swev-id: django__django-15741 fix get_format lazy literal

[casey-brooks]

Summary

• normalize `format_type` via `force_str` and treat non-identifier literals as direct values
• preserve localization module lookups for named keys, including lazy names
• add regression coverage for lazy literals in `get_format` and the date filter

Testing

• `PYTHONPATH=$PWD:$PWD/tests:$HOME/.nix-profile/lib/python3.11/site-packages DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py i18n --parallel=1`
• `PYTHONPATH=$PWD:$PWD/tests:$HOME/.nix-profile/lib/python3.11/site-packages DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py template_tests.filter_tests.test_date --parallel=1`
• `/root/.local/bin/flake8 django/utils/formats.py tests/i18n/tests.py tests/template_tests/filter_tests/test_date.py`

Reproduction

1. Install deps: `pip3 install --user --break-system-packages asgiref sqlparse pytz`
2. Set `PYTHONPATH=/workspace/django`
3. Run the script from Allow lazy parameter in django.utils.formats.get_format #551 (see description) rendering {{ d|date:_('Y-m-d') }}

Observed failure (before fix)

Traceback (most recent call last):
  File "reproduce_lazy_date.py", line 22, in <module>
    print(tmpl.render(ctx))
  File "django/template/defaultfilters.py", line 764, in date
    return formats.date_format(value, arg)
  File "django/utils/formats.py", line 128, in get_format
    val = getattr(module, format_type, None)
TypeError: attribute name must be string, not '__proxy__'

Fixes #551

[casey-brooks]

Test & Lint Summary

• PYTHONPATH=$PWD:$PWD/tests:$HOME/.nix-profile/lib/python3.11/site-packages DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py i18n --parallel=1 (217 passed, 0 failed, 74 skipped)
• PYTHONPATH=$PWD:$PWD/tests:$HOME/.nix-profile/lib/python3.11/site-packages DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py template_tests.filter_tests.test_date --parallel=1 (14 passed, 0 failed)
• /root/.local/bin/flake8 django/utils/formats.py tests/i18n/tests.py tests/template_tests/filter_tests/test_date.py (no issues)

[noa-lucent]

Looks great. Thanks for the thorough regression coverage.

[casey-brooks]

Test & Lint Summary

• `PYTHONPATH=$PWD:$PWD/tests:$(python3 -c 'import site; print(site.USER_SITE)') DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py i18n --parallel=1` (passed; 217 tests, 74 skipped)
• `PYTHONPATH=$PWD:$PWD/tests:$(python3 -c 'import site; print(site.USER_SITE)') DJANGO_SETTINGS_MODULE=tests.test_sqlite python3 tests/runtests.py template_tests.filter_tests.test_date --parallel=1` (passed; 14 tests)
• Linting not run (no code changes)

Notes: `tests/runtests.py` rejects labels ending in .py; use the dotted module path `template_tests.filter_tests.test_date` instead.

[noa-lucent]

Normalization via force_str fixes the lazy translation regression and the added identifier guard keeps module lookups intact for named settings. Regression tests cover both get_format() and the date filter path. Looks solid.

[rowan-stein]

Approving based on successful local validation and Noa’s review. Fix correctly normalizes lazy literals and preserves named setting lookups; targeted tests (i18n, template date filter) pass.

[noa-lucent]

force_str coercion keeps get_format working with lazy literals and tests cover literal & setting cases. Looks good.