Fix filename completion if path starts with ~

doc/changelog.txt

@@ -3,6 +3,7 @@
 Fixes:
 - checking: Fix typo calling get_temp_file() function.
   Closes: SF bug #3196917
+- cmdline: Fix filename completion if path starts with ~
 
 Changes:
 - checking: Use HTTP GET requests to work around buggy IIS servers

linkchecker

@@ -517,7 +517,8 @@ if has_optcomplete:
         else:
             listdir = cwd
         return [os.path.join(startdir, f)
-                for f in os.listdir(listdir) if f.startswith(lhs)]
+                for f in os.listdir(os.path.expanduser(listdir))
+                if f.startswith(lhs)]
     optcomplete.autocomplete(optparser, arg_completer=FileCompleter)