Add type class power macro regression test

Author: nicolasstucki

tests/pos-macros/power-macro-2/Macro_1.scala

@@ -0,0 +1,22 @@
+
+import scala.quoted.*
+
+import math.Numeric.Implicits.infixNumericOps
+
+inline def power[Num](x: Num, inline n: Int)(using num: Numeric[Num]) = ${powerCode('x, 'n)(using 'num)}
+
+private def powerCode[Num: Type](x: Expr[Num], n: Expr[Int])(using Expr[Numeric[Num]])(using Quotes): Expr[Num] =
+  powerCode(x, n.valueOrAbort)
+
+private def powerCode[Num: Type](x: Expr[Num], n: Int)(using num: Expr[Numeric[Num]])(using Quotes): Expr[Num] =
+  if (n == 0) '{ $num.one }
+  else if (n % 2 == 0) '{
+    given Numeric[Num] = $num
+    val y = $x * $x
+    ${ powerCode('y, n / 2) }
+  }
+  else '{
+    given Numeric[Num] = $num
+    $x * ${powerCode(x, n - 1)}
+  }
+

tests/pos-macros/power-macro-2/Test_2.scala

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+def test(x: Int) = power(x, 5)
+def test(x: Double) = power(x, 5)