Show Pull Request button or status of latest PR in branch list (#6990)

* Show Pull Request button or status of latest PR in branch list

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Do not show pull request button on deleted branches

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Do not show commit divergence on deleted branches

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use XORMs Get instead of limit

* Links pull request ID and use smaller labels for displaying the pull request status

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Handle error when getting latest pull request

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Indent template

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Check error when loading issue

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

routers/repo/branch.go

@@ -24,13 +24,14 @@ const (
 
 // Branch contains the branch information
 type Branch struct {
-	Name          string
-	Commit        *git.Commit
-	IsProtected   bool
-	IsDeleted     bool
-	DeletedBranch *models.DeletedBranch
-	CommitsAhead  int
-	CommitsBehind int
+	Name              string
+	Commit            *git.Commit
+	IsProtected       bool
+	IsDeleted         bool
+	DeletedBranch     *models.DeletedBranch
+	CommitsAhead      int
+	CommitsBehind     int
+	LatestPullRequest *models.PullRequest
 }
 
 // Branches render repository branch page
@@ -181,12 +182,25 @@ func loadBranches(ctx *context.Context) []*Branch {
 			return nil
 		}
 
+		pr, err := models.GetLatestPullRequestByHeadInfo(ctx.Repo.Repository.ID, branchName)
+		if err != nil {
+			ctx.ServerError("GetLatestPullRequestByHeadInfo", err)
+			return nil
+		}
+		if pr != nil {
+			if err := pr.LoadIssue(); err != nil {
+				ctx.ServerError("pr.LoadIssue", err)
+				return nil
+			}
+		}
+
 		branches[i] = &Branch{
-			Name:          branchName,
-			Commit:        commit,
-			IsProtected:   isProtected,
-			CommitsAhead:  divergence.Ahead,
-			CommitsBehind: divergence.Behind,
+			Name:              branchName,
+			Commit:            commit,
+			IsProtected:       isProtected,
+			CommitsAhead:      divergence.Ahead,
+			CommitsBehind:     divergence.Behind,
+			LatestPullRequest: pr,
 		}
 	}