The churn extension's alias support does not work properly when an alias has leading whitespace. I have a contributor who has accidentally committed as both "x@y.com" and " x@y.com". Adding the entry " x@y.com = x@y.com" to the aliases list does not combine the contributions for churn output: separate output is produced for "x@y.com" and " x@y.com".
it's true that we probably dont care about spaces around emails. I pushed a fix in stable as 2245fcd0e160
Fixed by http://selenic.com/repo/hg/rev/2506658c3927 Nicolas Dumazet <nicdumz.commits@gmail.com> churn: ignore trailing and leading spaces (issue2546) (please test the fix)
--- Bug imported by bugzilla@serpentine.com 2012-05-12 09:15 EDT --- This bug was previously known as _bug_ 2546 at http://mercurial.selenic.com/bts/issue2546