diff --git a/cmd/web.go b/cmd/web.go
index 9942f19a50c7c..01ca51a00a41e 100644
--- a/cmd/web.go
+++ b/cmd/web.go
@@ -536,6 +536,8 @@ func runWeb(ctx *cli.Context) error {
 			m.Get("/releases", repo.Releases)
 			m.Get("/^:type(issues|pulls)$", repo.RetrieveLabels, repo.Issues)
 			m.Get("/^:type(issues|pulls)$/:index", repo.ViewIssue)
+			m.Get("/reviews", repo.RetrieveLabels, repo.Reviews)
+			m.Get("/reviews/:index", context.RepoRef(), repo.SetEditorconfigIfExists, repo.ViewReview)
 			m.Get("/labels/", repo.RetrieveLabels, repo.Labels)
 			m.Get("/milestones", repo.Milestones)
 		}, context.RepoRef())
@@ -564,6 +566,12 @@ func runWeb(ctx *cli.Context) error {
 			m.Post("/merge", reqRepoWriter, repo.MergePullRequest)
 		}, repo.MustAllowPulls)
 
+		m.Group("/reviews/:index", func() {
+			m.Get("/commits", context.RepoRef(), repo.ViewReviewCommits)
+			m.Get("/files", context.RepoRef(), repo.SetEditorconfigIfExists, repo.SetDiffViewStyle, repo.ViewReviewFiles)
+			m.Post("/merge", reqRepoWriter, repo.MergePullRequest)
+		}, repo.MustAllowReviews)
+
 		m.Group("", func() {
 			m.Get("/src/*", repo.SetEditorconfigIfExists, repo.Home)
 			m.Get("/raw/*", repo.SingleDownload)
diff --git a/models/issue.go b/models/issue.go
index ac50d2dfba313..4fe642d13e5ae 100644
--- a/models/issue.go
+++ b/models/issue.go
@@ -7,6 +7,7 @@ package models
 import (
 	"errors"
 	"fmt"
+	"strconv"
 	"strings"
 	"time"
 
@@ -29,6 +30,7 @@ type Issue struct {
 	RepoID          int64       `xorm:"INDEX UNIQUE(repo_index)"`
 	Repo            *Repository `xorm:"-"`
 	Index           int64       `xorm:"UNIQUE(repo_index)"` // Index in one repository.
+	Revision        string      `xorm:"-"`                  // revision for appraise requests
 	PosterID        int64       `xorm:"INDEX"`
 	Poster          *User       `xorm:"-"`
 	Title           string      `xorm:"name"`
@@ -43,6 +45,7 @@ type Issue struct {
 	IsClosed        bool         `xorm:"INDEX"`
 	IsRead          bool         `xorm:"-"`
 	IsPull          bool         `xorm:"INDEX"` // Indicates whether is a pull request or not.
+	IsReview        bool         `xorm:"-"`     // Indicates whether is a review or not.
 	PullRequest     *PullRequest `xorm:"-"`
 	NumComments     int
 
@@ -236,6 +239,14 @@ func (issue *Issue) APIFormat() *api.Issue {
 	return apiIssue
 }
 
+// GetIndex returns string index for templates
+func (issue *Issue) GetIndex() string {
+	if issue.IsReview {
+		return issue.Revision
+	}
+	return strconv.Itoa(int(issue.Index))
+}
+
 // HashTag returns unique hash tag for issue.
 func (issue *Issue) HashTag() string {
 	return "issue-" + com.ToStr(issue.ID)
@@ -1734,4 +1745,3 @@ func DeleteMilestoneByRepoID(repoID, id int64) error {
 	}
 	return sess.Commit()
 }
-
diff --git a/models/issue_comment.go b/models/issue_comment.go
index e9a401b864299..00b8c58242ee5 100644
--- a/models/issue_comment.go
+++ b/models/issue_comment.go
@@ -6,6 +6,7 @@ package models
 
 import (
 	"fmt"
+	gotemplate "html/template"
 	"strings"
 	"time"
 
@@ -61,6 +62,10 @@ type Comment struct {
 	Content         string `xorm:"TEXT"`
 	RenderedContent string `xorm:"-"`
 
