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

1 files changed, 0 insertions, 153 deletions

diff --git a/hugolib/image_test.go b/hugolib/image_test.go
index ac18b9423..db1707c22 100644
--- a/hugolib/image_test.go
+++ b/hugolib/image_test.go
@@ -14,162 +14,9 @@
 package hugolib
 
 import (
-	"io"
-	"os"
-	"path/filepath"
-	"runtime"
-	"strings"
 	"testing"
-
-	"github.com/gohugoio/hugo/config"
-	"github.com/gohugoio/hugo/htesting"
-
-	qt "github.com/frankban/quicktest"
-	"github.com/gohugoio/hugo/hugofs"
 )
 
-// We have many tests for the different resize operations etc. in the resource package,
-// this is an integration test.
-func TestImageOps(t *testing.T) {
-	c := qt.New(t)
-	// Make this a real as possible.
-	workDir, clean, err := htesting.CreateTempDir(hugofs.Os, "image-resize")
-	c.Assert(err, qt.IsNil)
-	defer clean()
-
-	newBuilder := func(timeout any) *sitesBuilder {
-		v := config.NewWithTestDefaults()
-		v.Set("workingDir", workDir)
-		v.Set("baseURL", "https://example.org")
-		v.Set("timeout", timeout)
-
-		b := newTestSitesBuilder(t).WithWorkingDir(workDir)
-		b.Fs = hugofs.NewDefault(v)
-		b.WithViper(v)
-		b.WithContent("mybundle/index.md", `
----
-title: "My bundle"
----
-
-{{< imgproc >}}
-
-`)
-
-		b.WithTemplatesAdded(
-			"shortcodes/imgproc.html", `
-{{ $img := resources.Get "images/sunset.jpg" }}
-{{ $r := $img.Resize "129x239" }}
-IMG SHORTCODE: {{ $r.RelPermalink }}/{{ $r.Width }}
-`,
-			"index.html", `
-{{ $p := .Site.GetPage "mybundle" }}
-{{ $img1 := resources.Get "images/sunset.jpg" }}
-{{ $img2 := $p.Resources.GetMatch "sunset.jpg" }}
-{{ $img3 := resources.GetMatch "images/*.jpg" }}
-{{ $r := $img1.Resize "123x234" }}
-{{ $r2 := $r.Resize "12x23" }}
-{{ $b := $img2.Resize "345x678" }}
-{{ $b2 := $b.Resize "34x67" }}
-{{ $c := $img3.Resize "456x789" }}
-{{ $fingerprinted := $img1.Resize "350x" | fingerprint }}
-
-{{ $images := slice $r $r2 $b $b2 $c $fingerprinted }}
-
-{{ range $i, $r := $images }}
-{{ printf "Resized%d:" (add $i  1) }} {{ $r.Name }}|{{ $r.Width }}|{{ $r.Height }}|{{ $r.MediaType }}|{{ $r.RelPermalink }}|
-{{ end }}
-
-{{ $blurryGrayscale1 := $r | images.Filter images.Grayscale (images.GaussianBlur 8) }}
-BG1: {{ $blurryGrayscale1.RelPermalink }}/{{ $blurryGrayscale1.Width }}
-{{ $blurryGrayscale2 := $r.Filter images.Grayscale (images.GaussianBlur 8) }}
-BG2: {{ $blurryGrayscale2.RelPermalink }}/{{ $blurryGrayscale2.Width }}
-{{ $blurryGrayscale2_2 := $r.Filter images.Grayscale (images.GaussianBlur 8) }}
-BG2_2: {{ $blurryGrayscale2_2.RelPermalink }}/{{ $blurryGrayscale2_2.Width }}
-
-{{ $filters := slice images.Grayscale (images.GaussianBlur 9) }}
-{{ $blurryGrayscale3 := $r | images.Filter $filters }}
-BG3: {{ $blurryGrayscale3.RelPermalink }}/{{ $blurryGrayscale3.Width }}
-
-{{ $blurryGrayscale4 := $r.Filter $filters }}
-BG4: {{ $blurryGrayscale4.RelPermalink }}/{{ $blurryGrayscale4.Width }}
-
-{{ $p.Content }}
-
-`)
-
-		return b
-	}
-
-	imageDir := filepath.Join(workDir, "assets", "images")
-	bundleDir := filepath.Join(workDir, "content", "mybundle")
-
-	c.Assert(os.MkdirAll(imageDir, 0777), qt.IsNil)
-	c.Assert(os.MkdirAll(bundleDir, 0777), qt.IsNil)
