Fix scala#6538: Make interfaces.SourcePosition resilient to missing s…

…ources

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

@@ -22,8 +22,7 @@ extends interfaces.SourcePosition with Showable {
 
   def point: Int = span.point
 
-  /** The line of the position, starting at 0 */
-  def line: Int = source.offsetToLine(point)
+  def line: Int = if (source.exists) source.offsetToLine(point) else -1
 
   /** Extracts the lines from the underlying source file as `Array[Char]`*/
   def linesSlice: Array[Char] =
@@ -43,17 +42,16 @@ extends interfaces.SourcePosition with Showable {
   def beforeAndAfterPoint: (List[Int], List[Int]) =
     lineOffsets.partition(_ <= point)
 
-  /** The column of the position, starting at 0 */
-  def column: Int = source.column(point)
+  def column: Int = if (source.exists) source.column(point) else -1
 
   def start: Int = span.start
-  def startLine: Int = source.offsetToLine(start)
-  def startColumn: Int = source.column(start)
+  def startLine: Int = if (source.exists) source.offsetToLine(start) else -1
+  def startColumn: Int = if (source.exists) source.column(start) else -1
   def startColumnPadding: String = source.startColumnPadding(start)
 
   def end: Int = span.end
-  def endLine: Int = source.offsetToLine(end)
-  def endColumn: Int = source.column(end)
+  def endLine: Int = if (source.exists) source.offsetToLine(end) else -1
+  def endColumn: Int = if (source.exists) source.column(end) else -1
 
   def withOuter(outer: SourcePosition): SourcePosition = SourcePosition(source, span, outer)
   def withSpan(range: Span) = SourcePosition(source, range, outer)

interfaces/src/dotty/tools/dotc/interfaces/SourcePosition.java

@@ -17,23 +17,23 @@ public interface SourcePosition {
 
   /** @return Offset to the point */
   int point();
-  /** @return Line number of the point, starting at 0 */
+  /** @return Line number of the point, starting at 0. -1 if the line cannot be computed */
   int line();
-  /** @return Column number of the point, starting at 0 */
+  /** @return Column number of the point, starting at 0. -1 if the column cannot be computed */
   int column();
 
   /** @return Offset to the range start */
   int start();
-  /** @return Line number of the range start, starting at 0 */
+  /** @return Line number of the range start, starting at 0. -1 if the line cannot be computed */
   int startLine();
-  /** @return Column number of the range start, starting at 0 */
+  /** @return Column number of the range start, starting at 0. -1 if the column cannot be computed */
   int startColumn();
 
   /** @return Offset to the range end */
   int end();
-  /** @return Line number of the range end, starting at 0 */
+  /** @return Line number of the range end, starting at 0. -1 if the line cannot be computed */
   int endLine();
-  /** @return Column number of the range end, starting at 0 */
+  /** @return Column number of the range end, starting at 0. -1 if the column cannot be computed */
   int endColumn();
 
   /** The source file corresponding to this position.

sbt-bridge/src/xsbt/DelegatingReporter.java

@@ -86,7 +86,9 @@ public Optional<String> sourcePath() {
           return Optional.ofNullable(src.file().path());
         }
         public Optional<Integer> line() {
-          return Optional.of(pos.line());
+          int line = pos.line();
+          if (line == -1) return Optional.empty();
+          else return Optional.of(line);
         }
         public String lineContent() {
           String line = pos.lineContent();