+	FileContent    gotemplate.HTML `xorm:"-"`
+	LineNums       gotemplate.HTML `xorm:"-"`
+	HighlightClass string          `xorm:"-"`
+
 	Created     time.Time `xorm:"-"`
 	CreatedUnix int64     `xorm:"INDEX"`
 	Updated     time.Time `xorm:"-"`
diff --git a/models/repo.go b/models/repo.go
index c2480d9ddbf58..467768e22a8e1 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -189,6 +189,7 @@ type Repository struct {
 	NumPulls            int
 	NumClosedPulls      int
 	NumOpenPulls        int `xorm:"-"`
+	NumOpenReviews      int `xorm:"-"`
 	NumMilestones       int `xorm:"NOT NULL DEFAULT 0"`
 	NumClosedMilestones int `xorm:"NOT NULL DEFAULT 0"`
 	NumOpenMilestones   int `xorm:"-"`
@@ -211,6 +212,7 @@ type Repository struct {
 	ExternalTrackerStyle  string
 	ExternalMetas         map[string]string `xorm:"-"`
 	EnablePulls           bool              `xorm:"NOT NULL DEFAULT true"`
+	EnableReviews         bool              `xorm:"NOT NULL DEFAULT true"`
 
 	IsFork   bool        `xorm:"INDEX NOT NULL DEFAULT false"`
 	ForkID   int64       `xorm:"INDEX"`
@@ -485,6 +487,11 @@ func (repo *Repository) AllowsPulls() bool {
 	return repo.CanEnablePulls() && repo.EnablePulls
 }
 
+// AllowsReviews returns true if repository meets the requirements of accepting pulls and has them enabled.
+func (repo *Repository) AllowsReviews() bool {
+	return repo.EnableReviews
+}
+
 // CanEnableEditor returns true if repository meets the requirements of web editor.
 func (repo *Repository) CanEnableEditor() bool {
 	return !repo.IsMirror
@@ -1035,15 +1042,16 @@ func CreateRepository(u *User, opts CreateRepoOptions) (_ *Repository, err error
 	}
 
 	repo := &Repository{
-		OwnerID:      u.ID,
-		Owner:        u,
-		Name:         opts.Name,
-		LowerName:    strings.ToLower(opts.Name),
-		Description:  opts.Description,
-		IsPrivate:    opts.IsPrivate,
-		EnableWiki:   true,
-		EnableIssues: true,
-		EnablePulls:  true,
+		OwnerID:       u.ID,
+		Owner:         u,
+		Name:          opts.Name,
+		LowerName:     strings.ToLower(opts.Name),
+		Description:   opts.Description,
+		IsPrivate:     opts.IsPrivate,
+		EnableWiki:    true,
+		EnableIssues:  true,
+		EnablePulls:   true,
+		EnableReviews: true,
 	}
 
 	sess := x.NewSession()
diff --git a/modules/auth/repo_form.go b/modules/auth/repo_form.go
index dda1f9d252617..119b232c0d77d 100644
--- a/modules/auth/repo_form.go
+++ b/modules/auth/repo_form.go
@@ -104,6 +104,7 @@ type RepoSettingForm struct {
 	TrackerURLFormat      string
 	TrackerIssueStyle     string
 	EnablePulls           bool
+	EnableReviews         bool
 }
 
 // Validate valideates the fields
@@ -267,7 +268,7 @@ type NewReleaseForm struct {
 	Content    string
 	Draft      string
 	Prerelease bool
-	Files   []string
+	Files      []string
 }
 
 // Validate valideates the fields
@@ -281,7 +282,7 @@ type EditReleaseForm struct {
 	Content    string `form:"content"`
 	Draft      string `form:"draft"`
 	Prerelease bool   `form:"prerelease"`
-	Files   []string
+	Files      []string
 }
 
