test(fxa-auth-server): migrate DB, Redis & storage tests from Mocha PART 3

[vbudhram]

Because

• The fxa-auth-server is migrating from Mocha/Chai to Jest as part of FXA-12564
• 8 test files in test/local/ covering DB, Redis, bounces, account lifecycle, and reminder modules needed migration
• Some tests classified as "local" actually require real Redis, warranting reclassification as integration tests

This pull request

• Adds 5 co-located unit tests in lib/:
  • lib/bounces.spec.ts (from test/local/bounces.js)
  • lib/account-events.spec.ts (from test/local/account-events.js)
  • lib/account-delete.spec.ts (from test/local/account-delete.js)
  • lib/db.spec.ts (from test/local/db.js)
  • lib/inactive-accounts/index.spec.ts (from test/local/inactive-accounts/index.js)
• Adds 3 integration tests in test/remote/ (require real Redis):
  • test/remote/redis.in.spec.ts (from test/local/redis.js)
  • test/remote/cad-reminders.in.spec.ts (from test/local/cad-reminders.js)
  • test/remote/subscription-account-reminders.in.spec.ts (from test/local/subscription-account-reminders.js)
• Converts proxyquire to jest.mock() factories, chai assertions to expect(), forEach-wrapped it() to it.each()
• Fixes Redis contention in reminder tests by flushing stale keys in beforeEach and properly awaiting close() in afterEach

Issue

Closes: https://mozilla-hub.atlassian.net/browse/FXA-12564

Checklist

• My commit is GPG signed
• Tests pass locally (if applicable)
• Documentation updated (if applicable)
• RTL rendering verified (if UI changed)

Other Information

Stability: Unit tests (300 total suite) passed 5/5 runs. Integration reminder tests passed 5/5 runs after the Redis contention fix.

Note: Original Mocha test files in test/local/ are intentionally kept in place. Deletion will be handled in a follow-up PR once the migration is validated in CI.

Test Parity

All 167 runtime tests have full 1:1 parity — no tests added, dropped, or changed in behavior.

Mocha Source	Jest Target	Type	Mocha Tests	Jest Tests	Parity
test/local/bounces.js	lib/bounces.spec.ts	Unit	8	8	FULL
test/local/account-events.js	lib/account-events.spec.ts	Unit	6	6	FULL
test/local/account-delete.js	lib/account-delete.spec.ts	Unit	15	15	FULL
test/local/db.js	lib/db.spec.ts	Unit	25	25	FULL
test/local/inactive-accounts/index.js	lib/inactive-accounts/index.spec.ts	Unit	10	10	FULL
test/local/redis.js	test/remote/redis.in.spec.ts	Integration	43	43	FULL
test/local/cad-reminders.js	test/remote/cad-reminders.in.spec.ts	Integration	17	17	FULL
test/local/subscription-account-reminders.js	test/remote/subscription-account-reminders.in.spec.ts	Integration	43	43	FULL
Total			167	167	FULL

[vbudhram]

These PRs are pretty big to be reviewed manually. Here are some steps/prompts that you can use to verify the parity between them.

• Compare the assertions between the mocha and jest tests
• Compare the number of tests
• Run 5 times to see if anything is flaky
• Ask to find any gaps in the migrated tests with their originals

[nshirley]

question, non-blocking: I noticed between this PR and others that there appears a lot of similar container setup, did you find that was the case and there's a lot of duplicate setup, or are they all just slightly different?

[vbudhram]

They were sligthly different mocks for each test. I didn't want to refactor it out since it would change unrelated files. We can probably re-evaluate in the follow up issue.

[nshirley]

The original tests had an assertion that the log was passed to the redis constructor

        assert.equal(args[1], log, 'redisPool was passed log');

Probably safe to omit it, just wanted to flag!

[nshirley]

Should these be unit or integration since they're creating db with each test? I guess I would classify anything that creates a db instance and connects to it an integration test

[vbudhram]

Fair question! I can make these integration tests

[vbudhram]

@nshirley I was confused by function createDB, that gets mocked by below so no real db connection is made.