Update reflect.Symbol position API

* `Symbol.pos` return an `Option[Position]`
* Remove `Position.exists`

Author: nicolasstucki

community-build/community-projects/utest

@@ -2291,7 +2291,8 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
 
         def name: String = self.denot.name.toString
         def fullName: String = self.denot.fullName.toString
-        def pos: Position = self.sourcePos
+        def pos: Option[Position] =
+          if self.exists then Some(self.sourcePos) else None
 
         def documentation: Option[Documentation] =
           import dotc.core.Comments.CommentsContext
@@ -2566,7 +2567,6 @@ class QuotesImpl private (using val ctx: Context) extends Quotes, QuoteUnpickler
       extension (self: Position):
         def start: Int = self.start
         def end: Int = self.end
-        def exists: Boolean = self.exists
         def sourceFile: SourceFile = self.source
         def startLine: Int = self.startLine
         def endLine: Int = self.endLine

compiler/src/scala/quoted/runtime/impl/QuotesImpl.scala

@@ -3067,7 +3067,7 @@ trait Quotes { self: runtime.QuoteUnpickler & runtime.QuoteMatching =>
         def fullName: String
 
         /** The position of this symbol */
-        def pos: Position
+        def pos: Option[Position]
 
         /** The documentation for this symbol, if any */
         def documentation: Option[Documentation]
@@ -3640,9 +3640,6 @@ trait Quotes { self: runtime.QuoteUnpickler & runtime.QuoteMatching =>
         /** The end offset in the source file */
         def end: Int
 
-        /** Does this position exist */
-        def exists: Boolean
-
         /** Source file in which this position is located */
         def sourceFile: SourceFile
 

library/src/scala/quoted/Quotes.scala

@@ -41,8 +41,8 @@ trait BasicSupport:
           Map.empty
 
     def source =
-      val path = Some(sym.pos.sourceFile.jpath).filter(_ != null).map(_.toAbsolutePath).map(_.toString)
-      path.map(TastyDocumentableSource(_, sym.pos.startLine))
+      val path = Some(sym.pos.get.sourceFile.jpath).filter(_ != null).map(_.toAbsolutePath).map(_.toString)
+      path.map(TastyDocumentableSource(_, sym.pos.get.startLine))
 
     def getAnnotations(): List[Annotation] =
       sym.annotations.filterNot(_.symbol.packageName.startsWith("scala.annotation.internal")).map(parseAnnotation).reverse

scala3doc/src/dotty/dokka/tasty/BasicSupport.scala

@@ -114,7 +114,7 @@ trait ClassLikeSupport:
             extSym.symbol.normalizedName,
             extSym.tpt.dokkaType.asSignature,
             extSym.tpt.symbol.dri,
-            extSym.symbol.pos.start
+            extSym.symbol.pos.get.start
           )
           parseMethod(dd.symbol, kind = Kind.Extension(target))
         }

scala3doc/src/dotty/dokka/tasty/ClassLikeSupport.scala

@@ -41,7 +41,7 @@ trait SyntheticsSupport:
     c.flags.is(Flags.CaseAccessor) || (c.flags.is(Flags.Module) && !c.flags.is(Flags.Given))
 
   def isValidPos(pos: Position) =
-    pos.exists && pos.start != pos.end
+    pos.start != pos.end
 
   def constructorWithoutParamLists(c: ClassDef): Boolean =
     !isValidPos(c.constructor.pos)  || {