Test Packs are not recompiled when changed

[richseviora]

Opening issue for visibility.

As mentioned in the discussion in PR #360, test packs are not recompiled when changed. If the packs-test directory (or your default) already exists, subsequent changes to app/javascript/pack will not cause the packs-test directory to be regenerated.

Webpacker::Manifest.lookup checks to see if the file is found (.find) but there's no freshness check.

[gauravtiwari]

@richseviora Please see this comment - #360 (comment)

[justin808]

@richseviora See #464. Also, I wrote the code for React on Rails that does this. We use the file mtimes.