Issue 14868. Show both errors/warnings and Dart doc.

editor/tools/plugins/com.google.dart.tools.ui/src/com/google/dart/tools/ui/internal/text/editor/DartTextHover.java

 /*
  * Copyright (c) 2012, the Dart project authors.
  * 
  * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
  * in compliance with the License. You may obtain a copy of the License at
  * 
  * http://www.eclipse.org/legal/epl-v10.html
  * 
  * Unless required by applicable law or agreed to in writing, software distributed under the License
  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
@@ skipping 64 matching lines @@
 
   /**
    * Remove a hover contributor
    * 
    * @param hoverContributor
    */
   public static void removeContributer(ITextHover hoverContributor) {
     hoverContributors.remove(hoverContributor);
   }
 
+  private static StringBuilder append(StringBuilder buffer, String s) {
+    if (buffer.length() != 0) {
+      buffer.append("<br><br>");
+    }
+    if (s != null) {
+      buffer.append(s);
+    }
+    return buffer;
+  }
+
   private CompilationUnitEditor editor;
 
   private DartSourceViewerConfiguration sourceViewerConfiguration;
 
   private ITextHover lastReturnedHover;
 
   public DartTextHover(ITextEditor editor, ISourceViewer sourceViewer,
       DartSourceViewerConfiguration sourceViewerConfiguration) {
     super(sourceViewer);
 
@@ skipping 37 matching lines @@
     // Check for a dartdoc contribution.
     return getDartDocHover(region);
   }
 
   @Override
   public Object getHoverInfo2(ITextViewer textViewer, IRegion region) {
     // Overridden from ITextHoverExtension2. We try and return the richest help available; this
     // means trying to call getHoverInfo2() on any contributors, and falling back on getHoverInfo().
     lastReturnedHover = null;
 
-    // Return any annotation info - i.e. errors and warnings.
+    StringBuilder buffer = new StringBuilder();
+
+    // Append any annotation info - i.e. errors and warnings.
     String annotationHover = super.getHoverInfo(textViewer, region);
-
-    if (annotationHover != null) {
-      return escapeHtmlEntities(annotationHover);
-    }
+    append(buffer, escapeHtmlEntities(annotationHover));
 
     // Check through the contributed hover providers.
     for (ITextHover hoverContributer : hoverContributors) {
       if (hoverContributer instanceof ITextHoverExtension2) {
         Object hoverInfo = ((ITextHoverExtension2) hoverContributer).getHoverInfo2(
             textViewer,
             region);
 
         if (hoverInfo != null) {
           lastReturnedHover = hoverContributer;
-
           return hoverInfo;
         }
       } else {
         String hoverText = hoverContributer.getHoverInfo(textViewer, region);
 
         if (hoverText != null) {
           lastReturnedHover = hoverContributer;
-
           return hoverText;
         }
       }
     }
 
     // Check for a dartdoc contribution.
-    return getDartDocHover(region);
+    String dartDocHover = getDartDocHover(region);
+    return append(buffer, dartDocHover).toString();
   }
 
   @Override
   protected boolean isIncluded(Annotation annotation) {
     return sourceViewerConfiguration.isShownInText(annotation);
   }
 
   private String escapeHtmlEntities(String str) {
     str = str.replace("&", "&amp;").replace("<", "&lt;").replace(">", "&gt;");
 
     return str;
   }
 
   /**
    * Return the associated DartDoc hover, if any.
    */
   private String getDartDocHover(IRegion region) {
     if (editor != null) {
       Element element = NewSelectionConverter.getElementAtOffset(editor, region.getOffset());
       return getElementDocumentationHtml(element);
     }
 
     return null;
   }
 
 }