Add a Patch button to the diff view

src/main/scala/gitbucket/core/controller/RepositoryViewerController.scala

@@ -466,10 +466,10 @@ trait RepositoryViewerControllerBase extends ControllerBase {
     }
   })
 
-  get("/:owner/:repository/commit/:id/patch")(referrersOnly { repository =>
+  get("/:owner/:repository/patch/:id")(referrersOnly { repository =>
     try {
       using(Git.open(getRepositoryDir(repository.owner, repository.name))) { git =>
-        val diff = JGitUtil.getPatch(git, params("id"))
+        val diff = JGitUtil.getPatch(git, None, params("id"))
         contentType = formats("txt")
         diff
       }
@@ -478,6 +478,19 @@ trait RepositoryViewerControllerBase extends ControllerBase {
     }
   })
 
+  get("/:owner/:repository/patch/*...*")(referrersOnly { repository =>
+    try {
+      val Seq(fromId, toId) = multiParams("splat")
+      using(Git.open(getRepositoryDir(repository.owner, repository.name))) { git =>
+        val diff = JGitUtil.getPatch(git, Some(fromId), toId)
+        contentType = formats("txt")
+        diff
+      }
+    } catch {
+      case e: MissingObjectException => NotFound()
+    }
+  })
+
   post("/:owner/:repository/commit/:id/comment/new", commentForm)(readableUsersOnly { (form, repository) =>
     val id = params("id")
     createCommitComment(repository.owner, repository.name, id, context.loginAccount.get.userName, form.content,

src/main/scala/gitbucket/core/util/JGitUtil.scala

@@ -519,13 +519,13 @@ object JGitUtil {
     }.toMap
   }
 
-  def getPatch(git: Git, id: String): String = {
+  def getPatch(git: Git, from: Option[String], to: String): String = {
     val out = new ByteArrayOutputStream()
     val df = new DiffFormatter(out)
     df.setRepository(git.getRepository)
     df.setDiffComparator(RawTextComparator.DEFAULT)
     df.setDetectRenames(true)
-    df.format(getDiffEntries(git, None, id).head)
+    df.format(getDiffEntries(git, from, to).head)
     new String(out.toByteArray, "UTF-8")
   }
 

src/main/twirl/gitbucket/core/helper/diff.scala.html

@@ -10,9 +10,15 @@
 @import org.eclipse.jgit.diff.DiffEntry.ChangeType
 @if(showIndex){
   <div class="pull-right" style="margin-bottom: 10px;">
+    @if(oldCommitId.isEmpty && newCommitId.isDefined) {
+      <a href="@helpers.url(repository)/patch/@newCommitId" class="btn btn-default">Patch</a>
+    }
+    @if(oldCommitId.isDefined && newCommitId.isDefined) {
+      <a href="@helpers.url(repository)/patch/@oldCommitId...@newCommitId" class="btn btn-default">Patch</a>
+    }
     <div class="btn-group" data-toggle="buttons">
-      <input type="button" id="btn-unified" class="btn btn-default btn-small active" value="Unified">
+      <input type="button" id="btn-unified" class="btn btn-default active" value="Unified">
-      <input type="button" id="btn-split" class="btn btn-default btn-small" value="Split">
+      <input type="button" id="btn-split" class="btn btn-default" value="Split">
     </div>
   </div>
   Showing <a href="javascript:void(0);" id="toggle-file-list">@diffs.size changed @helpers.plural(diffs.size, "file")</a>