ui: remove unreachable branches and function calls from write() (
issue6059)
This is at least faster than ui.write() of 4.8.2.
$ HGRCPATH=/dev/null hg files -R mozilla-central --time >/dev/null
4.8.2: time: real 2.340 secs (user 2.310+0.000 sys 0.020+0.000)
4.9rc0: time: real 2.580 secs (user 2.550+0.000 sys 0.020+0.000)
this: time: real 2.230 secs (user 2.210+0.000 sys 0.020+0.000)
Maybe the formatter should own a resolved write() function because it will
just call dest.write(msg) most of the time, but that would be too much for
stable.
Ancestors of 5
4 2 0
Ancestors of 6 and 5
4 3 2 1 0
Ancestors of 5 and 4
4 2 0
Ancestors of 7, stop at 6
6
Ancestors of 7, including revs
7 6 5 4 3 2 1 0
Ancestors of 7, 5 and 3, including revs
7 6 5 4 3 2 1 0
Descendants of 5
7 8
Descendants of 5 and 3
6 7 8
Descendants of 5 and 4
5 7 8