Simplify "active menu" logic for section menus

Fixes #8776

7 files changed, 151 insertions, 34 deletions

diff --git a/docs/content/en/functions/hasmenucurrent.md b/docs/content/en/functions/hasmenucurrent.md
index c7b8eb7a9..c53c91f94 100644
--- a/docs/content/en/functions/hasmenucurrent.md
+++ b/docs/content/en/functions/hasmenucurrent.md
@@ -24,4 +24,6 @@ aliases: []
 returns `true` if the PAGE is the same object as the `.Page` in one of the
 **children menu entries** under MENUENTRY in a given MENU.
 
+{{< new-in "0.86.0" >}} If MENUENTRY's `.Page` is a [section](/content-management/sections/) then, from Hugo `0.86.0`, this method also returns true for any descendant of that section..
+
 You can find its example use in [menu templates](/templates/menu-templates/).
diff --git a/docs/content/en/variables/menus.md b/docs/content/en/variables/menus.md
index d84837a43..9b8fe4d49 100644
--- a/docs/content/en/variables/menus.md
+++ b/docs/content/en/variables/menus.md
@@ -40,6 +40,9 @@ Reference to the [page object][page-object] associated with the menu entry. This
 will be non-nil if the menu entry is set via a page's front-matter and not via
 the site config.
 
+.PageRef {{< new-in "0.86.0" >}}
+: _string_ <br /> Can be set if defined in site config and the menu entry refers to a Page. [site.GetPage](/functions/getpage/) will be used to do the page lookup. If this is set, you don't need to set the `URL`.
+
 .Name
 : _string_ <br />
 Name of the menu entry. The `name` key, if set for the menu entry, sets
diff --git a/hugolib/menu_test.go b/hugolib/menu_test.go
index c43878090..a647c5bfa 100644
--- a/hugolib/menu_test.go
+++ b/hugolib/menu_test.go
@@ -33,7 +33,7 @@ menu:
 `
 )
 
-func TestSectionPagesMenu(t *testing.T) {
+func TestMenusSectionPagesMenu(t *testing.T) {
 	t.Parallel()
 
 	siteConfig := `
@@ -106,7 +106,7 @@ Menu Main:  {{ partial "menu.html" (dict "page" . "menu" "main") }}`,
 }
 
 // related issue #7594
-func TestMenuSort(t *testing.T) {
+func TestMenusSort(t *testing.T) {
 	b := newTestSitesBuilder(t).WithSimpleConfigFile()
 
 	b.WithTemplatesAdded("index.html", `
@@ -193,7 +193,7 @@ menu:
 	)
 }
 
-func TestMenuFrontMatter(t *testing.T) {
+func TestMenusFrontMatter(t *testing.T) {
 	b := newTestSitesBuilder(t).WithSimpleConfigFile()
 
 	b.WithTemplatesAdded("index.html", `
@@ -243,7 +243,7 @@ menu:
 }
 
 // https://github.com/gohugoio/hugo/issues/5849
-func TestMenuPageMultipleOutputFormats(t *testing.T) {
+func TestMenusPageMultipleOutputFormats(t *testing.T) {
 	config := `
 baseURL = "https://example.com"
 
@@ -301,7 +301,7 @@ menu: "main"
 }
 
 // https://github.com/gohugoio/hugo/issues/5989
-func TestMenuPageSortByDate(t *testing.T) {
+func TestMenusPageSortByDate(t *testing.T) {
 	b := newTestSitesBuilder(t).WithSimpleConfigFile()
 
