graphlog: apply file filters --patch/--stat output When passing --patch/--stat, file filters have to be applied to generate the correct diff or stat output: - Without --follow, the static match object can be reused - With --follow, the files displayed at revision X are the ancestors of selected files at parent revision. To do this, we reproduce the ancestry calculations done by --follow, lazily. test-glog.t changes show that --patch output is not satisfying because renames are reported as copies. This can probably be fixed by: - Without --follow: compute files to display, look for renames sources and extend the matcher to include them. - With --follow: detect .path() transitions between parent/child filectx, filter them using the linked changectx .removed() field and extend fcache with them.

context: add followfirst arg to filectx and workingfilectx When _followfirst() revset was introduced it seemed to be the sole user of such an argument, so filectx.ancestors() was duplicated and modified instead. It now appears this argument could be used when computing the set of files to be considered when --patch or --stat are passed along with --follow FILE.

graphlog: fix --removed "hg log --removed FILE" does not return changesets where FILE was removed, but ones where FILE was changed and possibly removed. The flag is really here to disable walkchangerevs() fast path, which cannot see file removals by scanning filelogs.

test-glog: rewrite more tests using testlog() function

match: consider filesets as "anypats" Matt suggested this on IRC, I do not think the choice is obvious, but this one makes things simpler because while filesets are turned into a list of files into the match objects, it would more be difficult to tell invalid files passed in pats from those expanded from filesets.

graphlog: evaluate FILE/-I/-X filesets on the working dir This subtlety is not documented yet but: - pats/--include/--exclude filesets are evaluated against the working directory - --rev filesets are reevaluated against every revisions

graphlog: implement --copies

test-check-code-hg: skip test if not in a working dir (issue3248).

copies: use ctx.dirs() for directory rename detection

copies: fix mergecopies doc mapping direction