resources/page: Add :sectionslug and :sectionslugs permalink tokens

Add slugified section permalink tokens with fallback behavior and slice syntax support.

Fixes #13788

Author: DustinFischer

docs/content/en/_common/permalink-tokens.md

@@ -26,9 +26,15 @@ _comment: Do not remove front matter.
 `:section`
 : The content's section.
 
+`:sectionslug`
+: The content's section using slugified section name. The slugified section name is the `slug` as defined in front matter, else the `title` as defined in front matter, else the automatic title.
+
 `:sections`
 : The content's sections hierarchy. You can use a selection of the sections using _slice syntax_: `:sections[1:]` includes all but the first, `:sections[:last]` includes all but the last, `:sections[last]` includes only the last, `:sections[1:2]` includes section 2 and 3. Note that this slice access will not throw any out-of-bounds errors, so you don't have to be exact.
 
+`:sectionslugs`
+: The content's sections hierarchy using slugified section names. The slugified section name is the `slug` as defined in front matter, else the `title` as defined in front matter, else the automatic title. You can use a selection of the sections using _slice syntax_: `:sectionslugs[1:]` includes all but the first, `:sectionslugs[:last]` includes all but the last, `:sectionslugs[last]` includes only the last, `:sectionslugs[1:2]` includes section 2 and 3. Note that this slice access will not throw any out-of-bounds errors, so you don't have to be exact.
+
 `:title`
 : The `title` as defined in front matter, else the automatic title. Hugo generates titles automatically for section, taxonomy, and term pages that are not backed by a file.
 

resources/page/permalinks.go

@@ -62,6 +62,14 @@ func (p PermalinkExpander) callback(attr string) (pageToPermaAttribute, bool) {
 		}, true
 	}
 
+	if strings.HasPrefix(attr, "sectionslugs[") {
+		fn := p.toSliceFunc(strings.TrimPrefix(attr, "sectionslugs"))
+		sectionSlugsFunc := p.withSectionPagesFunc(p.pageToPermalinkSlugElseTitle, func(s ...string) string {
+			return path.Join(fn(s)...)
+		})
+		return sectionSlugsFunc, true
+	}
+
 	// Make sure this comes after all the other checks.
 	if referenceTime.Format(attr) != attr {
 		return p.pageToPermalinkDate, true
@@ -87,7 +95,9 @@ func NewPermalinkExpander(urlize func(uri string) string, patterns map[string]ma
 		"weekdayname":           p.pageToPermalinkDate,
 		"yearday":               p.pageToPermalinkDate,
 		"section":               p.pageToPermalinkSection,
+		"sectionslug":           p.pageToPermalinkSectionSlug,
 		"sections":              p.pageToPermalinkSections,
+		"sectionslugs":          p.pageToPermalinkSectionSlugs,
 		"title":                 p.pageToPermalinkTitle,
 		"slug":                  p.pageToPermalinkSlugElseTitle,
 		"slugorfilename":        p.pageToPermalinkSlugElseFilename,
@@ -305,10 +315,25 @@ func (l PermalinkExpander) pageToPermalinkSection(p Page, _ string) (string, err
 	return p.Section(), nil
 }
 
+// pageToPermalinkSectionSlug returns the URL-safe form of the first section's slug or title
+func (l PermalinkExpander) pageToPermalinkSectionSlug(p Page, attr string) (string, error) {
+	sectionPage := p.FirstSection()
+	if sectionPage == nil || sectionPage.IsHome() {
+		return "", nil
+	}
+	return l.pageToPermalinkSlugElseTitle(sectionPage, attr)
+}
+
 func (l PermalinkExpander) pageToPermalinkSections(p Page, _ string) (string, error) {
 	return p.CurrentSection().SectionsPath(), nil
 }
 
+// pageToPermalinkSectionSlugs returns a path built from all ancestor sections using their slugs or titles
+func (l PermalinkExpander) pageToPermalinkSectionSlugs(p Page, attr string) (string, error) {
+	sectionSlugsFunc := l.withSectionPagesFunc(l.pageToPermalinkSlugElseTitle, path.Join)
+	return sectionSlugsFunc(p, attr)
+}
+
 // pageToPermalinkContentBaseName returns the URL-safe form of the content base name.
 func (l PermalinkExpander) pageToPermalinkContentBaseName(p Page, _ string) (string, error) {
 	return l.urlize(p.PathInfo().Unnormalized().BaseNameNoIdentifier()), nil
@@ -333,6 +358,34 @@ func (l PermalinkExpander) translationBaseName(p Page) string {
 	return p.File().TranslationBaseName()
 }
 
