Merge pull request #3852 from dotty-staging/fix-interpreting-typed-trees

Fix interpretation of Typed trees

Author: liufengyun

compiler/src/dotty/tools/dotc/interpreter/Interpreter.scala

@@ -111,10 +111,13 @@ class Interpreter(implicit ctx: Context) {
         val env2 = bindings.foldLeft(env)((acc, x) => interpretStat(x, acc))
         interpretTreeImpl(expansion, env2)
 
+      case Typed(expr, _) =>
+        interpretTreeImpl(expr, env)
+
       case _ =>
         // TODO Add more precise descriptions of why it could not be interpreted.
         // This should be done after the full interpreter is implemented.
-        throw new StopInterpretation(s"Could not interpret ${tree.show}\n${tree}", tree.pos)
+        throw new StopInterpretation(s"Could not interpret ${tree.show}. Consider extracting logic into a helper def.", tree.pos)
     }
   }
 

tests/run/quote-splice-interpret-1.check

@@ -0,0 +1,2 @@
+true
+false

tests/run/quote-splice-interpret-1/Macro_1.scala

@@ -0,0 +1,14 @@
+import dotty.tools.dotc.ast.Trees.Import
+
+import scala.quoted._
+object Macros {
+  sealed trait Nat
+  case object Z extends Nat
+  case class S[N <: Nat]() extends Nat
+
+  inline def isZero(inline n: Int): Boolean = ~{
+    if (n == 0) (true: Expr[Boolean])
+    else (false: Expr[Boolean])
+  }
+
+}

tests/run/quote-splice-interpret-1/Test_2.scala

@@ -0,0 +1,7 @@
+import Macros._
+object Test {
+  def main(args: Array[String]): Unit = {
+    println(isZero(0))
+    println(isZero(1))
+  }
+}