Note: At the moment current it will fail when having

const cacheAge = [["no-cache"]].filter(v => v[0] === 'max-age').map(v => v[1])[0] // this is undefined
cacheAge.length // This is an error

Could this be added as test 👍

I am trying to see how to test it to be honest :) any help?

@alan-agius4 I am not familiar with the service worker code at all, sorry. At first glance, looks like we can pull out quite a bit to a separate pure function to easily test:

export function parseCacheControlIntoMaxAge(cacheControl: string) {
      const cacheDirectives =
          cacheControl
              // Directives are comma-separated within the Cache-Control header value.
              .split(',')
              // Make sure each directive doesn't have extraneous whitespace.
              .map(v => v.trim())
              // Some directives have values (like maxage and s-maxage)
              .map(v => v.split('='));

      // Find the max-age directive, if one exists.
      const maxAge = cacheDirectives.find(v => v[0].toLowerCase() === 'max-age');
      return maxAge ? maxAge[1] : undefined;
}

Let's see what @gkalpak thinks 👍

I managed to test it. Thanks anyways.

Also for me personally, I don't like to export a function just to be able to unit test it.

I'm okay with exporting it just to test it. Exporting it from a private module within the package is different than exporting it as public API.

Yep you are absolutely right.

There is a maxAge variable declared few lines below. Consider giving them different names to avoid confusion.

@gkalpak, I updated it.

maxAgeDirective[1] ?