(refs #442)show compare/pull request link near branch link.

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

@@ -248,6 +248,7 @@ trait PullRequestsControllerBase extends ControllerBase {
   })
 
   get("/:owner/:repository/compare")(referrersOnly { forkedRepository =>
+    val headBranch:Option[String] = params.get("head")
     (forkedRepository.repository.originUserName, forkedRepository.repository.originRepositoryName) match {
       case (Some(originUserName), Some(originRepositoryName)) => {
         getRepository(originUserName, originRepositoryName, context.baseUrl).map { originRepository =>
@@ -255,8 +256,8 @@ trait PullRequestsControllerBase extends ControllerBase {
             Git.open(getRepositoryDir(originUserName, originRepositoryName)),
             Git.open(getRepositoryDir(forkedRepository.owner, forkedRepository.name))
           ){ (oldGit, newGit) =>
-            val oldBranch = JGitUtil.getDefaultBranch(oldGit, originRepository).get._2
-            val newBranch = JGitUtil.getDefaultBranch(newGit, forkedRepository).get._2
+            val newBranch = headBranch.getOrElse(JGitUtil.getDefaultBranch(newGit, forkedRepository).get._2)
+            val oldBranch = originRepository.branchList.find( _ == newBranch).getOrElse(JGitUtil.getDefaultBranch(oldGit, originRepository).get._2)
 
             redirect(s"/${forkedRepository.owner}/${forkedRepository.name}/compare/${originUserName}:${oldBranch}...${newBranch}")
           }
@@ -265,7 +266,7 @@ trait PullRequestsControllerBase extends ControllerBase {
       case _ => {
         using(Git.open(getRepositoryDir(forkedRepository.owner, forkedRepository.name))){ git =>
           JGitUtil.getDefaultBranch(git, forkedRepository).map { case (_, defaultBranch) =>
-            redirect(s"/${forkedRepository.owner}/${forkedRepository.name}/compare/${defaultBranch}...${defaultBranch}")
+            redirect(s"/${forkedRepository.owner}/${forkedRepository.name}/compare/${defaultBranch}...${headBranch.getOrElse(defaultBranch)}")
           } getOrElse {
             redirect(s"/${forkedRepository.owner}/${forkedRepository.name}")
           }

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

@@ -525,6 +525,7 @@ trait RepositoryViewerControllerBase extends ControllerBase {
               }, // groups of current user
               new JGitUtil.CommitInfo(lastModifiedCommit), // last modified commit
               files, readme, hasWritePermission(repository.owner, repository.name, context.loginAccount),
+              getPullRequestFromBranch(repository.owner, repository.name, revstr, repository.repository.defaultBranch),
               flash.get("info"), flash.get("error"))
           }
         } getOrElse NotFound

src/main/scala/gitbucket/core/service/PullRequestService.scala

@@ -83,6 +83,28 @@ trait PullRequestService { self: IssuesService =>
       .map { case (t1, t2) => t1 }
       .list
 
+  /**
+   * for repository viewer.
+   * 1. find pull request from from `branch` to othre branch on same repository
+   *   1. return if exists pull request to `defaultBranch`
+   *   2. return if exists pull request to othre branch
+   * 2. return None
+   */
+  def getPullRequestFromBranch(userName: String, repositoryName: String, branch: String, defaultBranch: String)
+                              (implicit s: Session): Option[(PullRequest, Issue)] =
+    PullRequests
+      .innerJoin(Issues).on { (t1, t2) => t1.byPrimaryKey(t2.userName, t2.repositoryName, t2.issueId) }
+      .filter { case (t1, t2) =>
+        (t1.requestUserName       === userName.bind) &&
+        (t1.requestRepositoryName === repositoryName.bind) &&
+        (t1.requestBranch         === branch.bind) &&
+        (t1.userName              === userName.bind) &&
+        (t1.repositoryName        === repositoryName.bind) &&
+        (t2.closed                === false.bind)
+      }
+      .sortBy{ case (t1, t2) => t1.branch =!= defaultBranch.bind }
+      .firstOption
+
   /**
    * Fetch pull request contents into refs/pull/${issueId}/head and update pull request table.
    */

