view mercurial/pure/__init__.py @ 23661:dbd60f8d88d5

trydiff: use sets, not lists, for containment checks

This only has a noticeable effect on diffs touching A LOT of
files. For example, it takes

  hg diff -r FIREFOX_AURORA_30_BASE -r FIREFOX_AURORA_35_BASE

from 1m55.465s to 1m32.354s. That diff has over 50k files.