Factor out inline trace code

Author: nicolasstucki

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

@@ -4,7 +4,8 @@ package transform
 import dotty.tools.dotc.ast.{Trees, tpd, untpd}
 import scala.collection.mutable
 import core._
-import typer.Checking
+import dotty.tools.dotc.typer.Checking
+import dotty.tools.dotc.typer.Inliner
 import Types._, Contexts._, Names._, Flags._, DenotTransformers._
 import SymDenotations._, StdNames._, Annotations._, Trees._, Scopes._
 import Decorators._
@@ -234,19 +235,7 @@ class PostTyper extends MacroTransform with IdentityDenotTransformer { thisPhase
               super.transform(tree1)
           }
         case Inlined(call, bindings, expansion) if !call.isEmpty =>
-          // Leave only a call trace consisting of
-          //  - a reference to the top-level class from which the call was inlined,
-          //  - the call's position
-          // in the call field of an Inlined node.
-          // The trace has enough info to completely reconstruct positions.
-          // The minimization is done for two reasons:
-          //  1. To save space (calls might contain large inline arguments, which would otherwise
-          //     be duplicated
-          //  2. To enable correct pickling (calls can share symbols with the inlined code, which
-          //     would trigger an assertion when pickling).
-          //
-          // This is the same trace that is inserted in ReifyQuotes.quotation
-          val callTrace = Ident(call.symbol.topLevelClass.typeRef).withPos(call.pos)
+          val callTrace = Inliner.inlineCallTrace(call.symbol, call.pos)
           cpy.Inlined(tree)(callTrace, transformSub(bindings), transform(expansion)(inlineContext(call)))
         case tree: Template =>
           withNoCheckNews(tree.parents.flatMap(newPart)) {

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

@@ -15,6 +15,7 @@ import typer.Implicits.SearchFailureType
 import scala.collection.mutable
 import dotty.tools.dotc.core.StdNames._
 import dotty.tools.dotc.core.quoted._
+import dotty.tools.dotc.typer.Inliner
 import dotty.tools.dotc.util.SourcePosition
 
 
@@ -375,17 +376,7 @@ class ReifyQuotes extends MacroTransformWithImplicits {
           if (level == 0 && !ctx.inRewriteMethod) {
             val body2 =
               if (body1.isType) body1
-              else {
-                // Leave only a call trace consisting of
-                //  - a reference to the top-level class from which the call was inlined,
-                //  - the call's position
-                // in the call field of an Inlined node.
-                // The trace has enough info to completely reconstruct positions.
-                //
-                // This is the same trace that is inserted in PostTyper.transform
-                val callTrace = Ident(ctx.owner.topLevelClass.typeRef).withPos(quote.pos)
-                Inlined(callTrace, Nil, body1)
-              }
+              else Inlined(Inliner.inlineCallTrace(ctx.owner, quote.pos), Nil, body1)
             pickledQuote(body2, splices, body.tpe, isType).withPos(quote.pos)
           }
           else {

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

@@ -171,6 +171,15 @@ object Inliner {
       (new Reposition).transformInline(inlined)
     }
   }
+
+  /** Leave only a call trace consisting of
+   *  - a reference to the top-level class from which the call was inlined,
+   *  - the call's position
+   *  in the call field of an Inlined node.
+   *  The trace has enough info to completely reconstruct positions.
+   */
+  def inlineCallTrace(callSym: Symbol, pos: Position)(implicit ctx: Context): Tree =
+    Ident(callSym.topLevelClass.typeRef).withPos(pos)
 }
 
 /** Produces an inlined version of `call` via its `inlined` method.