1 files changed, 13 insertions, 0 deletions
diff --git a/tests/stdlib/tstreams.nim b/tests/stdlib/tstreams.nim
index 354bdf60f..6979bae38 100644
--- a/tests/stdlib/tstreams.nim
+++ b/tests/stdlib/tstreams.nim
@@ -6,6 +6,7 @@ Nice name: Arne
 fs is: nil
 
 threw exception
+_heh_
 '''
   nimout: '''
 I
@@ -49,3 +50,15 @@ block tstreams3:
     for line in s.lines:
       echo line
     s.close
+
+# bug #12410
+
+var a = newStringStream "hehohihahuhyh"
+a.readDataStrImpl = nil
+
+var buffer = "_ooo_"
+
+doAssert a.readDataStr(buffer, 1..3) == 3
+
+echo buffer
+