* FEATURE: Optionally show topic excerpts in docs index
This commit adds a new docs_show_topic_excerpts site setting
which, when enabled and used in conjunction either with the
always_include_topic_excerpts site setting or the
serialize_topic_excerpts theme modifier.
For the theme modifier, this commit also fixes an issue
with the Docs::Query class. Since we were re-initializing
Guardian within the class (rather than using the guardian
passed down from the controller), we did not have the request
information needed to determine theme_id, which meant that
the theme modifier had no effect. We now pass down guardian
from the controller instead. In general guardian is almost
always better than a user object, since we can always just
call guardian.user.
Adds a simple system spec as well.
---
We now check both the serialize_topic_excerpts theme modifier
and the always_include_topic_excerpts site setting server-side
within Docs::Query, and use that on the client to determine
whether or not to show the excerpts for docs. This is because if
someone sets one of those values it's logical to think it will
apply everywhere there is a topic list.
Also include a system spec to test whether the theme modifier
works to show the excerpts.
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Co-authored-by: Martin Brennan <martin@discourse.org>