view tests/test-filelog.py.out @ 43786:421ea5772039

copies: split the combination of the copies mapping in its own function

In some case, this part take up to 95% of the copy tracing that take about a
hundred second. This poor performance comes from the fact we keep duplciating
and merging dictionary that are mostly similar.

I want to experiment with smarter native code to do this, so I need to isolate
the function first.

ERROR: FIXME: This is a known failure of filelog.size for data starting with \1\n
OK.