Allow excerpts to be generated for Page objects

[ashmaroli]

• This is a 🙋 feature or enhancement.

Summary

Allow excerpts to be generated for Jekyll::Page objects.

Currently just a bare-bones feature, {{ page.excerpt }} for a Jekyll::Page will yield just the rendered output string of the Page's excerpt-source.

Context

Resolves #6778

[mattr-]

If this is ready to go, can we move it out of draft and into ready for review?

[ashmaroli]

Unfortunately since this breaks existing builds, it is not ready to move out of the draft status.

[ashmaroli]

@jekyllbot: merge +minor

[seth-reeser]

Hello, this had an unintended consequence, I would recommend stripping html, stripping newlines, and even maybe truncating. I was using page.excerpt as a meta description entry:

<meta name="description" content="{% if page.excerpt %}{{ page.excerpt | strip_html | strip_newlines | truncate: 160 }}{% else %}{{ site.description }}{% endif %}">

In an example of an excerpt not being defined for a page, this would have evaluated to the site.description, but now I'm getting markup generated for me that breaks because of HTML being included.

[ashmaroli]

@seth-reeser Please open a new issue ticket and include the expected and actual results in the ticket for a discussion.