Add regression tests

Author: nicolasstucki

tests/run-macros/string-context-implicits.check

@@ -0,0 +1,4 @@
+Int(1) Str(abc)
+Int(1) Str(abc)
+xyz
+Int(1) Str(xyz)

tests/run-macros/string-context-implicits/Macro_1.scala

@@ -0,0 +1,31 @@
+import scala.quoted._
+import scala.quoted.matching._
+
+inline def (sc: StringContext) showMe(args: =>Any*): String = ${ showMeExpr('sc, 'args) }
+
+private def showMeExpr(sc: Expr[StringContext], argsExpr: Expr[Seq[Any]])(given qctx: QuoteContext): Expr[String] = {
+  argsExpr match {
+    case ExprSeq(argExprs) =>
+      val argShowedExprs = argExprs.map {
+        case '{ $arg: $tp } =>
+          val showTp = '[Show[$tp]]
+          summonExpr(given showTp, summon[QuoteContext]) match {
+            case Some(showExpr) => '{ $showExpr.show($arg) }
+            case None => qctx.error(s"could not find implicit for ${showTp.show}", arg); '{???}
+          }
+      }
+      val newArgsExpr = Expr.ofSeq(argShowedExprs)
+      '{ $sc.s($newArgsExpr: _*) }
+    case _ =>
+      // `new StringContext(...).showMeExpr(args: _*)` not an explicit `showMeExpr"..."`
+      qctx.error(s"Args must be explicit", argsExpr)
+      '{???}
+  }
+}
+
+trait Show[-T] {
+  def show(x: T): String
+}
+
+given Show[Int] = x => s"Int($x)"
+given Show[String] = x => s"Str($x)"

tests/run-macros/string-context-implicits/Test_2.scala

@@ -0,0 +1,9 @@
+object Test {
+
+  def main(args: Array[String]): Unit = {
+    println(showMe"${1: Int} ${"abc": String}")
+    println(showMe"${1} ${"abc"}")
+    println(showMe"${1} ${println("xyz"); "xyz"}")
+  }
+
+}

tests/run/string-context-implicits-with-conversion.check

@@ -0,0 +1,4 @@
+Int(1) Str(abc)
+Int(1) Str(abc)
+xyz
+Int(1) Str(xyz)

tests/run/string-context-implicits-with-conversion.scala

@@ -0,0 +1,24 @@
+
+object Lib {
+  def (sc: StringContext) showMe(args: Showed*): String = sc.s(args: _*)
+
+  opaque type Showed = String
+
+  given [T](given show: Show[T]): Conversion[T, Showed] = x => show(x)
+
+  trait Show[T] {
+    def apply(x: T): String
+  }
+
+  given Show[Int] = x => s"Int($x)"
+  given Show[String] = x => s"Str($x)"
+}
+object Test {
+  import Lib._
+  def main(args: Array[String]): Unit = {
+    println(showMe"${1: Int} ${"abc": String}")
+    println(showMe"${1} ${"abc"}")
+    println(showMe"${1} ${println("xyz"); "xyz"}")
+  }
+
+}