Merge pull request #8883 from dotty-staging/fix-#7442-2

Fix #7442: Only compute line numbers if the file exists

Author: nicolasstucki

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

@@ -22,7 +22,7 @@ extends interfaces.SourcePosition with Showable {
 
   def point: Int = span.point
 
-  def line: Int = if (source.exists) source.offsetToLine(point) else -1
+  def line: Int = if (source.file.exists) source.offsetToLine(point) else -1
 
   /** Extracts the lines from the underlying source file as `Array[Char]`*/
   def linesSlice: Array[Char] =
@@ -42,16 +42,16 @@ extends interfaces.SourcePosition with Showable {
   def beforeAndAfterPoint: (List[Int], List[Int]) =
     lineOffsets.partition(_ <= point)
 
-  def column: Int = if (source.exists) source.column(point) else -1
+  def column: Int = if (source.file.exists) source.column(point) else -1
 
   def start: Int = span.start
-  def startLine: Int = if (source.exists) source.offsetToLine(start) else -1
-  def startColumn: Int = if (source.exists) source.column(start) else -1
+  def startLine: Int = if (source.file.exists) source.offsetToLine(start) else -1
+  def startColumn: Int = if (source.file.exists) source.column(start) else -1
   def startColumnPadding: String = source.startColumnPadding(start)
 
   def end: Int = span.end
-  def endLine: Int = if (source.exists) source.offsetToLine(end) else -1
-  def endColumn: Int = if (source.exists) source.column(end) else -1
+  def endLine: Int = if (source.file.exists) source.offsetToLine(end) else -1
+  def endColumn: Int = if (source.file.exists) source.column(end) else -1
 
   def withOuter(outer: SourcePosition): SourcePosition = SourcePosition(source, span, outer)
   def withSpan(range: Span) = SourcePosition(source, range, outer)