diff --git a/src/testdir/runtest.vim b/src/testdir/runtest.vim
index 2eabb1a..6c42616 100644
--- a/src/testdir/runtest.vim
+++ b/src/testdir/runtest.vim
@@ -364,6 +364,13 @@
   call add(s:messages, message)
   let s:done += 1
 
+  " May be editing some buffer, wipe it out.  Then we may end up in another
+  " buffer, continue until we end up in an empty no-name buffer without a swap
+  " file.
+  while bufname() != '' || execute('swapname') !~ 'No swap file'
+    bwipe!
+  endwhile
+
   " Check if the test has left any swap files behind.  Delete them before
   " running tests again, they might interfere.
   let swapfiles = s:GetSwapFileList()