tests: add tests and document expectations from visit_children_set in rust
The tests this patch are adding have the form of formal spec in
invariants::visit_children_set::holds,
and then a series of checks that all examples must satisfy this
formal spec.
I tried to make the spec consistent with how this function is used
and how it was originally conceived. This is in conflict with how it's
documented in Rust. Some of the implementations also fail to implement
this spec, which leads to bugs, in particular when complicated patterns
are used with `hg status`.
import os
import sys
import unittest
def main(modulename):
'''run the tests found in module, printing nothing when all tests pass'''
module = sys.modules[modulename]
suite = unittest.defaultTestLoader.loadTestsFromModule(module)
results = unittest.TestResult()
suite.run(results)
if results.errors or results.failures:
for tc, exc in results.errors:
print('ERROR:', tc)
print()
sys.stdout.write(exc)
for tc, exc in results.failures:
print('FAIL:', tc)
print()
sys.stdout.write(exc)
sys.exit(1)
if os.environ.get('SILENT_BE_NOISY'):
main = unittest.main