+// withSectionPagesFunc returns a function that builds permalink attributes from section pages.
+// It applies the transformation function f to each ancestor section (Page), then joins the results with the join function.
+//
+// Current use is create section-based hierarchical paths using section slugs.
+func (l PermalinkExpander) withSectionPagesFunc(f func(Page, string) (string, error), join func(...string) string) func(p Page, s string) (string, error) {
+	return func(p Page, s string) (string, error) {
+		var entries []string
+		currentSection := p.CurrentSection()
+
+		// Build section hierarchy: ancestors (reversed to root-first) + current section
+		sections := currentSection.Ancestors().Reverse()
+		sections = append(sections, currentSection)
+
+		for _, section := range sections {
+			if section.IsHome() {
+				continue
+			}
+			entry, err := f(section, s)
+			if err != nil {
+				return "", err
+			}
+			entries = append(entries, entry)
+		}
+
+		return join(entries...), nil
+	}
+}
+
 var (
 	nilSliceFunc = func(s []string) []string {
 		return nil

resources/page/permalinks_integration_test.go

@@ -37,6 +37,9 @@ tag = "tags"
 [permalinks.page]
 withpageslug = '/pageslug/:slug/'
 withallbutlastsection = '/:sections[:last]/:slug/'
+withallbutlastsectionslug = '/:sectionslugs[:last]/:slug/'
+withsectionslug = '/sectionslug/:sectionslug/:slug/'
+withsectionslugs = '/sectionslugs/:sectionslugs/:slug/'
 [permalinks.section]
 withfilefilename = '/sectionwithfilefilename/:filename/'
 withfilefiletitle = '/sectionwithfilefiletitle/:title/'
@@ -64,6 +67,39 @@ slug: "withfileslugvalue"
 -- content/nofiletitle1/p1.md --
 -- content/nofiletitle2/asdf/p1.md --
 -- content/withallbutlastsection/subsection/p1.md --
+-- content/withallbutlastsectionslug/_index.md --
+---
+slug: "root-section-slug"
+---
+-- content/withallbutlastsectionslug/subsection/_index.md --
+---
+slug: "sub-section-slug"
+---
+-- content/withallbutlastsectionslug/subsection/p1.md --
+---
+slug: "page-slug"
+---
+-- content/withsectionslug/_index.md --
+---
+slug: "section-root-slug"
+---
+-- content/withsectionslug/subsection/_index.md --
+-- content/withsectionslug/subsection/p1.md --
+---
+slug: "page1-slug"
+---
+-- content/withsectionslugs/_index.md --
+---
+slug: "sections-root-slug"
+---
+-- content/withsectionslugs/level1/_index.md --
+---
+slug: "level1-slug"
+---
+-- content/withsectionslugs/level1/p1.md --
+---
+slug: "page1-slug"
+---
 -- content/tags/_index.md --
 ---
 slug: "tagsslug"
@@ -87,6 +123,8 @@ slug: "mytagslug"
 	// No .File.TranslationBaseName on zero object etc. warnings.
 	b.Assert(b.H.Log.LoggCount(logg.LevelWarn), qt.Equals, 0)
 	b.AssertFileContent("public/pageslug/p1slugvalue/index.html", "Single|page|/pageslug/p1slugvalue/|")
+	b.AssertFileContent("public/sectionslug/section-root-slug/page1-slug/index.html", "Single|page|/sectionslug/section-root-slug/page1-slug/|")
+	b.AssertFileContent("public/sectionslugs/sections-root-slug/level1-slug/page1-slug/index.html", "Single|page|/sectionslugs/sections-root-slug/level1-slug/page1-slug/|")
 	b.AssertFileContent("public/sectionwithfilefilename/index.html", "List|section|/sectionwithfilefilename/|")
 	b.AssertFileContent("public/sectionwithfileslug/withfileslugvalue/index.html", "List|section|/sectionwithfileslug/withfileslugvalue/|")
 	b.AssertFileContent("public/sectionnofilefilename/index.html", "List|section|/sectionnofilefilename/|")
@@ -99,7 +137,7 @@ slug: "mytagslug"
 
 	permalinksConf := b.H.Configs.Base.Permalinks
 	b.Assert(permalinksConf, qt.DeepEquals, map[string]map[string]string{
-		"page":     {"withallbutlastsection": "/:sections[:last]/:slug/", "withpageslug": "/pageslug/:slug/"},
+		"page":     {"withallbutlastsection": "/:sections[:last]/:slug/", "withallbutlastsectionslug": "/:sectionslugs[:last]/:slug/", "withpageslug": "/pageslug/:slug/", "withsectionslug": "/sectionslug/:sectionslug/:slug/", "withsectionslugs": "/sectionslugs/:sectionslugs/:slug/"},
 		"section":  {"nofilefilename": "/sectionnofilefilename/:filename/", "nofileslug": "/sectionnofileslug/:slug/", "nofiletitle1": "/sectionnofiletitle1/:title/", "nofiletitle2": "/sectionnofiletitle2/:sections[:last]/", "withfilefilename": "/sectionwithfilefilename/:filename/", "withfilefiletitle": "/sectionwithfilefiletitle/:title/", "withfileslug": "/sectionwithfileslug/:slug/"},
 		"taxonomy": {"tags": "/tagsslug/:slug/"},
 		"term":     {"tags": "/tagsslug/tag/:slug/"},
@@ -196,6 +234,55 @@ List.
 	b.AssertFileContent("public/libros/fiction/2023/book1/index.html", "Single.")
 }
 