 // Validate valideates the fields
diff --git a/modules/context/repo.go b/modules/context/repo.go
index 338a78cb93cea..2acbdf7b877ca 100644
--- a/modules/context/repo.go
+++ b/modules/context/repo.go
@@ -15,6 +15,8 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"github.com/Unknwon/com"
+	"github.com/google/git-appraise/repository"
+	"github.com/google/git-appraise/review"
 	editorconfig "gopkg.in/editorconfig/editorconfig-core-go.v1"
 	macaron "gopkg.in/macaron.v1"
 )
@@ -286,6 +288,15 @@ func RepoAssignment(args ...bool) macaron.Handler {
 		ctx.Data["Branches"] = brs
 		ctx.Data["BrancheCount"] = len(brs)
 
+		// Count open reviews
+		if repo.AllowsReviews() {
+			appraiseRepo, err := repository.NewGitRepo(ctx.Repo.GitRepo.Path)
+			if err != nil {
+				ctx.Handle(500, "OpenGitRepository", err)
+			}
+			ctx.Repo.Repository.NumOpenReviews = len(review.ListOpen(appraiseRepo))
+		}
+
 		// If not branch selected, try default one.
 		// If default branch doesn't exists, fall back to some other branch.
 		if len(ctx.Repo.BranchName) == 0 {
diff --git a/options/locale/locale_en-US.ini b/options/locale/locale_en-US.ini
index 9b9e25ba812c3..3d875e7f6e90e 100644
--- a/options/locale/locale_en-US.ini
+++ b/options/locale/locale_en-US.ini
@@ -459,6 +459,7 @@ branches = Branches
 tags = Tags
 issues = Issues
 pulls = Pull Requests
+reviews = Reviews
 labels = Labels
 milestones = Milestones
 commits = Commits
@@ -708,6 +709,7 @@ settings.tracker_issue_style.numeric = Numeric
 settings.tracker_issue_style.alphanumeric = Alphanumeric
 settings.tracker_url_format_desc = You can use placeholder <code>{user} {repo} {index}</code> for user name, repository name and issue index.
 settings.pulls_desc = Enable pull requests to accept public contributions
+settings.reviews_desc = Enable appraise reviews
 settings.danger_zone = Danger Zone
 settings.new_owner_has_same_repo = The new owner already has a repository with same name. Please choose another name.
 settings.convert = Convert To Regular Repository
diff --git a/public/css/index.css b/public/css/index.css
index 7c84cf8517aa9..11e70f9efa6f5 100644
--- a/public/css/index.css
+++ b/public/css/index.css
@@ -1315,64 +1315,64 @@ footer .ui.language .menu {
 .repository.file.list #file-content .view-raw img {
   padding: 5px 5px 0 5px;
 }
-.repository.file.list #file-content .code-view * {
+.code-view * {
   font-size: 12px;
   font-family: Consolas, "Liberation Mono", Menlo, Courier, monospace;
   line-height: 20px;
 }
-.repository.file.list #file-content .code-view table {
+.code-view table {
   width: 100%;
 }
-.repository.file.list #file-content .code-view .lines-num {
+.code-view .lines-num {
   vertical-align: top;
   text-align: right;
   color: #999;
   background: #f5f5f5;
   width: 1%;
 }
-.repository.file.list #file-content .code-view .lines-num span {
+.code-view .lines-num span {
   line-height: 20px;
   padding: 0 10px;
   cursor: pointer;
   display: block;
 }
-.repository.file.list #file-content .code-view .lines-num,
-.repository.file.list #file-content .code-view .lines-code {
+.code-view .lines-num,
+.code-view .lines-code {
   padding: 0;
 }
-.repository.file.list #file-content .code-view .lines-num pre,
-.repository.file.list #file-content .code-view .lines-code pre,
-.repository.file.list #file-content .code-view .lines-num ol,
-.repository.file.list #file-content .code-view .lines-code ol,
-.repository.file.list #file-content .code-view .lines-num .hljs,
-.repository.file.list #file-content .code-view .lines-code .hljs {
+.code-view .lines-num pre,
+.code-view .lines-code pre,
+.code-view .lines-num ol,
+.code-view .lines-code ol,
+.code-view .lines-num .hljs,
+.code-view .lines-code .hljs {
   background-color: white;
   margin: 0;
   padding: 0 !important;
 }
-.repository.file.list #file-content .code-view .lines-num pre li,
