hugo/compare/compare.go
Bjørn Erik Pedersen 90da7664bf Add page fragments support to Related
The main topic of this commit is that you can now index fragments (content heading identifiers) when calling `.Related`.

You can do this by:

* Configure one or more indices with type `fragments`
* The name of those index configurations maps to an (optional) front matter slice with fragment references. This allows you to link
page<->fragment and page<->page.
* This also will index all the fragments (heading identifiers) of the pages.

It's also possible to use type `fragments` indices in shortcode, e.g.:

```
{{ $related := site.RegularPages.Related .Page }}
```

But, and this is important, you need to include the shortcode using the `{{<` delimiter. Not doing so will create infinite loops and timeouts.

This commit also:

* Adds two new methods to Page: Fragments (can also be used to build ToC) and HeadingsFiltered (this is only used in Related Content with
index type `fragments` and `enableFilter` set to true.
* Consolidates all `.Related*` methods into one, which takes either a `Page` or an options map as its only argument.
* Add `context.Context` to all of the content related Page API. Turns out it wasn't strictly needed for this particular feature, but it will
soon become usefil, e.g. in #9339.

Closes #10711
Updates #9339
Updates #10725
2023-02-21 17:56:41 +01:00

54 lines
1.7 KiB
Go

// Copyright 2019 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package compare
// Eqer can be used to determine if this value is equal to the other.
// The semantics of equals is that the two value are interchangeable
// in the Hugo templates.
type Eqer interface {
// Eq returns whether this value is equal to the other.
// This is for internal use.
Eq(other any) bool
}
// ProbablyEqer is an equal check that may return false positives, but never
// a false negative.
type ProbablyEqer interface {
// For internal use.
ProbablyEq(other any) bool
}
// Comparer can be used to compare two values.
// This will be used when using the le, ge etc. operators in the templates.
// Compare returns -1 if the given version is less than, 0 if equal and 1 if greater than
// the running version.
type Comparer interface {
Compare(other any) int
}
// Eq returns whether v1 is equal to v2.
// It will use the Eqer interface if implemented, which
// defines equals when two value are interchangeable
// in the Hugo templates.
func Eq(v1, v2 any) bool {
if v1 == nil || v2 == nil {
return v1 == v2
}
if eqer, ok := v1.(Eqer); ok {
return eqer.Eq(v2)
}
return v1 == v2
}