config: add template support V2: - Limit escaping to plain formatting only - Use the formatter consistently (no more ui.debug) - Always include 'name' and 'value' V3: - Always convert 'value' to string (this also makes sure we handle functions) - Keep real debug message as ui.debug for now - Add additional tests. Note: I'm not quite sure about the best approach to handling the 'print the full config' case. For me, it printed the 'ui.promptecho' key at the end. I went with globs there as that at least tests the json display reliably. Example output: [ { "name": "ui.username", "source": "/home/mathias/.hgrc:2", "value": "Mathias De Maré <mathias.demare@gmail.com>" } ]

formatter: introduce isplain() to replace (the inverse of) __nonzero__() (API) V2: also remove and replace __nonzero__

diffopts: notice a negated boolean flag in diffopts This means that if you have git-diffs enabled by default (pretty common) and you hit the rare (but real) case where a git-diff breaks patch(1) or some other tool, you can easily disable it by just specifying --no-git on the command line. I feel a little bad about the isinstance() check, but some values in diffopts are not booleans and so we need to preserve false iff the flag is a boolean flag: failing to do this means we end up with empty string defaults for flags clobbering meaningful values from the [diff] section in hgrc.

flags: allow specifying --no-boolean-flag on the command line (BC) This makes it much easier to enable some anti-foot-shooting features (like update --check) by default, because now all boolean flags can be explicitly disabled on the command line without having to use HGPLAIN or similar. Flags which don't deserve this treatment can be removed from consideration by adding them to the nevernegate set in fancyopts. This doesn't make it any easier to identify when a flag is set: opts still always gets filled in, either with the user-specified flag value or with the default from the flags list in the command table. Improving that would probably clean things up a bit, but for now if you want a boolean flag and care if it was explicitly false or default false (or true, but nobody uses that functionality because before now it was nonsense) you need to use None as your default rather than True or False. This doesn't (yet) update help output, because I'm not quite sure how to do that cleanly.

revset: make sort() noop depending on ordering requirement (BC) See the previous patch for why.

revset: make reverse() noop depending on ordering requirement (BC) Because smartset.reverse() may modify the underlying subset, it should be called only if the set can define the ordering. In the following example, 'a' and 'c' is the same object, so 'b.reverse()' would reverse 'a' unexpectedly. # '0:2 & reverse(all())' <filteredset <spanset- 0:2>, # a <filteredset # b <spanset- 0:2>, # c <spanset+ 0:9>>>