feat: support aliased t functions from useTranslation hooks

[masnormen]

In my codebase, there are a lot of cases where we use aliased t function to differentiate between 2 useTranslation hook calls referring to different namespaces. (bcs of typescript perf issue as described in: i18next/i18next#2198)

function MyComponent() {
  const { t: tCommon } = useTranslation('common');
  const { t: tProfile } = useTranslation('profile');

  return <p>{tCommon('key1')} {tProfile('key2')}</p>;
}

The keys could be detected if we add tCommon and tProfile into the tFunctionNames options. Unfortunately, it can't detect the namespace and keyprefixes correctly. The t function call is detected as an "orphan" function call (as in, not originating from the hook).

Because the way useTranslationHook extractor works is using a hardcoded "t", therefore the plugin couldn't identify if the t function has been aliased.

babel-plugin-i18next-extract/src/extractors/useTranslationHook.ts

Line 59 in 7cc5b80

const tBinding = id.scope.bindings['t'];

This PR enables the plugin to detect if the t function has been aliased.

This PR also includes fixes and tests from #276 as the changed code is related. Credit to @guiedugt. Sorry for just copy pasting. I want to include their commits so they're included as Author in this PR, but I couldn't find a way to merge/include changes from a different fork repo.

This project will be very useful for us the moment this PR being merged. Thank you for creating this project!

[gilbsgilbs]

Looks like a beautiful and well-tested PR, thank you. Indeed, I completely missed #276 for some reasons, I'm very sorry @guiedugt.

@masnormen Would you mind rebasing this branch against his so that commit authorship is preserved, and squash your commits to make my review easier? Also, please add trailing newlines on files where they're missing (I thought prettier should have handled that, but maybe not). I'll approve just to let the CI run.

[gilbsgilbs]

Thanks! I'll try to do some maintenance chore, and draft a release tonight or tomorrow.