#43, Update tree menu rendering to support multiple sections

layouts/partials/docs/menu-filetree.html

@@ -1,47 +1,59 @@
-<!-- Put configured sections list to .Scratch -->
-{{ template "book-get-root-section" . }} 
+{{ $bookSection := default "docs" .Site.Params.BookSection  }}
+{{ if eq $bookSection "*" }}
+  {{ .Scratch.Set "BookSections" .Site.Sections }}
+{{ else }}
+  {{ $bookSections := where .Site.Sections "Section" $bookSection }}
+  {{ .Scratch.Set "BookSections" $bookSections }}
+{{ end }}
 
-{{- range .Scratch.Get "BookSections" -}}
-  {{ template "book-section" (dict "Section" . "CurrentPage" $.Permalink) }}
-{{- end -}}
 
-{{ define "book-section" }} <!-- Single section of menu (recursive) -->
+{{ $sections := .Scratch.Get "BookSections" }}
+{{/* If there is only one section to render then render its children, else render all sections */}}
+{{ if eq (len $sections) 1 }} 
+  {{ with index $sections 0 }}
+    {{ template "book-section-children" (dict "Section" . "CurrentPage" $.Permalink) }}
+  {{ end }}
+{{ else }}
   <ul>
-    {{ range .Section.Sections }}
-    <li {{- if .Params.bookflatsection}} class="flat-section" {{ end }}>
-      {{- if .Content -}}
-        {{ template "book-page-link" (dict "Page" . "CurrentPage" $.CurrentPage) }}
-      {{- else -}}
-        {{- template "title" . -}}
-      {{- end -}}
+  {{ range $sections }}
+    {{ template "book-section" (dict "Section" . "CurrentPage" $.Permalink) }}
+  {{ end }}
+  </ul>
+{{ end }}
 
-      {{ template "book-section" (dict "Section" . "CurrentPage" $.CurrentPage) }}
-    </li>
+{{ define "book-section" }}
+{{ with .Section }}
+  <li {{ if .Params.bookFlatSection}} class="book-section-flat" {{ end }}>
+    {{ if .Content }}
+      {{ template "book-page-link" (dict "Page" . "CurrentPage" $.CurrentPage) }}
+    {{ else }}
+      <span>{{ template "title" . }}</span>
     {{ end }}
 
-    {{ range .Section.Pages }}
+    {{ template "book-section-children" (dict "Section" . "CurrentPage" $.CurrentPage) }}
+  </li>
+{{ end }}
+{{ end }}
+
+{{ define "book-section-children" }}
+{{ with .Section }}
+  <ul>
+    {{ range .Sections }}
+      {{ template "book-section" (dict "Section" . "CurrentPage" $.CurrentPage) }}
+    {{ end }}
+    {{ range .Pages }}
     <li>
       {{ template "book-page-link" (dict "Page" . "CurrentPage" $.CurrentPage) }}
     </li>
     {{ end }}
   </ul>
 {{ end }}
-
-{{ define "book-page-link" }}
-{{- with .Page -}}
-<a href="{{ .RelPermalink }}" {{- if eq $.CurrentPage .Permalink }} class="active"{{ end }}>
-  {{- template "title" . -}}
-</a>
-{{- end -}}
 {{ end }}
 
-{{ define "book-get-root-section" }}
-<!-- Complex logic to guess page title without .Title specified -->
-  {{ $bookSection := default "docs" .Site.Params.BookSection  }}
-  {{ if eq $bookSection "*" }}
-    {{ .Scratch.Set "BookSections" .Site.Sections }}
-  {{ else }}
-    {{ $bookSections := where .Site.Sections "Section" $bookSection }}
-    {{ .Scratch.Set "BookSections" $bookSections }}
-  {{ end }}
-{{ end }}
+{{ define "book-page-link" }}
+{{ with .Page }}
+  <a href="{{ .RelPermalink }}" {{ if eq $.CurrentPage .Permalink }} class="active"{{ end }}>
+    {{ template "title" . }}
+  </a>
+{{ end }}
+{{ end }}