Simplify tracking of inlined positions

This makes the workaround for the missing JSR-45 support slightly less precise.

Author: nicolasstucki

compiler/src/dotty/tools/dotc/ast/Trees.scala

@@ -1242,11 +1242,9 @@ object Trees {
     protected def skipTransform(tree: Tree)(using Context): Boolean = false
 
     /** For untyped trees, this is just the identity.
-     *  For typed trees, a context derived form `ctx` that records `call` as the
-     *  innermost enclosing call for which the inlined version is currently
-     *  processed.
+     *  For typed trees, this record the position of an enclosing inlined positions
      */
-    protected def inlineContext(call: Tree)(using Context): Context = ctx
+    protected def inlineContext(pos: SrcPos)(using Context): Context = ctx
 
     abstract class TreeMap(val cpy: TreeCopier = inst.cpy) { self =>
       def transform(tree: Tree)(using Context): Tree = {

compiler/src/dotty/tools/dotc/ast/tpd.scala

@@ -7,7 +7,7 @@ import typer.ProtoTypes
 import transform.SymUtils._
 import transform.TypeUtils._
 import core._
-import util.Spans._, util.SourcePosition, Types._, Contexts._, Constants._, Names._, Flags._, NameOps._
+import util.Spans._, util.SrcPos, Types._, Contexts._, Constants._, Names._, Flags._, NameOps._
 import Symbols._, StdNames._, Annotations._, Trees._, Symbols._
 import Decorators._, DenotTransformers._
 import collection.{immutable, mutable}
@@ -1232,37 +1232,27 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
   }
 
   /** A key to be used in a context property that tracks enclosing inlined calls */
-  private val InlinedCalls = Property.Key[List[SourcePosition]]()
+  private val InlinedCalls = Property.Key[List[SrcPos]]()
 
   /** A key to be used in a context property that tracks the number of inlined trees */
   private val InlinedTrees = Property.Key[Counter]()
   final class Counter {
     var count: Int = 0
   }
 
-  /** Record an enclosing inlined call.
-   *  EmptyTree calls (for parameters) cancel the next-enclosing call in the list instead of being added to it.
-   *  We assume parameters are never nested inside parameters.
-   */
-  override def inlineContext(call: Tree)(using Context): Context = {
+  /** Record an enclosing inlined positions. */
+  override def inlineContext(pos: SrcPos)(using Context): Context = {
     // We assume enclosingInlineds is already normalized, and only process the new call with the head.
     val oldIC = enclosingInlineds
-
-    val newIC =
-      if call.isEmpty then
-        oldIC match
-          case t1 :: ts2 => ts2
-          case _ => oldIC
-      else
-        call.sourcePos :: oldIC
+    val newIC = pos :: oldIC
 
     val ctx1 = ctx.fresh.setProperty(InlinedCalls, newIC)
     if oldIC.isEmpty then ctx1.setProperty(InlinedTrees, new Counter) else ctx1
   }
 
   /** All enclosing calls that are currently inlined, from innermost to outermost.
    */
-  def enclosingInlineds(using Context): List[SourcePosition] =
+  def enclosingInlineds(using Context): List[SrcPos] =
     ctx.property(InlinedCalls).getOrElse(Nil)
 
   /** Record inlined trees */

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

@@ -115,8 +115,8 @@ object report:
     if (ctx.settings.Ydebug.value) warning(msg, pos)
 
   private def addInlineds(pos: SrcPos)(using Context): SourcePosition =
-    def recur(pos: SourcePosition, inlineds: List[SourcePosition]): SourcePosition = inlineds match
-      case inlined :: inlineds1 => pos.withOuter(recur(inlined.sourcePos, inlineds1))
+    def recur(pos: SourcePosition, inlineds: List[SrcPos]): SourcePosition = inlineds match
+      case inlined :: inlineds1 => pos.sourcePos.withOuter(recur(inlined.sourcePos, inlineds1))
       case Nil => pos
     recur(pos.sourcePos, tpd.enclosingInlineds)
 

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

@@ -1431,7 +1431,7 @@ class Inliner(call: tpd.Tree, rhsToInline: tpd.Tree)(using Context) {
       if suspendable then
         ctx.compilationUnit.suspend() // this throws a SuspendException
 
-    val evaluatedSplice = inContext(quoted.MacroExpansion.context(inlinedFrom)) {
+    val evaluatedSplice = inContext(quoted.MacroExpansion.context(inlinedFrom.sourcePos)) {
       Splicer.splice(body, inlinedFrom, MacroClassLoader.fromContext)
     }
     val inlinedNormailizer = new TreeMap {

tests/run/i4947b.check

@@ -4,8 +4,8 @@ main1: Test$.main(Test_2.scala:4)
 main2: Test$.main(Test_2.scala:5)
 track: Test$.main(Test_2.scala:7)
 track: Test$.main(Test_2.scala:7)
-track: Test$.main(Test_2.scala:8)
-track: Test$.main(Test_2.scala:8)
+track: Test$.main(Test_2.scala:7)
+track: Test$.main(Test_2.scala:7)
 main3: Test$.main(Test_2.scala:9)
 main4: Test$.main(Test_2.scala:10)
 track (i = 0): Test$.main(Test_2.scala:13)
@@ -15,22 +15,22 @@ track: Test$.main(Test_2.scala:13)
 fact: Test$.main(Test_2.scala:13)
 track (i = 2): Test$.main(Test_2.scala:14)
 track (i = 2): Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-fact: Test$.main(Test_2.scala:14)
+track: Test$.main(Test_2.scala:13)
+track: Test$.main(Test_2.scala:13)
+fact: Test$.main(Test_2.scala:13)
 main1 (i = -1): Test$.main(Test_2.scala:15)
 main2 (i = -1): Test$.main(Test_2.scala:16)
-track (i = 1): Test$.main(Test_2.scala:14)
-track (i = 1): Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-fact: Test$.main(Test_2.scala:14)
+track (i = 1): Test$.main(Test_2.scala:13)
+track (i = 1): Test$.main(Test_2.scala:13)
+track: Test$.main(Test_2.scala:13)
+track: Test$.main(Test_2.scala:13)
+fact: Test$.main(Test_2.scala:13)
 main1 (i = -1): Test$.main(Test_2.scala:15)
 main2 (i = -1): Test$.main(Test_2.scala:16)
-track (i = 0): Test$.main(Test_2.scala:14)
-track (i = 0): Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-track: Test$.main(Test_2.scala:14)
-fact: Test$.main(Test_2.scala:14)
+track (i = 0): Test$.main(Test_2.scala:13)
+track (i = 0): Test$.main(Test_2.scala:13)
+track: Test$.main(Test_2.scala:13)
+track: Test$.main(Test_2.scala:13)
+fact: Test$.main(Test_2.scala:13)
 main1 (i = -1): Test$.main(Test_2.scala:15)
 main2 (i = -1): Test$.main(Test_2.scala:16)