Hide empty/unspecified projectUrl and projectLogo

The condition `{% if site.projectUrl %}` only filters out `null` values, 
not empty ones.

Author: TheElectronWill

doc-tool/src/dotty/tools/dottydoc/DocDriver.scala

@@ -41,8 +41,8 @@ class DocDriver extends Driver {
     val siteRoot = new java.io.File(ctx.settings.siteRoot.value)
     val projectName = ctx.settings.projectName.value
     val projectVersion = ctx.settings.projectVersion.value
-    val projectUrl = ctx.settings.projectUrl.value
-    val projectLogo = ctx.settings.projectLogo.value
+    val projectUrl = Option(ctx.settings.projectUrl.value).filter(_.nonEmpty)
+    val projectLogo = Option(ctx.settings.projectLogo.value).filter(_.nonEmpty)
 
     if (projectName.isEmpty)
       ctx.error(s"Site project name not set. Use `-project <title>` to set the project name")

doc-tool/src/dotty/tools/dottydoc/staticsite/DefaultParams.scala

@@ -39,8 +39,8 @@ case class DefaultParams(
         "posts" -> site.posts.map(_.toMap),
         "project" -> site.projectTitle,
         "version" -> site.projectVersion,
-        "projectUrl" -> site.projectUrl,
-        "logo" -> site.projectLogo,
+        "projectUrl" -> site.projectUrl.orNull,
+        "logo" -> site.projectLogo.orNull,
         "root" -> site.root
       ).asJava,
 
@@ -76,8 +76,8 @@ case class SiteInfo(
   baseurl: String,
   projectTitle: String,
   projectVersion: String,
-  projectUrl: String,
-  projectLogo: String,
+  projectUrl: Option[String],
+  projectLogo: Option[String],
   posts: Array[BlogPost],
   root: String
 )

doc-tool/src/dotty/tools/dottydoc/staticsite/Site.scala

@@ -33,8 +33,8 @@ case class Site(
   root: JFile,
   projectTitle: String,
   projectVersion: String,
-  projectUrl: String,
-  projectLogo: String,
+  projectUrl: Option[String],
+  projectLogo: Option[String],
   documentation: Map[String, Package]
 ) extends ResourceFinder {
   /** Documentation serialized to java maps */

doc-tool/test/dotty/tools/dottydoc/staticsite/SourceFileOps.scala

@@ -13,7 +13,7 @@ trait SourceFileOps {
   import scala.collection.JavaConverters._
   val site = new Site(
     new java.io.File("doc-tool/resources/"),
-    "test-site", "v0.1", "http://github.com/lampepfl/dotty", Map.empty
+    "test-site", "v0.1", Some("http://github.com/lampepfl/dotty"), None, Map.empty
   )
 
   def stringToSource(path: String, sourceCode: String): SourceFile = {