# HG changeset patch
# User Yuya Nishihara <yuya@tcha.org>
# Date 1408851353 -32400
# Node ID 3b39e1522d8f967d5f829e83d53adbc252af2e57
# Parent  dcb95aadf8505aa813039af0dfd18ad9c1de2c47
ui: add brief comment why raw_input() needs dummy ' ' prompt string

Retrieved from 17ffb30d9174.

I was about to move ' ' to label(msg + ' ', 'ui.prompt') so that subclass can
distinguish prompt output from data.  But it was not that simple.

diff -r dcb95aadf850 -r 3b39e1522d8f mercurial/ui.py
--- a/mercurial/ui.py	Sun Aug 24 23:47:26 2014 +0900
+++ b/mercurial/ui.py	Sun Aug 24 12:35:53 2014 +0900
@@ -626,6 +626,8 @@
         oldout = sys.stdout
         sys.stdin = self.fin
         sys.stdout = self.fout
+        # prompt ' ' must exist; otherwise readline may delete entire line
+        # - http://bugs.python.org/issue12833
         line = raw_input(' ')
         sys.stdin = oldin
         sys.stdout = oldout