Address review: avoiding unnecessary using Context

Author: liufengyun

compiler/src/dotty/tools/dotc/core/tasty/PositionPickler.scala

@@ -16,12 +16,17 @@ import Contexts._, Symbols._, Annotations._, Decorators._
 import collection.mutable
 import util.Spans._
 
+import scala.annotation.constructorOnly
+
 class PositionPickler(
     pickler: TastyPickler,
     addrOfTree: PositionPickler.TreeToAddr,
-    treeAnnots: untpd.MemberDef => List[tpd.Tree])(using Context) {
+    treeAnnots: untpd.MemberDef => List[tpd.Tree])(using @constructorOnly ctx: Context) {
 
   import ast.tpd._
+
+  val relativePathReference = ctx.settings.sourceroot.value
+
   val buf: TastyBuffer = new TastyBuffer(5000)
   pickler.newSection(PositionsSection, buf)
 
@@ -67,9 +72,9 @@ class PositionPickler(
         // specialization.
     }
 
-    def pickleSource(source: SourceFile)(using Context): Unit = {
+    def pickleSource(source: SourceFile): Unit = {
       buf.writeInt(SOURCE)
-      val relativePath = SourceFile.relativePath(source)
+      val relativePath = SourceFile.relativePath(source, relativePathReference)
       buf.writeInt(pickler.nameBuffer.nameIndex(relativePath.toTermName).index)
     }
 
@@ -94,7 +99,7 @@ class PositionPickler(
       case _ => false
     }
 
-    def traverse(x: Any, current: SourceFile)(using Context): Unit = x match {
+    def traverse(x: Any, current: SourceFile): Unit = x match {
       case x: untpd.Tree =>
         if (x.span.exists) {
           val addr = addrOfTree(x)

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

@@ -335,7 +335,8 @@ class PostTyper extends MacroTransform with IdentityDenotTransformer { thisPhase
                && ctx.compilationUnit.source.exists
                && sym != defn.SourceFileAnnot
             then
-              val relativePath = util.SourceFile.relativePath(ctx.compilationUnit.source)
+              val reference = ctx.settings.sourceroot.value
+              val relativePath = util.SourceFile.relativePath(ctx.compilationUnit.source, reference)
               sym.addAnnotation(Annotation.makeSourceFile(relativePath))
           else (tree.rhs, sym.info) match
             case (rhs: LambdaTypeTree, bounds: TypeBounds) =>

compiler/src/dotty/tools/dotc/util/SourceFile.scala

@@ -210,9 +210,9 @@ object SourceFile {
     src._maybeInComplete = maybeIncomplete
     src
 
-  def relativePath(source: SourceFile)(using Context): String = {
+  def relativePath(source: SourceFile, reference: String): String = {
     def sourcerootPath =
-      java.nio.file.Paths.get(ctx.settings.sourceroot.value)
+      java.nio.file.Paths.get(reference)
       .toAbsolutePath
       .normalize
     val file = source.file