diff --git a/mercurial/ui.py b/mercurial/ui.py
--- a/mercurial/ui.py
+++ b/mercurial/ui.py
@@ -403,7 +403,12 @@ class ui(object):
                 readline.read_history_file
             except ImportError:
                 pass
-        return raw_input(prompt)
+        line = raw_input(prompt)
+        # When stdin is in binary mode on Windows, it can cause
+        # raw_input() to emit an extra trailing carriage return
+        if os.linesep == '\r\n' and line and line[-1] == '\r':
+            line = line[:-1]
+        return line
 
     def prompt(self, msg, pat=None, default="y", matchflags=0):
         if not self.interactive: return default