✨ Expose used chrome versions

[olebedev]

Background

The @percy/core package manages chromium version on its own when no executables provided, so there is no versions mismatch possible in this scenario. However, when the PERCY_BROWSER_EXECUTABLE env var is set to point to a chromium executable it becomes difficult to manage the chromium version and keep it aligned with the ones that the library is supposed to work with. Especially, when the dependency definition in package.json file is set like:

{
  ...
  "peerDependencies": {
    "@percy/core": "*",
  },
  ...
}

In this PR

Expose chromium versions to be able to assert that the local one fits the requirement. For example:

const { chromium } = require('@percy/core/dist/install');
assert.equal(
  '812847',
  chromium.revisions.linux,
  'The local chromium version for @percy/core don\'t match the expected one!',
);

By exposing the chromium version, we can provide a guarantee that the versions are matching along with the ability to upgrade the library independently while the local and required versions are the same.

cc @joscha

[wwilsman]

Hey @olebedev! Thanks for the PR!

Only small suggestion would be to set this property as installChromium.revisions since these revisions only pertain to this particular function. Then you can remove the additional export and access revisions as install.chromium.revisions.

[olebedev]

Hi @wwilsman, done in d6e879e, please have a look!

[wwilsman]

Thanks for the contribution!

Our CI events weren't set up properly for forks at the time you forked, so I'll just go ahead and merge this anyway with pending checks since I don't foresee any issues from this change. 😄

[joscha]

Thanks @wwilsman! Can you ping here when this goes into a new version, please?

[Robdel12]

Boom went out in 1.0.0-beta.47 (https://github.com/percy/cli/releases/tag/v1.0.0-beta.47) @joscha / @olebedev :D thanks for the PR!