This is preparation for #6041.
For historic reasons, the code for bulding the section tree and the taxonomies were very much separate.
This works, but makes it hard to extend, maintain, and possibly not so fast as it could be.
This simplification also introduces 3 slightly breaking changes, which I suspect most people will be pleased about. See referenced issues:
This commit also switches the radix tree dependency to a mutable implementation: github.com/armon/go-radix.
Fixes#6154Fixes#6153Fixes#6152
When using a html link checker with Hugo, this template consistently causes errors, as it renders `href=""` attributes when next/previous is disabled.
This change makes it so that the `href` attribute is not rendered at all if `HasNext` is false - which is better semantically, and makes link checking far easier.
The `safeHTMLAttr` function operates on a full attribute definition, not
just within the attribute value.
Docs: https://gohugo.io/functions/safehtmlattr/
For `opengraph.html`, run the whole `content` HTML attribute through
`safeHTMLAttr`. That will preserve `+` signs in formatted dates.
For `vimeo_simple.html`, `safeHTMLAttr` was in the context of an
attribute value, thus having no effect. In this case we could replace it
with `safeURL`, but since the code is coming from an API it is safer to
just let Go's template engine sanitize the value as it already does with
`provider_url`.
Fixes#5236 (no need to change Go upstream)
Related to #5246
* Rewind paginator for server mode
* Add some more related tests.
* Replace the clumsy scratch constructs in internal paginator template with variables
See #5825
The main motivation of this commit is to add a `page.Page` interface to replace the very file-oriented `hugolib.Page` struct.
This is all a preparation step for issue #5074, "pages from other data sources".
But this also fixes a set of annoying limitations, especially related to custom output formats, and shortcodes.
Most notable changes:
* The inner content of shortcodes using the `{{%` as the outer-most delimiter will now be sent to the content renderer, e.g. Blackfriday.
This means that any markdown will partake in the global ToC and footnote context etc.
* The Custom Output formats are now "fully virtualized". This removes many of the current limitations.
* The taxonomy list type now has a reference to the `Page` object.
This improves the taxonomy template `.Title` situation and make common template constructs much simpler.
See #5074Fixes#5763Fixes#5758Fixes#5090Fixes#5204Fixes#4695Fixes#5607Fixes#5707Fixes#5719Fixes#3113Fixes#5706Fixes#5767Fixes#5723Fixes#5769Fixes#5770Fixes#5771Fixes#5759Fixes#5776Fixes#5777Fixes#5778
The current full set of options for GA is now:
```toml
[privacy]
[privacy.googleAnalytics]
disable = false
respectDoNotTrack = true
anonymizeIP = true
useSessionStorage = true
```
Fixes#4775
