Typer regression in multiple Open CB projects

[WojciechMazur]

Compiler version

3.3.1-RC1-bin-20230504-0e00420-NIGHTLY

Needs minimization based on Open Community Build projects

Project	Version	Build URL	Notes
dwickern/scala-nameof	4.0.0	Open CB logs	typer, mismatch
scalikejdbc/scalikejdbc	4.0.0	Open CB logs	typer, mismatch, macro
scalikejdbc/scalikejdbc-async	0.18.0	Open CB logs	typer, mismatch, macro
bitlap/scalikejdbc-helper	0.2.3 -> 0.2.6	Open CB logs	typer, mismatch, macro

Output

Example failure from dwickern/scala-nameof

Error:  -- [E007] Type Mismatch Error: /build/repo/src/test/scala/com/github/dwickern/macros/NameOfTest.scala:54:11 
Error:  54 |    nameOf(func1 _) should equal ("func1")
Error:     |           ^^^^^
Error:     |           Found:    Int => String
Error:     |           Required: T => Any

Expectation

[WojciechMazur]

Reproducer for dwickern/scala-nameof

#macros.scala
trait NameOf:
  transparent inline def nameOf(inline expr: Any): String = ${NameOfImpl.nameOf('expr)}
  transparent inline def nameOf[T](inline expr: T => Any): String = ${NameOfImpl.nameOf('expr)}
object NameOf extends NameOf

import scala.compiletime.*

import scala.annotation.tailrec
import scala.quoted.*

object NameOfImpl {
  def nameOf(expr: Expr[Any])(using Quotes): Expr[String] = {
    import quotes.reflect.*
    @tailrec def extract(tree: Tree): String = tree match {
      case Ident(name) => name
      case Select(_, name) => name
      case Block(List(stmt), term) => extract(stmt)
      case DefDef("$anonfun", _, _, Some(term)) => extract(term)
      case Block(_, term) => extract(term)
      case Apply(term, _) if term.symbol.fullName != "<special-ops>.throw" => extract(term)
      case TypeApply(term, _) => extract(term)
      case Inlined(_, _, term) => extract(term)
      case Typed(term, _) => extract(term)
      case _ => throw new MatchError(s"Unsupported expression: ${expr.show}")
    }
    val name = extract(expr.asTerm)
    Expr(name)
  }
}

# test.scala

import NameOf._
def test() = 
    def func1(x: Int): String = ???
    val funcVal = func1 _
    assert(nameOf(funcVal) == "funcVal")
    assert(nameOf(func1 _) == "func1")

Output

-- [E007] Type Mismatch Error: /workspace/bisect/test.scala:7:18 ---------------
7 |    assert(nameOf(funcVal) == "funcVal")
  |                  ^^^^^^^
  |                  Found:    (funcVal : Int => String)
  |                  Required: T => Any
  |
  | longer explanation available when compiling with `-explain`
-- [E007] Type Mismatch Error: /workspace/bisect/test.scala:8:18 ---------------
8 |    assert(nameOf(func1 _) == "func1")
  |                  ^^^^^
  |                  Found:    Int => String
  |                  Required: T => Any
  |
  | longer explanation available when compiling with `-explain`

Last good release: 3.3.1-RC1-bin-20230501-1aa3372-NIGHTLY
First bad release: 3.3.1-RC1-bin-20230502-dee0065-NIGHTLY

Further bisect based commit was not possible due to problems with very strange compile errors not related to that issue, run following command to see the list of potential commits:

git log 1aa3372..dee0065

@nicolasstucki @smarter I can see that most of potential commits that could introduce that regression was commit by you. Can you please take a look at that code snippet?

[WojciechMazur]

The reproducer for scalikejdbc/scalikejdbc, remaining projects are probably related to same issue

// macro.scala
import scala.quoted.*

object SelectDynamicMacroImpl {
  def selectImpl[E: Type](
    ref: Expr[SQLSyntaxProvider[_]],
    name: Expr[String]
  )(using Quotes): Expr[SQLSyntax] = '{SQLSyntax("foo")}
}

// test.scala
import scala.language.dynamics

trait SQLSyntaxProvider[A] extends Dynamic{
  def field(name: String): SQLSyntax = ???
 
  inline def selectDynamic(inline name: String): SQLSyntax = 
  select[A](this, name)

  inline def select[E](ref: SQLSyntaxProvider[A], inline name: String): SQLSyntax = 
    ${ SelectDynamicMacroImpl.selectImpl[E]('ref, 'name) }
}

class SQLSyntax(value: String)
trait SQLSyntaxSupport[A]
case class ColumnSQLSyntaxProvider[S <: SQLSyntaxSupport[A], A](support: S) extends SQLSyntaxProvider[A]

case class Account(id: Long, name: String)
object Account extends SQLSyntaxSupport[Account]

def Test() =
  val p = ColumnSQLSyntaxProvider[Account.type, Account](Account)
  assert(p.name == SQLSyntax("name"))

Output

Compiling project (Scala 3.3.1-RC1-bin-20230510-d6c643c-NIGHTLY, JVM)
[error] ./test.scala:22:10
[error] Found:    (SQLSyntaxProvider_this : (p : ColumnSQLSyntaxProvider[Account.type, Account]))
[error] Required: SQLSyntaxProvider[A]
[error]   assert(p.name == SQLSyntax("name"))
[error]       

Both reproducers have in common usage of quotes and started to fail in the same commit range

[WojciechMazur]

Bisect points to 5ae7861

[nicolasstucki]

Minimized

import scala.quoted.*
def impl[E: Type](ref: Expr[Foo[_]])(using Quotes): Expr[Unit] = '{ }

trait Foo[A]:
  inline def foo(): Unit = bar[this.type](this)
  inline def bar[E](ref: Foo[A]): Unit = ${ impl[E]('ref) }
def test(p: Foo[Int]) = p.foo()

[nicolasstucki]

Other minimization

import scala.quoted.*
inline def foo[T](expr: T => Any): Unit = ${impl('expr)}
def impl(expr: Expr[Any])(using Quotes): Expr[Unit] = '{}

def test(f: Int => Any) = foo(f)