-.repository.file.list #file-content .code-view .lines-code pre li,
-.repository.file.list #file-content .code-view .lines-num ol li,
-.repository.file.list #file-content .code-view .lines-code ol li,
-.repository.file.list #file-content .code-view .lines-num .hljs li,
-.repository.file.list #file-content .code-view .lines-code .hljs li {
+.code-view .lines-num pre li,
+.code-view .lines-code pre li,
+.code-view .lines-num ol li,
+.code-view .lines-code ol li,
+.code-view .lines-num .hljs li,
+.code-view .lines-code .hljs li {
   display: inline-block;
   width: 100%;
 }
-.repository.file.list #file-content .code-view .lines-num pre li.active,
-.repository.file.list #file-content .code-view .lines-code pre li.active,
-.repository.file.list #file-content .code-view .lines-num ol li.active,
-.repository.file.list #file-content .code-view .lines-code ol li.active,
-.repository.file.list #file-content .code-view .lines-num .hljs li.active,
-.repository.file.list #file-content .code-view .lines-code .hljs li.active {
+.code-view .lines-num pre li.active,
+.code-view .lines-code pre li.active,
+.code-view .lines-num ol li.active,
+.code-view .lines-code ol li.active,
+.code-view .lines-num .hljs li.active,
+.code-view .lines-code .hljs li.active {
   background: #ffffdd;
 }
-.repository.file.list #file-content .code-view .lines-num pre li:before,
-.repository.file.list #file-content .code-view .lines-code pre li:before,
-.repository.file.list #file-content .code-view .lines-num ol li:before,
-.repository.file.list #file-content .code-view .lines-code ol li:before,
-.repository.file.list #file-content .code-view .lines-num .hljs li:before,
-.repository.file.list #file-content .code-view .lines-code .hljs li:before {
+.code-view .lines-num pre li:before,
+.code-view .lines-code pre li:before,
+.code-view .lines-num ol li:before,
+.code-view .lines-code ol li:before,
+.code-view .lines-num .hljs li:before,
+.code-view .lines-code .hljs li:before {
   content: ' ';
 }
 .repository.file.list .sidebar {
@@ -1514,6 +1514,11 @@ footer .ui.language .menu {
   font-size: 2.3rem;
   margin-bottom: 5px;
 }
+.repository.view.issue .title .revision {
+  top: -1rem;
+  padding-top: 0;
+  padding-bottom: 5px;
+}
 .repository.view.issue .title h1 .ui.input {
   font-size: 0.5em;
   vertical-align: top;
@@ -1531,6 +1536,7 @@ footer .ui.language .menu {
 }
 .repository.view.issue .title .label {
   margin-right: 10px;
+  margin-left: 0px;
 }
 .repository.view.issue .title .edit-zone {
   margin-top: 10px;
@@ -2265,6 +2271,13 @@ footer .ui.language .menu {
   font-weight: bold;
   margin: 0 6px;
 }
+.issue.list > .item .title.review {
+  margin: 0 0;
+}
+.issue.list > .item .revision {
+  font-size: 12px;
+  color: #aaa;
+}
 .issue.list > .item .title:hover {
   color: #000;
 }
diff --git a/public/less/_repository.less b/public/less/_repository.less
index 0babcedf395ee..ad88684867146 100644
--- a/public/less/_repository.less
+++ b/public/less/_repository.less
@@ -253,53 +253,6 @@
 					padding: 5px 5px 0 5px;
 				}
 			}
-
-			.code-view {
-				* {
-					font-size: 12px;
-					font-family: Consolas, "Liberation Mono", Menlo, Courier, monospace;
-					line-height: 20px;
-				}
-
-				table {
-					width: 100%;
-				}
-				.lines-num {
-					vertical-align: top;
-					text-align: right;
-					color: #999;
-					background: #f5f5f5;
-					width: 1%;
-
-					span {
-						line-height: 20px;
-						padding: 0 10px;
-						cursor: pointer;
-						display: block;
-					}
-				}
-				.lines-num,
-				.lines-code {
-					padding: 0;
-					pre,
-					ol,
-					.hljs {
-						background-color: white;
-						margin: 0;
-						padding: 0 !important;
-						li {
-							display: inline-block;
-							width: 100%;
-							&.active {
-								background: #ffffdd;
-							}
-							&:before {
-								content: ' ';
-							}
-						}
-					}
-				}
-			}
 		}
 
