Enrico/bug context

[em1208]

• Closes # (insert issue number)
• Executed pre-commit run --all-files with no errors
• The change is fully covered by automated unit tests
• Documented in docs/ as appropriate
• Added an entry to the CHANGES file

I fixed a bug related to unit conversion when using context. Without the single line change in pint/facets/context/registry.py calling compatible_units fails with KeyError: <UnitsContainer({'[mass]': 1, '[time]': -1})>.

I hope this change can be merged and released soon!

[codspeed-hq]

CodSpeed Performance Report

Merging #1944 will degrade performances by 27.45%

_{Comparing em1208:enrico/bug-context (6d25704) with master (8f12bb9)}

Summary

❌ 9 regressions
✅ 428 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	master	em1208:enrico/bug-context	Change
❌	test_parse_units[False-angstrom]	50.7 µs	66.7 µs	-24.02%
❌	test_parse_units[False-meter]	52.2 µs	68.6 µs	-23.87%
❌	test_parse_units[False-minute]	51.4 µs	67.8 µs	-24.14%
❌	test_parse_units[False-second]	50.7 µs	66.7 µs	-24.02%
❌	test_parse_units[True-angstrom]	51.6 µs	64.7 µs	-20.26%
❌	test_to_units_container_detached[False-angstrom]	45.2 µs	62 µs	-27.1%
❌	test_to_units_container_detached[False-meter]	45.4 µs	62.2 µs	-27.03%
❌	test_to_units_container_registry[False-angstrom]	45.1 µs	61.6 µs	-26.75%
❌	test_to_units_container_registry[False-meter]	45.2 µs	62.3 µs	-27.45%

[hgrecco]

If I understand correctly, the problem is that after adding definitions, the cache is not rebuilt. Right? I think I have a better solution. I will try to put it in another PR

[em1208]

@hgrecco Yes, the problem is that when the context is enabled the cache should be rebuilt otherwise currently an exception is raised.

[hgrecco]

@em1208 This is the proposal #1779