hugo/common/collections/slice.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

97 lines
2.3 KiB
Go

// Copyright 2018 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 collections
import (
"reflect"
"sort"
)
// Slicer defines a very generic way to create a typed slice. This is used
// in collections.Slice template func to get types such as Pages, PageGroups etc.
// instead of the less useful []interface{}.
type Slicer interface {
Slice(items any) (any, error)
}
// Slice returns a slice of all passed arguments.
func Slice(args ...any) any {
if len(args) == 0 {
return args
}
first := args[0]
firstType := reflect.TypeOf(first)
if firstType == nil {
return args
}
if g, ok := first.(Slicer); ok {
v, err := g.Slice(args)
if err == nil {
return v
}
// If Slice fails, the items are not of the same type and
// []interface{} is the best we can do.
return args
}
if len(args) > 1 {
// This can be a mix of types.
for i := 1; i < len(args); i++ {
if firstType != reflect.TypeOf(args[i]) {
// []interface{} is the best we can do
return args
}
}
}
slice := reflect.MakeSlice(reflect.SliceOf(firstType), len(args), len(args))
for i, arg := range args {
slice.Index(i).Set(reflect.ValueOf(arg))
}
return slice.Interface()
}
// StringSliceToInterfaceSlice converts ss to []interface{}.
func StringSliceToInterfaceSlice(ss []string) []any {
result := make([]any, len(ss))
for i, s := range ss {
result[i] = s
}
return result
}
type SortedStringSlice []string
// Contains returns true if s is in ss.
func (ss SortedStringSlice) Contains(s string) bool {
i := sort.SearchStrings(ss, s)
return i < len(ss) && ss[i] == s
}
// Count returns the number of times s is in ss.
func (ss SortedStringSlice) Count(s string) int {
var count int
i := sort.SearchStrings(ss, s)
for i < len(ss) && ss[i] == s {
count++
i++
}
return count
}