Newly added fncache entries were not added to the in-memory cache,
making it possible for 'hg convert' to cause duplicates in
.hg/store/fncache.
Duplicates in the fncache file are harmless, but excessive numbers
of duplicates from large converted repositories may slow down
execution speed considerably.
- in parseargs(), check that --with-hg value is valid
- add handy --local option for "--with-hg=../hg"
- ensure that we always set PATH and PYTHONPATH (not just
when doing a temporary install)
- override any existing PYTHONPATH, so test success does not
depend on whatever happens to be in the caller's environment
- give tests a little more control by exporting $PYTHON to the
environment; needed by test-convert and test-mergetool when
they run hg with a stripped-down $PATH
Also, add a big comment explaining all the corner cases to test for the
next person who tries to modify this script.
