encoding: add an encoding-aware lower function

add: notify when adding a file that would cause a case-folding collision On a case-sensitive file system, files can be added with names that differ only in case (a "case collision"). This would cause an error on case-insensitive filesystems. A warning or error is now given for such collisions, depending on the value of ui.portablefilenames ('warn', 'abort', or 'ignore'): $ touch file File $ hg add --config ui.portablefilenames=abort File abort: possible case-folding collision for File $ hg add File warning: possible case-folding collision for File

scmutil: refactor ui.portablefilenames processing The ui.portablefilenames config handling is generally useful for notifying the user of various portability problems.

pure bdiff: don't use a generator Generators are slow, and currently defeat the PyPy JIT.

pure mpatch: avoid using list.insert(0, ...) In Python lists are implemented as arrays with overallocation. As a result, list.insert(0, ...) is O(n), whereas list.append() has an amortised running time of O(1). Reversing the internal representation of the list should cause a slight speedup for pure Python builds.

remove unused imports and variables

Zeroconf: catch both ValueError and KeyError in get() This prevents a traceback during discovery of available hosts.

run-tests: print a new line before writing the diff

revsets: add a last function last(set, n) = reverser(limit(reverse(set), n))

bundle: more comments about the different header types, remove useless if