revlog: clarify the comment attached to delta reuse
The previous version was a bit complicated and referred to a deprecated
configuration option.
--- a/mercurial/revlogutils/deltas.py Tue Sep 04 21:05:21 2018 +0200
+++ b/mercurial/revlogutils/deltas.py Tue Sep 04 21:28:28 2018 +0200
@@ -621,10 +621,12 @@
curr = len(revlog)
prev = curr - 1
- # This condition is true most of the time when processing
- # changegroup data into a generaldelta repo. The only time it
- # isn't true is if this is the first revision in a delta chain
- # or if ``format.generaldelta=true`` disabled ``lazydeltabase``.
+ # First we try to reuse a the delta contained in the bundle.
+ # (or from the source revlog)
+ #
+ # This logic only applies to general delta repositories and can be disabled
+ # through configuration. Disabling reuse of source delta is useful when
+ # we want to make sure we recomputed "optimal" deltas.
if cachedelta and gdelta and revlog._lazydeltabase:
# Assume what we received from the server is a good choice
# build delta will reuse the cache