SI-9006 Scaladoc: explicit companion and package links

The existing navigation mechanisms have proved hard to discover for newcomers
to Scaladoc.

This commit adds textual links in the navigation bar to the docs of the
companion (if defined) and to those of the enclosing package.

3 files changed, 35 insertions, 1 deletions

diff --git a/src/scaladoc/scala/tools/nsc/doc/html/HtmlPage.scala b/src/scaladoc/scala/tools/nsc/doc/html/HtmlPage.scala
index 295bae5bef..3738e79ffe 100644
--- a/src/scaladoc/scala/tools/nsc/doc/html/HtmlPage.scala
+++ b/src/scaladoc/scala/tools/nsc/doc/html/HtmlPage.scala
@@ -228,6 +228,26 @@ abstract class HtmlPage extends Page { thisPage =>
       </a>
     </span>
 
+  def companionAndPackage(tpl: DocTemplateEntity): Elem =
+    <span class="morelinks">{
+      tpl.companion match {
+        case Some(companionTpl) =>
+          val objClassTrait =
+            if (companionTpl.isObject) s"object ${tpl.name}"
+            else if (companionTpl.isTrait) s"trait ${companionTpl.name}"
+            else s"class ${companionTpl.name}"
+          <div>
+            Related Docs:
+            <a href={relativeLinkTo(tpl.companion.get)} title="See companion">{objClassTrait}</a>
+            | {templateToHtml(tpl.inTemplate, s"package ${tpl.inTemplate.name}")}
+          </div>
+        case None =>
+          <div>Related Doc:
+            {templateToHtml(tpl.inTemplate, s"package ${tpl.inTemplate.name}")}
+          </div>
+      }
+    }</span>
+
   def memberToUrl(template: Entity, isSelf: Boolean = true): String = {
     val (signature: Option[String], containingTemplate: TemplateEntity) = template match {
       case dte: DocTemplateEntity if (!isSelf) => (Some(dte.signature), dte.inTemplate)
diff --git a/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala b/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala
index f3df2b0bb4..eda52c5fbf 100644
--- a/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala
+++ b/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala
@@ -110,7 +110,9 @@ class Template(universe: doc.Universe, generator: DiagramGenerator, tpl: DocTemp
               <img src={ relativeLinkTo(List(docEntityKindToBigImage(tpl), "lib")) }/>
         }}
         { owner }
-        <h1>{ displayName }</h1> { permalink(tpl) }
+        <h1>{ displayName }</h1>{
+          if (tpl.isPackage) NodeSeq.Empty else <h3>{companionAndPackage(tpl)}</h3>
+        }{ permalink(tpl) }
       </div>
 
       { signature(tpl, isSelf = true) }
diff --git a/src/scaladoc/scala/tools/nsc/doc/html/resource/lib/template.css b/src/scaladoc/scala/tools/nsc/doc/html/resource/lib/template.css
index 35f66cd5df..e129e6cf6a 100644
--- a/src/scaladoc/scala/tools/nsc/doc/html/resource/lib/template.css
+++ b/src/scaladoc/scala/tools/nsc/doc/html/resource/lib/template.css
@@ -397,6 +397,18 @@ div.members > ol > li:last-child {
   margin-bottom: 5px;
 }
 
+#definition .morelinks {
+  text-align: right;
+  position: absolute;
+  top: 40px;
+  right: 10px;
+  width: 450px;
+}
+
+#definition .morelinks a {
+  color: #EBEBEB;
+}
+
 #template .members li .permalink {
   position: absolute;
   top: 5px;