tests/blacklists/README

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.

Put here definitions of blacklists for run-tests.py

Create a file per blacklist. Each file should list the names of tests that you
want to be skipped.
File names are meant to be used as targets for run-tests.py --blacklist
option.
Lines starting with # are ignored. White spaces are stripped.

e.g. if you create a blacklist/example file containing:
 test-hgrc
 # some comment
 test-help
then calling "run-tests.py --blacklist blacklists/example" will exclude
test-hgrc and test-help from the list of tests to run.