+func TestPermalinksNestedSectionsWithSlugs(t *testing.T) {
+	t.Parallel()
+
+	files := `
+-- hugo.toml --
+[permalinks.page]
+books = '/libros/:sectionslugs[1:]/:slug'
+
+[permalinks.section]
+books = '/libros/:sectionslugs[1:]'
+-- content/books/_index.md --
+---
+title: Books
+---
+-- content/books/fiction/_index.md --
+---
+title: Fiction
+slug: fictionslug
+---
+-- content/books/fiction/2023/_index.md --
+---
+title: 2023
+---
+-- content/books/fiction/2023/book1/index.md --
+---
+title: Book One
+---
+-- layouts/_default/single.html --
+Single.
+-- layouts/_default/list.html --
+List.
+`
+
+	b := hugolib.NewIntegrationTestBuilder(
+		hugolib.IntegrationTestConfig{
+			T:           t,
+			TxtarString: files,
+			LogLevel:    logg.LevelWarn,
+		}).Build()
+
+	t.Log(b.LogString())
+	// No .File.TranslationBaseName on zero object etc. warnings.
+	b.Assert(b.H.Log.LoggCount(logg.LevelWarn), qt.Equals, 0)
+
+	b.AssertFileContent("public/libros/index.html", "List.")
+	b.AssertFileContent("public/libros/fictionslug/index.html", "List.")
+	b.AssertFileContent("public/libros/fictionslug/2023/book-one/index.html", "Single.")
+}
+
 func TestPermalinksUrlCascade(t *testing.T) {
 	t.Parallel()
 

resources/page/permalinks_test.go

@@ -62,6 +62,47 @@ var testdataPermalinks = []struct {
 		p.title = "mytitle"
 		p.file = source.NewContentFileInfoFrom("/", "_index.md")
 	}, "/test-page/"},
+	// slug, title.                                                         // Section slug
+	{"/:sectionslug/", true, func(p *testPage) {
+		p.currentSection = &testPage{slug: "my-slug"}
+	}, "/my-slug/"},
+	// slug, title.                                                         // Section slugs
+	{"/:sectionslugs/", true, func(p *testPage) {
+		// Set up current section with ancestors
+		currentSection := &testPage{
+			slug: "c-slug",
+			kind: "section",
+			ancestors: Pages{
+				&testPage{slug: "b-slug", kind: "section"},
+				&testPage{slug: "a-slug", kind: "section"},
+			},
+		}
+		p.currentSection = currentSection
+	}, "/a-slug/b-slug/c-slug/"},
+	// slice: slug, title.
+	{"/:sectionslugs[0]/:sectionslugs[last]/", true, func(p *testPage) {
+		currentSection := &testPage{
+			slug: "c-slug",
+			kind: "section",
+			ancestors: Pages{
+				&testPage{slug: "b-slug", kind: "section"},
+				&testPage{slug: "a-slug", kind: "section"},
+			},
+		}
+		p.currentSection = currentSection
+	}, "/a-slug/c-slug/"},
+	// slice: slug, title.
+	{"/:sectionslugs[last]/", true, func(p *testPage) {
+		currentSection := &testPage{
+			slug: "c-slug",
+			kind: "section",
+			ancestors: Pages{
+				&testPage{slug: "b-slug", kind: "section"},
+				&testPage{slug: "a-slug", kind: "section"},
+			},
+		}
+		p.currentSection = currentSection
+	}, "/c-slug/"},
 	// Failures
 	{"/blog/:fred", false, nil, ""},
 	{"/:year//:title", false, nil, ""},

resources/page/testhelpers_test.go

@@ -111,6 +111,7 @@ type testPage struct {
 
 	currentSection *testPage
 	sectionEntries []string
+	ancestors      Pages
 }
 
 func (p *testPage) Aliases() []string {
@@ -202,7 +203,12 @@ func (p *testPage) Filename() string {
 }
 
 func (p *testPage) FirstSection() Page {
-	panic("testpage: not implemented")
+	// Return the current section for regular pages
+	// For section pages, this would be the section itself
+	if p.currentSection != nil {
+		return p.currentSection
+	}
+	return p // If no current section, assume this page is the section
 }
 
 func (p *testPage) FuzzyWordCount(context.Context) int {
@@ -262,7 +268,7 @@ func (p *testPage) IsDraft() bool {
 }
 
 func (p *testPage) IsHome() bool {
-	panic("testpage: not implemented")
+	return p.kind == "home"
 }
 
 func (p *testPage) IsMenuCurrent(menuID string, inme *navigation.MenuEntry) bool {
@@ -278,15 +284,15 @@ func (p *testPage) IsPage() bool {
 }
 
 func (p *testPage) IsSection() bool {
-	panic("testpage: not implemented")
+	return p.kind == "section"
 }
 
 func (p *testPage) IsTranslated() bool {
 	panic("testpage: not implemented")
 }
 
 func (p *testPage) Ancestors() Pages {
-	panic("testpage: not implemented")
+	return p.ancestors
 }
 
 func (p *testPage) Keywords() []string {