[PATCH 7 of 7] bundle2: force the first char of parameter to be an letter

[pierre-yves.david at ens-lyon.org]

# HG changeset patch
# User Pierre-Yves David <pierre-yves.david at fb.com>
# Date 1395194168 25200
#      Tue Mar 18 18:56:08 2014 -0700
# Node ID eec1f3d69dcd9f8656776045e36f277ec5ebd8f9
# Parent  ca51ee1121790c891e1f98cd18d8b664f131ea31
bundle2: force the first char of parameter to be an letter.

We need a case sensitive character to convey mandatory/advisory parameter
semantic in a later patches.

diff --git a/mercurial/bundle2.py b/mercurial/bundle2.py
--- a/mercurial/bundle2.py
+++ b/mercurial/bundle2.py
@@ -45,10 +45,14 @@ Binary format is as follow
   The blob contains a space separated list of parameters. parameter with value
   are stored in the form `<name>=<value>`. Both name and value are urlquoted.
 
   Empty name are obviously forbidden.
 
+  Name MUST start with a letter. This first character has to be capitalizable.
+  The capitalisation of the first letter will be used to know if an option is
+  advisory or mandatory. This is not implemented yet.
+
   Stream parameters use a simple textual format for two main reasons:
 
   - Stream level parameters should remains simple and we want to discourage any
     crazy usage.
   - Textual data allow easy human inspection of a the bundle2 header in case of
@@ -70,10 +74,11 @@ Binary format is as follow
 """
 
 import util
 import struct
 import urllib
+import string
 
 import changegroup
 from i18n import _
 
 _pack = struct.pack
@@ -98,10 +103,12 @@ class bundle20(object):
 
     def addparam(self, name, value=None):
         """add a stream level parameter"""
         if not name:
             raise ValueError('empty parameter name')
+        if name[0] not in string.letters:
+            raise ValueError('non letter first character: %r' % name)
         self._params.append((name, value))
 
     def getchunks(self):
         yield _magicstring
         param = self._paramchunk()
diff --git a/tests/test-bundle2.t b/tests/test-bundle2.t
--- a/tests/test-bundle2.t
+++ b/tests/test-bundle2.t
@@ -160,5 +160,11 @@ Test buggy input
 empty parameter name
 
   $ hg bundle2 --param '' --quiet
   abort: empty parameter name
   [255]
+
+bad parameter name
+
+  $ hg bundle2 --param 42babar
+  abort: non letter first character: '42babar'
+  [255]