diff --git a/tests/run-tests.py b/tests/run-tests.py
index 1ab30e9ba0fceb15736ad226ff701325e9682ec9_dGVzdHMvcnVuLXRlc3RzLnB5..05925bb5f95afc9699739325f45e9f6614bcaebf_dGVzdHMvcnVuLXRlc3RzLnB5 100755
--- a/tests/run-tests.py
+++ b/tests/run-tests.py
@@ -882,8 +882,8 @@
                     postout.append('  ' + el)
                 else:
                     if self.NEEDESCAPE(lout):
-                        lout = TTest.stringescape('%s (esc)\n' %
-                                                  lout.rstrip('\n'))
+                        lout = TTest._stringescape('%s (esc)\n' %
+                                                   lout.rstrip('\n'))
                     postout.append('  ' + lout) # Let diff deal with it.
                     if r != '': # If line failed.
                         warnonly = 3 # for sure not