Fix compiling quote in file with no splices

Author: nicolasstucki

compiler/src/dotty/tools/dotc/CompilationUnit.scala

@@ -8,6 +8,7 @@ import dotty.tools.dotc.ast.tpd.{ Tree, TreeTraverser }
 import dotty.tools.dotc.core.Contexts.Context
 import dotty.tools.dotc.core.SymDenotations.ClassDenotation
 import dotty.tools.dotc.core.Symbols._
+import dotty.tools.dotc.transform.SymUtils._
 
 class CompilationUnit(val source: SourceFile) {
 
@@ -35,13 +36,21 @@ object CompilationUnit {
     assert(!unpickled.isEmpty, unpickled)
     val unit1 = new CompilationUnit(new SourceFile(clsd.symbol.associatedFile, Seq()))
     unit1.tpdTree = unpickled
-    if (forceTrees)
+    if (forceTrees) {
+      val force = new Force
       force.traverse(unit1.tpdTree)
+      unit1.containsQuotesOrSplices = force.containsQuotes
+    }
     unit1
   }
 
   /** Force the tree to be loaded */
-  private object force extends TreeTraverser {
-    def traverse(tree: Tree)(implicit ctx: Context): Unit = traverseChildren(tree)
+  private class Force extends TreeTraverser {
+    var containsQuotes = false
+    def traverse(tree: Tree)(implicit ctx: Context): Unit = {
+      if (tree.symbol.isQuote)
+        containsQuotes = true
+      traverseChildren(tree)
+    }
   }
 }

compiler/src/dotty/tools/dotc/transform/PostTyper.scala

@@ -180,6 +180,7 @@ class PostTyper extends MacroTransform with IdentityDenotTransformer { thisPhase
     override def transform(tree: Tree)(implicit ctx: Context): Tree =
       try tree match {
         case tree: Ident if !tree.isType =>
+          handleMeta(tree.symbol)
           tree.tpe match {
             case tpe: ThisType => This(tpe.cls).withPos(tree.pos)
             case _ => tree

tests/pos/quote-no-splices.scala

@@ -0,0 +1,9 @@
+class Foo {
+  def foo: Unit = {
+    val expr ='{
+      val a = 3
+      println("foo")
+      2 + a
+    }
+  }
+}