run-tests: factor out _escapepath

tests/run-tests.py

@@ -724,16 +724,19 b' class Test(unittest.TestCase):'
             (br'(?m)^(saved backup bundle to .*\.hg)( \(glob\))?$',
              br'\1 (glob)'),
             ]
+        r.append((self._escapepath(self._testtmp), b'$TESTTMP'))
 
+        return r
+
+    def _escapepath(self, p):
         if os.name == 'nt':
-            r.append(
+            return (
                 (b''.join(c.isalpha() and b'[%s%s]' % (c.lower(), c.upper()) or
                     c in b'/\\' and br'[/\\]' or c.isdigit() and c or b'\\' + c
-                    for c in self._testtmp), b'$TESTTMP'))
+                    for c in p))
+            )
         else:
-            r.append((re.escape(self._testtmp), b'$TESTTMP'))
-
-        return r
+            return re.escape(p)
 
     def _getenv(self):
         """Obtain environment variables to use during test execution."""