-	src, err := os.Open("testdata/sunset.jpg")
-	c.Assert(err, qt.IsNil)
-	out, err := os.Create(filepath.Join(imageDir, "sunset.jpg"))
-	c.Assert(err, qt.IsNil)
-	_, err = io.Copy(out, src)
-	c.Assert(err, qt.IsNil)
-	out.Close()
-
-	src.Seek(0, 0)
-
-	out, err = os.Create(filepath.Join(bundleDir, "sunset.jpg"))
-	c.Assert(err, qt.IsNil)
-	_, err = io.Copy(out, src)
-	c.Assert(err, qt.IsNil)
-	out.Close()
-	src.Close()
-
-	// First build it with a very short timeout to trigger errors.
-	b := newBuilder("10ns")
-
-	imgExpect := `
-Resized1: images/sunset.jpg|123|234|image/jpeg|/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_123x234_resize_q75_box.jpg|
-Resized2: images/sunset.jpg|12|23|image/jpeg|/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_ada4bb1a57f77a63306e3bd67286248e.jpg|
-Resized3: sunset.jpg|345|678|image/jpeg|/mybundle/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_345x678_resize_q75_box.jpg|
-Resized4: sunset.jpg|34|67|image/jpeg|/mybundle/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_44d8c928664d7c5a67377c6ec58425ce.jpg|
-Resized5: images/sunset.jpg|456|789|image/jpeg|/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_456x789_resize_q75_box.jpg|
-Resized6: images/sunset.jpg|350|219|image/jpeg|/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_350x0_resize_q75_box.a86fe88d894e5db613f6aa8a80538fefc25b20fa24ba0d782c057adcef616f56.jpg|
-BG1: /images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_2ae8bb993431ec1aec40fe59927b46b4.jpg/123
-BG2: /images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_2ae8bb993431ec1aec40fe59927b46b4.jpg/123
-BG3: /images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_ed7740a90b82802261c2fbdb98bc8082.jpg/123
-BG4: /images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_ed7740a90b82802261c2fbdb98bc8082.jpg/123
-IMG SHORTCODE: /images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_129x239_resize_q75_box.jpg/129
-`
-
-	assertImages := func() {
-		b.Helper()
-		b.AssertFileContent("public/index.html", imgExpect)
-		b.AssertImage(350, 219, "public/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_350x0_resize_q75_box.a86fe88d894e5db613f6aa8a80538fefc25b20fa24ba0d782c057adcef616f56.jpg")
-		b.AssertImage(129, 239, "public/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_129x239_resize_q75_box.jpg")
-	}
-
-	err = b.BuildE(BuildCfg{})
-	if runtime.GOOS != "windows" && !strings.Contains(runtime.GOARCH, "arm") && !htesting.IsGitHubAction() {
-		// TODO(bep)
-		c.Assert(err, qt.Not(qt.IsNil))
-	}
-
-	b = newBuilder(29000)
-	b.Build(BuildCfg{})
-
-	assertImages()
-
-	// Truncate one image.
-	imgInCache := filepath.Join(workDir, "resources/_gen/images/sunset_hu59e56ffff1bc1d8d122b1403d34e039f_90587_ed7740a90b82802261c2fbdb98bc8082.jpg")
-	f, err := os.Create(imgInCache)
-	c.Assert(err, qt.IsNil)
-	f.Close()
-
-	// Build it again to make sure we read images from file cache.
-	b = newBuilder("30s")
-	b.Build(BuildCfg{})
-
-	assertImages()
-}
-
 func TestImageResizeMultilingual(t *testing.T) {
 	b := newTestSitesBuilder(t).WithConfigFile("toml", `
 baseURL="https://example.org"