 		.sidebar {
@@ -1483,3 +1436,50 @@
 	}
 	.generate-tab-size(@n, (@i + 1));
 }
+
+.code-view {
+	* {
+		font-size: 12px;
+		font-family: Consolas, "Liberation Mono", Menlo, Courier, monospace;
+		line-height: 20px;
+	}
+
+	table {
+		width: 100%;
+	}
+	.lines-num {
+		vertical-align: top;
+		text-align: right;
+		color: #999;
+		background: #f5f5f5;
+		width: 1%;
+
+		span {
+			line-height: 20px;
+			padding: 0 10px;
+			cursor: pointer;
+			display: block;
+		}
+	}
+	.lines-num,
+	.lines-code {
+		padding: 0;
+		pre,
+		ol,
+		.hljs {
+			background-color: white;
+			margin: 0;
+			padding: 0 !important;
+			li {
+				display: inline-block;
+				width: 100%;
+				&.active {
+					background: #ffffdd;
+				}
+				&:before {
+					content: ' ';
+				}
+			}
+		}
+	}
+}
diff --git a/routers/init.go b/routers/init.go
index 697f33835cde1..b58467e4832c9 100644
--- a/routers/init.go
+++ b/routers/init.go
@@ -24,7 +24,7 @@ func checkRunMode() {
 	switch setting.Cfg.Section("").Key("RUN_MODE").String() {
 	case "prod":
 		macaron.Env = macaron.PROD
-		macaron.ColorLog = false
+		macaron.ColorLog = true
 		setting.ProdMode = true
 	default:
 		git.Debug = true
diff --git a/routers/repo/reviews.go b/routers/repo/reviews.go
new file mode 100644
index 0000000000000..a5bd2961e9b17
--- /dev/null
+++ b/routers/repo/reviews.go
@@ -0,0 +1,481 @@
+// Copyright 2017 The Gitea. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package repo
+
+import (
+	"bytes"
+	"container/list"
+	"fmt"
+	gotemplate "html/template"
+	"log"
+	"path"
+	"strconv"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/highlight"
+	"code.gitea.io/gitea/modules/markdown"
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/Unknwon/com"
+	"github.com/google/git-appraise/repository"
+	"github.com/google/git-appraise/review"
+)
+
+const (
+	tplReviews base.TplName = "repo/review/list"
+)
+
+// MustAllowReviews check if repository enable reviews
+func MustAllowReviews(ctx *context.Context) {
+	if !ctx.Repo.Repository.AllowsReviews() {
+		ctx.Handle(404, "MustAllowReviews", nil)
+		return
+	}
+}
+
+// Reviews render issues page
+func Reviews(ctx *context.Context) {
+	repo, err := repository.NewGitRepo(ctx.Repo.GitRepo.Path)
+	if err != nil {
+		ctx.Handle(500, "OpenGitRepository", err)
+	}
+	total := review.ListAll(repo)
+
+	viewType := ctx.Query("type")
+	sortType := ctx.Query("sort")
+	selectLabels := ctx.Query("labels")
+	milestoneID := ctx.QueryInt64("milestone")
+	assigneeID := ctx.QueryInt64("assignee")
+	isShowClosed := ctx.Query("state") == "closed"
+
+	issues := []*models.Issue{}
+	stat := models.IssueStats{OpenCount: 0, ClosedCount: 0, AllCount: 0}
+
+	for _, review := range total {
+		details, _ := review.Details()
+		notes, _ := details.GetAnalysesNotes()
+		for _, note := range notes {
+			log.Print(note)
+		}
+
+		timestamp, _ := strconv.Atoi(review.Request.Timestamp)
+		time := time.Unix(int64(timestamp), 0)
+
+		closed := false
+		if review.Submitted || review.Request.TargetRef == "" {
+			closed = true
+			stat.ClosedCount++
+		} else {
+			stat.OpenCount++
+		}
+		readed := false
