feat($plugin-last-updated): add "$page.lastUpdatedTimestamp"

[Kocal]

Summary

Some plugins depends of $page.lastUpdated to get the last updated date of a document, example https://github.com/lorisleiva/vuepress-plugin-seo or https://github.com/ekoeryanto/vuepress-plugin-sitemap.

However, due to the changes on the default transformer which adds support for localized date, passing a lang in the frontmatter header (ex: lang: fr) returns a string formatted like this 04/05/2021 à 23:29:04 which can't be parsed through new Date(), see lorisleiva/vuepress-plugin-seo#9 or https://github.com/ekoeryanto/vuepress-plugin-sitemap/blob/master/index.js#L24.

I don't think it's a nice idea to pass a custom transformer which just return the timestamp, because it means people will have to use theme inheritance just for re-formatting a localized date.

Instead, adding a new key lastUpdatedTimestamp which now contains the raw timestamp value without any transformation on it, in order to be easily used by other plugins.

WDYT?

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• Feature
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Other information:

[GregoireF]

Hi @Kocal,

I think your request can be closed.

Here is the working:
2345902#diff-9d5c9ea6cf449744a6a0f1d0d8dacf7a1aec22e97b1404b33eb8fa598ff3b9e2

Thanks for your implication ❤️

Cheers,

Gregoire FAVREAU

[Kocal]

Perfect! :)