Merge pull request #162 from luoliyan/master

Handle invalid delimiters more gracefully

aqt/importing.py

@@ -112,6 +112,11 @@ you can enter it here. Use \\t to represent tab."""),
                 self, help="importing") or "\t"
         str = str.replace("\\t", "\t")
         str = str.encode("ascii")
+        if len(str) > 1:
+            showWarning(_(
+                "Multi-character separators are not supported. "
+                "Please enter one character only."))
+            return
         self.hideMapping()
         def updateDelim():
             self.importer.delimiter = str