+		if (review.Resolved != nil && *review.Resolved) || review.Request.TargetRef == "" {
+			readed = true
+		}
+
+		user, err := models.GetUserByEmail(review.Request.Requester)
+		if err != nil {
+			user = &models.User{Name: review.Request.Requester}
+		}
+
+		issue := models.Issue{
+			Revision:    review.Revision,
+			Title:       strings.Split(review.Request.Description, "\n\n")[0],
+			Poster:      user,
+			Created:     time,
+			CreatedUnix: int64(timestamp),
+			Labels:      []*models.Label{},
+			IsClosed:    closed,
+			IsRead:      readed,
+			IsReview:    true,
+		}
+
+		if closed && isShowClosed {
+			issues = append(issues, &issue)
+		}
+		if !closed && !isShowClosed {
+			issues = append(issues, &issue)
+		}
+		stat.AllCount++
+	}
+
+	ctx.Data["Title"] = ctx.Tr("repo.reviews")
+	ctx.Data["PageIsReviewList"] = true
+	// ctx.Data["Page"] = 0
+	ctx.Data["Issues"] = issues
+	ctx.Data["Milestones"], err = models.GetMilestonesByRepoID(ctx.Repo.Repository.ID)
+	if err != nil {
+		ctx.Handle(500, "GetAllRepoMilestones", err)
+		return
+	}
+
+	// Get assignees.
+	ctx.Data["Assignees"], err = ctx.Repo.Repository.GetAssignees()
+	if err != nil {
+		ctx.Handle(500, "GetAssignees", err)
+		return
+	}
+	ctx.Data["SelectLabels"] = com.StrTo(selectLabels).MustInt64()
+	ctx.Data["IssueStats"] = stat
+	ctx.Data["ViewType"] = viewType
+	ctx.Data["SortType"] = sortType
+	ctx.Data["MilestoneID"] = milestoneID
+	ctx.Data["AssigneeID"] = assigneeID
+	ctx.Data["IsShowClosed"] = isShowClosed
+	if isShowClosed {
+		ctx.Data["State"] = "closed"
+	} else {
+		ctx.Data["State"] = "open"
+	}
+	ctx.HTML(200, tplIssues)
+}
+
+func prepareReviewInfo(ctx *context.Context) (*repository.GitRepo, *review.Summary, *review.Review, *models.Issue) {
+	ctx.Data["PageIsReviewList"] = true
+
+	repo, err := repository.NewGitRepo(ctx.Repo.GitRepo.Path)
+	if err != nil {
+		ctx.Handle(500, "OpenGitRepository", err)
+	}
+	reviewSummary, err := review.GetSummary(repo, ctx.Params(":index"))
+	if err != nil {
+		ctx.Handle(500, "GetReviewSummary", err)
+	}
+	reviewDetails, err := reviewSummary.Details()
+	if err != nil {
+		ctx.Handle(500, "GetReview", err)
+	}
+
+	issueUser, _ := models.GetUserByEmail(reviewDetails.Request.Requester)
+	issueCreatedTimestamp, _ := strconv.Atoi(reviewDetails.Request.Timestamp)
+	issueCreated := time.Unix(int64(issueCreatedTimestamp), 0)
+
+	closed := false
+	if reviewDetails.Submitted || reviewDetails.Request.TargetRef == "" {
+		closed = true
+	}
+	readed := false
+	if (reviewDetails.Resolved != nil && *reviewDetails.Resolved) || reviewDetails.Request.TargetRef == "" {
+		readed = true
+	}
+
+	issue := &models.Issue{
+		ID:          0,
+		Index:       0,
+		Revision:    reviewDetails.Revision,
+		Title:       strings.Split(reviewDetails.Request.Description, "\n\n")[0],
+		Content:     reviewDetails.Request.Description,
+		Poster:      issueUser,
+		Created:     issueCreated,
+		Labels:      []*models.Label{},
+		IsClosed:    closed,
+		IsRead:      readed,
+		IsReview:    true,
+		NumComments: len(reviewDetails.Comments),
+		Comments:    []*models.Comment{},
