let run-tests run optional code coverage tests.
to enable, set env var TEST_COVERAGE to non-empty string. run-tests will
print report after running.
after coverage run, file tests/.coverage will contain coverage data. use
tests/coverage.py to get more info, like annotated source code.
removing b
this update spans a branch affecting the following files:
b
aborting update spanning branches!
(use 'hg merge' to merge across branches or 'hg update -C' to lose changes)