vala: Avoid critical in SourceFile.get_mapped_length()

See https://gitlab.gnome.org/GNOME/vala/issues/1330

diff --git a/vala/valasourcefile.vala b/vala/valasourcefile.vala
index 826925bfd9e3ac6943bb77be80874472a75bc01c..5f5822629d2f62e1831bd16ee73d985925858dfb 100644 (file)
--- a/vala/valasourcefile.vala
+++ b/vala/valasourcefile.vala
@@ -362,6 +362,10 @@ public class Vala.SourceFile {
                        return content.length;
                }
 
+               if (mapped_file == null) {
+                       return 0;
+               }
+
                return mapped_file.get_length ();
        }