src/main/twirl/gitbucket/core/repo/files.scala.html

@@ -6,6 +6,7 @@
   files: List[gitbucket.core.util.JGitUtil.FileInfo],
   readme: Option[(List[String], String)],
   hasWritePermission: Boolean,
+  branchPullRequest: Option[(gitbucket.core.model.PullRequest, gitbucket.core.model.Issue)],
   info: Option[Any] = None,
   error: Option[Any] = None)(implicit context: gitbucket.core.controller.Context)
 @import context._
@@ -13,6 +14,11 @@
 @html.main(s"${repository.owner}/${repository.name}", Some(repository)) {
   @html.menu("code", repository, Some(branch), pathList.isEmpty, groupNames.isEmpty, info, error){
     <div class="head">
+      @branchPullRequest.map{ case (pullRequest, issue) =>
+        <a href="@url(repository)/pull/@pullRequest.issueId" class="btn btn-pullrequest-branch btn-mini" title="@issue.title" data-toggle="tooltip">#@pullRequest.issueId</a>
+      }.getOrElse{
+        <a href="@url(repository)/compare?head=@urlEncode(encodeRefName(branch))" class="btn btn-success btn-mini"><i class="icon-white icon-retweet" data-toggle="tooltip" title="Compare, review, create a pull request"></i></a>
+      }
       @helper.html.branchcontrol(
         branch,
         repository,

src/main/webapp/assets/common/css/gitbucket.css

@@ -701,6 +701,12 @@ span.simplified-path {
   padding-left: 16px;
 }
 
+.btn-pullrequest-branch{
+  background: none;
+  border: 1px solid #0088cc;
+  color: #0088cc;
+}
+
 /****************************************************************************/
 /* nav pulls group */
 /****************************************************************************/

src/test/scala/gitbucket/core/service/PullRequestServiceSpec.scala

@@ -0,0 +1,33 @@
+package gitbucket.core.service
+
+import gitbucket.core.model._
+import gitbucket.core.model.Profile._
+
+import org.specs2.mutable.Specification
+
+class PullRequestServiceSpec extends Specification with ServiceSpecBase with PullRequestService with IssuesService {
+  def swap(r: (Issue, PullRequest)) = (r._2 -> r._1)
+  "PullRequestService.getPullRequestFromBranch" should {
+    """
+    |return pull request if exists pull request from `branch` to `defaultBranch` and not closed.
+    |return pull request if exists pull request from `branch` to othre branch and not closed.
+    |return None if all pull request is closed""".stripMargin.trim in { withTestDB { implicit se =>
+      generateNewUserWithDBRepository("user1", "repo1")
+      generateNewUserWithDBRepository("user1", "repo2")
+      generateNewUserWithDBRepository("user2", "repo1")
+      generateNewPullRequest("user1/repo1/master", "user1/repo1/head2") // not target branch
+      generateNewPullRequest("user1/repo1/head1", "user1/repo1/master") // not target branch ( swap from, to )
+      generateNewPullRequest("user1/repo1/master", "user2/repo1/head1") // othre user
+      generateNewPullRequest("user1/repo1/master", "user1/repo2/head1") // othre repository
+      val r1 = swap(generateNewPullRequest("user1/repo1/master2", "user1/repo1/head1"))
+      val r2 = swap(generateNewPullRequest("user1/repo1/master", "user1/repo1/head1"))
+      val r3 = swap(generateNewPullRequest("user1/repo1/master4", "user1/repo1/head1"))
+      getPullRequestFromBranch("user1", "repo1", "head1", "master") must_== Some(r2)
+      updateClosed("user1", "repo1", r2._1.issueId, true)
+      getPullRequestFromBranch("user1", "repo1", "head1", "master").get must beOneOf(r1, r2)
+      updateClosed("user1", "repo1", r1._1.issueId, true)
+      updateClosed("user1", "repo1", r3._1.issueId, true)
+      getPullRequestFromBranch("user1", "repo1", "head1", "master") must beNone
+    } }
+  }
+}

src/test/scala/gitbucket/core/service/ServiceSpecBase.scala

@@ -39,7 +39,7 @@ trait ServiceSpecBase {
     with CommitStatusService (){}
 
   def generateNewUserWithDBRepository(userName:String, repositoryName:String)(implicit s:Session):Account = {
-    val ac = generateNewAccount(userName)
+    val ac = AccountService.getAccountByUserName(userName).getOrElse(generateNewAccount(userName))
     dummyService.createRepository(repositoryName, userName, None, false)
     ac
   }