 	b.WithContent("blog/a.md", `
@@ -399,3 +399,109 @@ key2: key2_config
 camelCase: camelCase_config
 `)
 }
+
+func TestMenusShadowMembers(t *testing.T) {
+	b := newTestSitesBuilder(t).WithConfigFile("toml", `
+[[menus.main]]
+identifier = "contact"
+pageRef = "contact"
+title = "Contact Us"
+url = "mailto:noreply@example.com"
+weight = 1
+[[menus.main]]
+pageRef = "/blog/post3"
+title = "My Post 3"
+url = "/blog/post3"
+	
+`)
+
+	commonTempl := `
+Main: {{ len .Site.Menus.main }}
+{{ range .Site.Menus.main }}
+{{ .Title }}|HasMenuCurrent: {{ $.HasMenuCurrent "main" . }}|Page: {{ .Page }}
+{{ .Title }}|IsMenuCurrent: {{ $.IsMenuCurrent "main" . }}|Page: {{ .Page }}
+{{ end }}
+`
+
+	b.WithTemplatesAdded("index.html", commonTempl)
+	b.WithTemplatesAdded("_default/single.html", commonTempl)
+
+	b.WithContent("_index.md", `
+---
+title: "Home"
+menu:
+  main:
+    weight: 10
+---
+`)
+
+	b.WithContent("blog/_index.md", `
+---
+title: "Blog"
+menu:
+  main:
+    weight: 20
+---
+`)
+
+	b.WithContent("blog/post1.md", `
+---
+title: "My Post 1: With  No Menu Defined"
+---
+`)
+
+	b.WithContent("blog/post2.md", `
+---
+title: "My Post 2: With Menu Defined"
+menu:
+  main:
+    weight: 30
+---
+`)
+
+	b.WithContent("blog/post3.md", `
+---
+title: "My Post 2: With  No Menu Defined"
+---
+`)
+
+	b.WithContent("contact.md", `
+---
+title: "Contact: With  No Menu Defined"
+---
+`)
+
+	b.Build(BuildCfg{})
+
+	b.AssertFileContent("public/index.html", `
+Main: 5
+Home|HasMenuCurrent: false|Page: Page(/_index.md)
+Blog|HasMenuCurrent: false|Page: Page(/blog/_index.md)
+My Post 2: With Menu Defined|HasMenuCurrent: false|Page: Page(/blog/post2.md)
+My Post 3|HasMenuCurrent: false|Page: Page(/blog/post3.md)
+Contact Us|HasMenuCurrent: false|Page: Page(/contact.md)
+`)
+
+	b.AssertFileContent("public/blog/post1/index.html", `
+Home|HasMenuCurrent: false|Page: Page(/_index.md)
+Blog|HasMenuCurrent: true|Page: Page(/blog/_index.md)
+`)
+
+	b.AssertFileContent("public/blog/post2/index.html", `
+Home|HasMenuCurrent: false|Page: Page(/_index.md)
+Blog|HasMenuCurrent: true|Page: Page(/blog/_index.md)
+Blog|IsMenuCurrent: false|Page: Page(/blog/_index.md)
+`)
+
+	b.AssertFileContent("public/blog/post3/index.html", `
+Home|HasMenuCurrent: false|Page: Page(/_index.md)
+Blog|HasMenuCurrent: true|Page: Page(/blog/_index.md)
+`)
+
+	b.AssertFileContent("public/contact/index.html", `
+Contact Us|HasMenuCurrent: false|Page: Page(/contact.md)
+Contact Us|IsMenuCurrent: true|Page: Page(/contact.md)
+Blog|HasMenuCurrent: false|Page: Page(/blog/_index.md)
+Blog|IsMenuCurrent: false|Page: Page(/blog/_index.md)
+`)
+}
diff --git a/hugolib/page__menus.go b/hugolib/page__menus.go
index e64ffa2c9..49d392c2f 100644
--- a/hugolib/page__menus.go
+++ b/hugolib/page__menus.go
@@ -56,7 +56,6 @@ func (p *pageMenus) menus() navigation.PageMenus {
 func (p *pageMenus) init() {
 	p.pmInit.Do(func() {
 		p.q = navigation.NewMenuQueryProvider(
-			p.p.s.Info.sectionPagesMenu,
 			p,
 			p.p.s,
 			p.p,
diff --git a/hugolib/site.go b/hugolib/site.go
index fe7305b91..e687710bf 100644
--- a/hugolib/site.go
+++ b/hugolib/site.go
@@ -1452,6 +1452,10 @@ func (s *Site) assembleMenus() {
 	menuConfig := s.getMenusFromConfig()
 	for name, menu := range menuConfig {
 		for _, me := range menu {
+			if types.IsNil(me.Page) && me.PageRef != "" {
+				// Try to resolve the page.
+				me.Page, _ = s.getPageNew(nil, me.PageRef)
+			}
 			flat[twoD{name, me.KeyName()}] = me
 		}
 	}
diff --git a/navigation/menu.go b/navigation/menu.go
index 3ef06f6a9..7c6a1ccc7 100644
--- a/navigation/menu.go
+++ b/navigation/menu.go
@@ -32,6 +32,7 @@ var smc = newMenuCache()
 type MenuEntry struct {
 	ConfiguredURL string // The URL value from front matter / config.
 	Page          Page
+	PageRef       string // The path to the page, only relevant for site config.
 	Name          string
 	Menu          string
 	Identifier    string
@@ -63,6 +64,8 @@ type Page interface {
 	Section() string
 	Weight() int
 	IsPage() bool
+	IsSection() bool
+	IsAncestor(other interface{}) (bool, error)
 	Params() maps.Params
 }
 
