Fix #6150: Emit error when calling Scala 2 macro

Author: nicolasstucki

compiler/src/dotty/tools/dotc/profile/Profiler.scala

@@ -228,7 +228,7 @@ object ConsoleProfileReporter extends ProfileReporter {
   }
 
   override def reportGc(data: GcEventData): Unit = {
-    println(f"Profiler GC reported ${data.gcEndMillis - data.gcStartMillis}ms")
+    println(s"Profiler GC reported ${data.gcEndMillis - data.gcStartMillis}ms")
   }
 }
 

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -2753,6 +2753,10 @@ class Typer extends Namer
         tree.tpe <:< wildApprox(pt)
         readaptSimplified(Inliner.inlineCall(tree, pt))
       }
+      else if (tree.symbol.is(Macro, butNot = Inline)) {
+        ctx.error("Scala 2 macro cannot be used in Dotty. See http://dotty.epfl.ch/docs/reference/dropped-features/macros.html", tree.sourcePos)
+        tree
+      }
       else if (tree.tpe <:< pt) {
         if (pt.hasAnnotation(defn.InlineParamAnnot))
           checkInlineConformant(tree, isFinal = false, "argument to inline parameter")

compiler/test/dotty/tools/backend/jvm/AsmNode.scala

@@ -15,8 +15,8 @@ sealed trait AsmNode[+T] {
   def attrs: List[Attribute]
   def visibleAnnotations: List[AnnotationNode]
   def invisibleAnnotations: List[AnnotationNode]
-  def characteristics = f"$name%15s $desc%-30s$accessString$sigString"
-  def erasedCharacteristics = f"$name%15s $desc%-30s$accessString"
+  def characteristics = "%15s %-30s%s%s".format(name, desc, accessString, sigString)
+  def erasedCharacteristics = "%15s %-30s%s".format(name, desc, accessString)
 
   private def accessString     = if (access == 0) "" else " " + Modifier.toString(access)
   private def sigString        = if (signature == null) "" else " " + signature

project/Build.scala

@@ -568,6 +568,12 @@ object Build {
             IO.delete(trgDir)
           IO.createDirectory(trgDir)
           IO.unzip(scalaJSIRSourcesJar, trgDir)
+
+          // Remove f interpolator macro call to avoid its expansion while compiling the compiler and the implementation of the f macro
+          val utilsFile = trgDir / "org/scalajs/ir/Utils.scala"
+          val patchedSource = IO.read(utilsFile).replace("""f"\\u$c%04x"""", """"\\u%04x".format(c)""")
+          IO.write(utilsFile, patchedSource)
+
           (trgDir ** "*.scala").get.toSet
         } (Set(scalaJSIRSourcesJar)).toSeq
       }.taskValue,