(REF) Extract LocaleTestTrait. Tighten up multilingual testing.

[totten]

Overview

This is a test-only change. Generally, it tightens up the way in which multilingual mode is enabled/disabled -- with an aim to (a) improving realism, (b) reducing duplication, (c) recovering better from test-errors.

Technical Details

There are multiple steps to setting up a valid multilingual environment, such as:

• Marking ML as enabled
• Rearranging DB columns for the original locale
• Adding DB columns for 1-2 additional locales
• Setting the list of active ML locales

Additionally, it is important to reverse these steps at the end. If there are scenarios where it doesn't cleanup (eg due to a failed test-assertion) or where it only partially cleans up

Before

Tests use some mix of:

• $this->enableMultilingual() or \CRM_Core_I18n_Schema::makeMultilingual()
• Maybe \CRM_Core_I18n_Schema::makeSinglelingua()l
• Maybe update Civi settings for ML
• Maybe add languages to ML

Some tests also don't do cleanup in a safe way (eg a failed assertion will cascade to break other tests)

If you try to run the entire phpunit --group locale, it doesn't work.

After

More consistent code-style. Either:

• Use the pair $this->enableMultilingual(['srcLocale' => 'newLocale']) and $this->disableMultilingual() (with try/finally or setup/teardown)
• Use the autoclean $cleanup = $this->useMultilingual(['srcLocale' => 'newLocale'])

If you try to run the entire phpunit --group locale, it does work.

[civibot]

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[eileenmcnaughton]

test only change - MOP