It was noted in #470 that make_twa_graph did not copy named
properties. Let's fix that.
* spot/twa/twa.hh, spot/twa/twa.cc (copy_named_properties_of): New
method.
* spot/twa/twagraph.hh (make_twa_graph): Add an extra argument to
call copy_named_properties_of() optionally.
* python/spot/__init__.py (twa_graph.__copy__): Use it.
* tests/python/twagraph.py: Test that.
* tests/sanity/namedprop.test: Ensure copy_named_properties_of copies
all known named properties.
Fixes#470, suggested by Cambridge Yang.
* python/spot/__init__.py (twa_graph.__copy__): Call make_twa_graph.
* tests/python/twagraph.py: Test it.
* NEWS: Mention it.
The algorithm had two problems: it was removing only useless
destination from universal destination (instead of removing the entire
edge), and it was not properly iterating over the entire reachable
automaton.
* spot/twa/twagraph.cc: Fix it.
* spot/twa/twagraph.hh: Adjust documentation.
* tests/core/alternating.test: Add more tests.
* tests/python/twagraph.py: Adjust.
* NEWS: Mention the bug.
The goal is to improve coverage stats, but I discovered two issues
while doing so.
* tests/python/twagraph.py: New test case.
* tests/Makefile.am: Add it.
* spot/twa/twagraph.hh: Add fix typos in error messages.
* python/spot/impl.i: Fix broken wrappers for state_from_number and
state_acc_sets.
