[HOLD for payment 2023-11-21] Unified testing utilities for mocks using a fake data generation library

[mountiny]

Problem

Mocking data with confidence is crucial when developing tests, especially for an offline-first data-driven app. What I saw myself was a lack of predefined mocking strategies, which combined with the poor type-safety led me to a lot of errors and frustration. Each test file (when written by different people over time) had to reinvent the wheel when it comes to working with reports, reportActions, policies and so on.

Solution

By introducing a fake data library (my pick was ngneat/falso - it’s more lightweight and composable than the popular faker module) as a dev dependency we can unify our mocks across the whole project and improve the DX of our teams when testing.

The example below shows whole entities being mocked, but with composition we can also generate useful partials.

[melvin-bot]

Triggered auto assignment to @lschurr (NewFeature), see https://stackoverflowteams.com/c/expensify/questions/14418#:~:text=BugZero%20process%20steps%20for%20feature%20requests for more details.

[mountiny]

@adhorodyski can you please comment on this issue?

@lschurr nothing required for this one right now

[adhorodyski]

@mountiny sure thing, I'd like to work on this.

[melvin-bot]

The solution for this issue has been 🚀 deployed to production 🚀 in version 1.3.98-5 and is now subject to a 7-day regression period 📆. Here is the list of pull requests that resolve this issue:

• [NoQA] chore(tests): unified utilities for mocking collections #30833

If no regressions arise, payment will be issued on 2023-11-21. 🎊

After the hold period is over and BZ checklist items are completed, please complete any of the applicable payments for this issue, and check them off once done.

• External issue reporter
• Contributor that fixed the issue
• Contributor+ that helped on the issue and/or PR

For reference, here are some details about the assignees on this issue:

• @adhorodyski does not require payment (Contractor)

[melvin-bot]

BugZero Checklist: The PR adding this new feature has been merged! The following checklist (instructions) will need to be completed before the issue can be closed:

• [@adhorodyski] Please propose regression test steps to ensure the new feature will work correctly on production in further releases.
• [@lschurr] Link the GH issue for creating/updating the regression test once above steps have been agreed upon.

[mountiny]

This is completed, nothing to pay out