tests: add check to make sure summary works on Python 2

color: replace str() with pycompat.bytestr()

diff: slice over bytes to make sure conditions work normally Both of this are part of generating `hg diff` on python 3.

minirst: remove redundant _admonitions set As Yuya pointed out during a review a month ago, _admonitions and _admonitiontitles are largely redundant. With the last commit, they are exactly redundant. So, remove _admonitions and use _admonitiontitles.keys() instead.

minirst: remove "admonition" from _admonitions The "admonition" rst primitive is split into "specific" admonitions ("attention," "caution," etc) and the "generic" admonition ("admonition"). For more, see http://docutils.sourceforge.net/docs/ref/rst/directives.html#admonitions The _admonitions set and keys of the _admonitiontitles dict overlap exactly except _admonitions has an "admonition" entry. Nowhere in Mercurial is the "admonition" admonition directive used. Even if it were, it doesn't have a title, so it wouldn't be rendered correctly. So, let's remove "admonition" from the set of recognized admonition directives.

minirst: reindent _admonitiontitles I don't like the verical indent. While I was here, I cleaned up some whitespace and added a trailing comma on the last element.

tags: extract filenode filtering into its own function We'll also need to reuse this logic so we extract it into its own function. We document some of the logic in the process.