While editing description, inline help should show the syntax guide based on...

While editing description, inline help should show the syntax guide based on the current markup formatter.

changelog.html

@@ -74,6 +74,8 @@ Upcoming changes</a>
     Fixed a XSS vulnerability in the project relationship page.
   <li class=rfe>
     Added a new extension point to expose unprotected root action.
+  <li class=rfe>
+    While editing description, inline help should show the syntax guide based on the current markup formatter.
 </ul>
 </div><!--=TRUNK-END=-->
 

core/src/main/java/hudson/markup/MarkupFormatter.java

@@ -69,6 +69,20 @@ public abstract class MarkupFormatter extends AbstractDescribableImpl<MarkupForm
         return w.toString();
     }
 
+    /**
+     * Gets the URL of the help file. This help will shown next to the text area of the description,
+     * and is ideal of describing what the allowed syntax is.
+     *
+     * By default, we look for colocated help-syntax.html.
+     *
+     * @since 1.398
+     * @return null
+     *      If there's no help file.
+     */
+    public String getHelpUrl() {
+        return getDescriptor().getHelpFile("syntax");
+    }
+
     @Override
     public MarkupFormatterDescriptor getDescriptor() {
         return (MarkupFormatterDescriptor)super.getDescriptor();

core/src/main/resources/hudson/model/AbstractModelObject/descriptionForm.jelly

@@ -31,7 +31,11 @@ THE SOFTWARE.
   </j:if>
   <l:ajax>
     <form action="submitDescription" method="post">
-      <f:textarea name="description" value="${it.description}" />
+      <table>
+        <f:entry help="${app.markupFormatter.helpUrl}">
+          <f:textarea name="description" value="${it.description}" />
+        </f:entry>
+      </table>
       <div align="right">
         <f:submit value="${%Submit}" />
       </div>

core/src/main/resources/hudson/model/AbstractModelObject/editDescription.jelly

@@ -30,7 +30,11 @@ THE SOFTWARE.
     <st:include page="sidepanel.jelly" />
     <l:main-panel>
       <form action="submitDescription" method="post">
-        <f:textarea name="description" value="${it.description}" />
+        <table>
+          <f:entry help="${app.markupFormatter.helpUrl}">
+            <f:textarea name="description" value="${it.description}" />
+          </f:entry>
+        </table>
         <f:submit value="${%Submit}" />
       </form>
     </l:main-panel>

core/src/main/resources/hudson/model/Job/configure.jelly

@@ -39,7 +39,7 @@ THE SOFTWARE.
             <f:textbox name="name" value="${it.name}" />
           </f:entry>
         </j:if>
-        <f:entry title="${%Description}" help="/help/project-config/description.html">
+        <f:entry title="${%Description}" help="${app.markupFormatter.helpUrl}">
           <f:textarea name="description" value="${it.description}"/>
         </f:entry>