.Id[5],
  cats.Id[6], cats.Id[7], cats.Id[8], cats.Id[9], cats.Id[10], cats.Id[11],
  cats.Id[12], cats.Id[13], cats.Id[14], cats.Id[15], cats.Id[16], cats.Id[17],
  cats.Id[18], cats.Id[19], cats.Id[20], cats.Id[21], cats.Id[22]) = (1,List(2),3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22)

Failure Patterns

-- [E007] Type Mismatch Error: -------------------------------------------------
1 |test[Test](Id[1](1), Id[2](2), Id[3](3), Id[4](4), Id[5](5), Id[6](6), Id[7](7), Id[8](8), Id[9](9), Id[10](10), Id[11](11), Id[12](12), Id[13](13), Id[14](14), Id[15](15), Id[16](16), Id[17](17), Id[18](18), Id[19](19), Id[20](20), Id[21](21), Id[22](22), Id[23](23))
  |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |Found:    (Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int,
  |  Int, Int, Int, Int, Int, Int, Int, Int)
  |Required: Tuple.Map[
  |  ((1 : Int), Seq[(2 : Int)], (3 : Int), (4 : Int), (5 : Int), (6 : Int),
  |    (7 : Int), (8 : Int), (9 : Int), (10 : Int), (11 : Int), (12 : Int),
  |    (13 : Int), (14 : Int), (15 : Int), (16 : Int), (17 : Int), (18 : Int),
  |    (19 : Int), (20 : Int), (21 : Int), (22 : Int), (23 : Int)),
  |cats.Id]
  |
  | longer explanation available when compiling with `-explain`
1 error found

Expectation

Since Scala3 no longer has a Tuple limit, we hope that more than 23 Tuples will be successful without any problems.

[jchyb]

More self-contained minimization:

import scala.deriving.Mirror

type Id[A] = A
object Id:
  def apply[A](a: A): Id[A] = a

def test[P <: Product](using mirror: Mirror.ProductOf[P])(tuples: Tuple.Map[mirror.MirroredElemTypes, Id]): Tuple.Map[mirror.MirroredElemTypes, Id] = tuples

def main() =
  case class Test(p1: 1, p2: 2, p3: 3, p4: 4, p5: 5, p6: 6, p7: 7, p8: 8, p9: 9, p10: 10, p11: 11, p12: 12, p13: 13, p14: 14, p15: 15, p16: 16, p17: 17, p18: 18, p19: 19, p20: 20, p21: 21, p22: 22, p23: 23)
  test[Test](Id[1](1), Id[2](2), Id[3](3), Id[4](4), Id[5](5), Id[6](6), Id[7](7), Id[8](8), Id[9](9), Id[10](10), Id[11](11), Id[12](12), Id[13](13), Id[14](14), Id[15](15), Id[16](16), Id[17](17), Id[18](18), Id[19](19), Id[20](20), Id[21](21), Id[22](22), Id[23](23))