@@ -106,16 +109,28 @@ func (m *MenuEntry) IsEqual(inme *MenuEntry) bool {
 // IsSameResource returns whether the two menu entries points to the same
 // resource (URL).
 func (m *MenuEntry) IsSameResource(inme *MenuEntry) bool {
+	if m.isSamePage(inme.Page) {
+		return m.Page == inme.Page
+	}
 	murl, inmeurl := m.URL(), inme.URL()
 	return murl != "" && inmeurl != "" && murl == inmeurl
 }
 
+func (m *MenuEntry) isSamePage(p Page) bool {
+	if !types.IsNil(m.Page) && !types.IsNil(p) {
+		return m.Page == p
+	}
+	return false
+}
+
 func (m *MenuEntry) MarshallMap(ime map[string]interface{}) {
 	for k, v := range ime {
 		loki := strings.ToLower(k)
 		switch loki {
 		case "url":
 			m.ConfiguredURL = cast.ToString(v)
+		case "pageref":
+			m.PageRef = cast.ToString(v)
 		case "weight":
 			m.Weight = cast.ToInt(v)
 		case "name":
diff --git a/navigation/pagemenus.go b/navigation/pagemenus.go
index 1dfa71255..f783e30cf 100644
--- a/navigation/pagemenus.go
+++ b/navigation/pagemenus.go
@@ -15,6 +15,7 @@ package navigation
 
 import (
 	"github.com/gohugoio/hugo/common/maps"
+	"github.com/gohugoio/hugo/common/types"
 
 	"github.com/pkg/errors"
 	"github.com/spf13/cast"
@@ -97,31 +98,25 @@ func PageMenusFromPage(p Page) (PageMenus, error) {
 }
 
 func NewMenuQueryProvider(
-	setionPagesMenu string,
 	pagem PageMenusGetter,
 	sitem MenusGetter,
 	p Page) MenuQueryProvider {
 	return &pageMenus{
-		p:               p,
-		pagem:           pagem,
-		sitem:           sitem,
-		setionPagesMenu: setionPagesMenu,
+		p:     p,
+		pagem: pagem,
+		sitem: sitem,
 	}
 }
 
 type pageMenus struct {
-	pagem           PageMenusGetter
-	sitem           MenusGetter
-	setionPagesMenu string
-	p               Page
+	pagem PageMenusGetter
+	sitem MenusGetter
+	p     Page
 }
 
 func (pm *pageMenus) HasMenuCurrent(menuID string, me *MenuEntry) bool {
-	// page is labeled as "shadow-member" of the menu with the same identifier as the section
-	if pm.setionPagesMenu != "" {
-		section := pm.p.Section()
-
-		if section != "" && pm.setionPagesMenu == menuID && section == me.Identifier {
+	if !types.IsNil(me.Page) && me.Page.IsSection() {
+		if ok, _ := me.Page.IsAncestor(pm.p); ok {
 			return true
 		}
 	}
@@ -143,18 +138,15 @@ func (pm *pageMenus) HasMenuCurrent(menuID string, me *MenuEntry) bool {
 		}
 	}
 
-	if pm.p == nil || pm.p.IsPage() {
+	if pm.p == nil {
 		return false
 	}
 
-	// The following logic is kept from back when Hugo had both Page and Node types.
-	// TODO(bep) consolidate / clean
-	nme := MenuEntry{Page: pm.p, Name: pm.p.LinkTitle()}
-
 	for _, child := range me.Children {
-		if nme.IsSameResource(child) {
+		if child.isSamePage(pm.p) {
 			return true
 		}
+
 		if pm.HasMenuCurrent(menuID, child) {
 			return true
 		}
@@ -172,20 +164,16 @@ func (pm *pageMenus) IsMenuCurrent(menuID string, inme *MenuEntry) bool {
 		}
 	}
 
-	if pm.p == nil || pm.p.IsPage() {
+	if pm.p == nil {
 		return false
 	}
 
-	// The following logic is kept from back when Hugo had both Page and Node types.
-	// TODO(bep) consolidate / clean
-	me := MenuEntry{Page: pm.p, Name: pm.p.LinkTitle()}
-
-	if !me.IsSameResource(inme) {
+	if !inme.isSamePage(pm.p) {
 		return false
 	}
 
-	// this resource may be included in several menus
-	// search for it to make sure that it is in the menu with the given menuId
+	// This resource may be included in several menus.
+	// Search for it to make sure that it is in the menu with the given menuId.
 	if menu, ok := pm.sitem.Menus()[menuID]; ok {
 		for _, menuEntry := range menu {
 			if menuEntry.IsSameResource(inme) {