context: add arbitraryfilectx, which can represent files outside the workdir Move it from contrib/simplemerge so it can be re-used in the future. Differential Revision: https://phab.mercurial-scm.org/D604

simplemerge: remove unused `filtereddata` parameter Differential Revision: https://phab.mercurial-scm.org/D603

simplemerge: remove unused `repo` parameter This is now no longer used or needed thanks to the `decodeddata()` context function. Differential Revision: https://phab.mercurial-scm.org/D602

extensions: prohibit unicode defaults If the default value of an option is a unicode string (something than happen easily when using a 'from __future__ import unicode_literals'), any value passed on the command line will be ignored because the fancyopts module only checks for byte strings and not unicode strings. Changing fancyopts behavior is easy but would make assumptions on how the python3 port should be done, which is outside the scope of this patch. The chosen approach is to stop an extension from being loaded when a unicode default value is detected, with a hint for the developer.

revsetlang: remove unused functions Superseded by the _match() function.

revsetlang: match tree by helper function on optimize This should make optimize() more readable and less error-prone, but it doubles the parsing cost. (original) $ python -m timeit -n10000 -s 'from mercurial import revsetlang as L' \ 'L.optimize(L.analyze(L.parse("ancestors(x) and not ancestors(y)")))' 10000 loops, best of 3: 79.3 usec per loop (this patch) $ python -m timeit -n10000 -s 'from mercurial import revsetlang as L' \ 'L._treecache.clear(); \ L.optimize(L.analyze(L.parse("ancestors(x) and not ancestors(y)")))' 10000 loops, best of 3: 201 usec per loop