Add Page.Contents with scope support

Fixes gohugoio#8680
Fixes gohugoio#12761

common/hugo/hugo.go

@@ -14,6 +14,7 @@
 package hugo
 
 import (
+	"context"
 	"fmt"
 	"html/template"
 	"os"
@@ -29,6 +30,7 @@ import (
 	"github.com/mitchellh/mapstructure"
 
 	"github.com/bep/godartsass/v2"
+	"github.com/gohugoio/hugo/common/hcontext"
 	"github.com/gohugoio/hugo/common/hexec"
 	"github.com/gohugoio/hugo/common/loggers"
 	"github.com/gohugoio/hugo/hugofs/files"
@@ -69,6 +71,9 @@ type HugoInfo struct {
 
 	conf ConfigProvider
 	deps []*Dependency
+
+	// Context gives access to some of the context scoped variables.
+	Context Context
 }
 
 // Version returns the current version as a comparable version string.
@@ -127,6 +132,21 @@ func (i HugoInfo) IsMultilingual() bool {
 	return i.conf.IsMultilingual()
 }
 
+type contextKey string
+
+var markupScope = hcontext.NewContextDispatcher[string](contextKey("markupScope"))
+
+type Context struct{}
+
+func (c Context) MarkupScope(ctx context.Context) string {
+	return markupScope.Get(ctx)
+}
+
+// For internal use only.
+func SetMarkupScope(ctx context.Context, s string) context.Context {
+	return markupScope.Set(ctx, s)
+}
+
 // ConfigProvider represents the config options that are relevant for HugoInfo.
 type ConfigProvider interface {
 	Environment() string

common/hugo/hugo_test.go

@@ -14,6 +14,7 @@
 package hugo
 
 import (
+	"context"
 	"fmt"
 	"testing"
 
@@ -64,6 +65,19 @@ func TestDeprecationLogLevelFromVersion(t *testing.T) {
 	c.Assert(deprecationLogLevelFromVersion(ver.String()), qt.Equals, logg.LevelError)
 }
 
+func TestMarkupScope(t *testing.T) {
+	c := qt.New(t)
+
+	conf := testConfig{environment: "production", workingDir: "/mywork", running: false}
+	info := NewInfo(conf, nil)
+
+	ctx := context.Background()
+
+	ctx = SetMarkupScope(ctx, "foo")
+
+	c.Assert(info.Context.MarkupScope(ctx), qt.Equals, "foo")
+}
+
 type testConfig struct {
 	environment  string
 	running      bool

hugolib/page.go

@@ -61,6 +61,7 @@ var (
 	pageTypesProvider = resource.NewResourceTypesProvider(media.Builtin.OctetType, pageResourceType)
 	nopPageOutput     = &pageOutput{
 		pagePerOutputProviders: nopPagePerOutput,
+		ContentsProvider:       page.NopPage,
 		ContentProvider:        page.NopPage,
 	}
 )
@@ -213,11 +214,8 @@ func (p *pageHeadingsFiltered) page() page.Page {
 
 // For internal use by the related content feature.
 func (p *pageState) ApplyFilterToHeadings(ctx context.Context, fn func(*tableofcontents.Heading) bool) related.Document {
-	r, err := p.m.content.contentToC(ctx, p.pageOutput.pco)
-	if err != nil {
-		panic(err)
-	}
-	headings := r.tableOfContents.Headings.FilterBy(fn)
+	fragments := p.pageOutput.pco.c().Fragments(ctx)
+	headings := fragments.Headings.FilterBy(fn)
 	return &pageHeadingsFiltered{
 		pageState: p,
 		headings:  headings,