text/scanner: mention package when reporting errors to stderr

Fixes #14166.

Change-Id: I325b283a1d53e73a6d862611c446820ab94a161c
Reviewed-on: https://go-review.googlesource.com/19622
Reviewed-by: Damien Neil <dneil@google.com>

diff --git a/src/text/scanner/scanner.go b/src/text/scanner/scanner.go
index 0155800f34a716d43352b3ca206c9c5f30fc69ae..dd87850fcd3538bf870cd45a1edd3ba864dc37d5 100644 (file)
--- a/src/text/scanner/scanner.go
+++ b/src/text/scanner/scanner.go
@@ -333,7 +333,7 @@ func (s *Scanner) error(msg string) {
        if !pos.IsValid() {
                pos = s.Pos()
        }
-       fmt.Fprintf(os.Stderr, "%s: %s\n", pos, msg)
+       fmt.Fprintf(os.Stderr, "text/scanner: %s: %s\n", pos, msg)
 }
 
 func (s *Scanner) isIdentRune(ch rune, i int) bool {