+		PullRequest: &models.PullRequest{
+			HasMerged: reviewDetails.Submitted,
+		},
+	}
+
+	issue.RenderedContent = string(markdown.Render([]byte(issue.Content), ctx.Repo.RepoLink,
+		ctx.Repo.Repository.ComposeMetas()))
+
+	ctx.Data["HasMerged"] = reviewDetails.Submitted
+
+	reviewCommits, err := repo.ListCommitsBetween(reviewDetails.Request.TargetRef, reviewDetails.Request.ReviewRef)
+	if err != nil {
+		ctx.Handle(500, "ListCommitsBetween", err)
+	}
+
+	startCommitID, err := reviewDetails.GetBaseCommit()
+	if err != nil {
+		ctx.Handle(500, "GetBaseCommit", err)
+	}
+
+	ctx.Data["HeadTarget"] = reviewDetails.Request.ReviewRef
+	ctx.Data["BaseTarget"] = reviewDetails.Request.TargetRef
+	ctx.Data["Title"] = strings.Split(reviewDetails.Request.Description, "\n\n")[0]
+	ctx.Data["Issue"] = issue
+	ctx.Data["IsIssueOwner"] = ctx.Repo.IsWriter() || (ctx.IsSigned && issue.IsPoster(ctx.User.ID))
+
+	ctx.Data["NumCommits"], err = ctx.Repo.GitRepo.CommitsCountBetween(startCommitID, reviewCommits[len(reviewCommits)-1])
+	if err != nil {
+		ctx.Handle(500, "Repo.GitRepo.CommitsCountBetween", err)
+	}
+	ctx.Data["NumFiles"], err = ctx.Repo.GitRepo.FilesCountBetween(startCommitID, reviewCommits[len(reviewCommits)-1])
+	if err != nil {
+		ctx.Handle(500, "Repo.GitRepo.FilesCountBetween", err)
+	}
+
+	return repo, reviewSummary, reviewDetails, issue
+}
+
+// ViewReview render issue view page
+func ViewReview(ctx *context.Context) {
+	ctx.Data["RequireHighlightJS"] = true
+	ctx.Data["RequireDropzone"] = true
+
+	repo, _, reviewDetails, issue := prepareReviewInfo(ctx)
+
+	MustAllowReviews(ctx)
+	if ctx.Written() {
+		return
+	}
+
+	ctx.Data["PageIsPullConversation"] = true
+	//
+	// repo := ctx.Repo.Repository
+	//
+	// if issue.PullRequest.HasMerged {
+	// 	ctx.Data["DisableStatusChange"] = issue.PullRequest.HasMerged
+	// 	PrepareMergedViewPullInfo(ctx, issue)
+	// } else {
+	// 	PrepareViewPullInfo(ctx, issue)
+	// }
+	// if ctx.Written() {
+	// 	return
+	// }
+
+	// // Metas.
+	// // Check labels.
+	// labelIDMark := make(map[int64]bool)
+	// for i := range issue.Labels {
+	// 	labelIDMark[issue.Labels[i].ID] = true
+	// }
+	// labels, err := models.GetLabelsByRepoID(repo.ID, "")
+	// if err != nil {
+	// 	ctx.Handle(500, "GetLabelsByRepoID", err)
+	// 	return
+	// }
+	// hasSelected := false
+	// for i := range labels {
+	// 	if labelIDMark[labels[i].ID] {
+	// 		labels[i].IsChecked = true
+	// 		hasSelected = true
+	// 	}
+	// }
+	// ctx.Data["HasSelectedLabel"] = hasSelected
+	// ctx.Data["Labels"] = labels
+	//
+	// // Check milestone and assignee.
+	// if ctx.Repo.IsWriter() {
+	// 	RetrieveRepoMilestonesAndAssignees(ctx, repo)
+	// 	if ctx.Written() {
+	// 		return
+	// 	}
+	// }
+
+	// if ctx.IsSigned {
+	// 	// Update issue-user.
+	// 	if err = issue.ReadBy(ctx.User.ID); err != nil {
+	// 		ctx.Handle(500, "ReadBy", err)
+	// 		return
+	// 	}
+	// }
+	//
+	// var (
+	// 	tag          models.CommentTag
+	// 	ok           bool
+	// 	marked       = make(map[int64]models.CommentTag)
+	// var comment *models.Comment
+	participants := make([]*models.User, 1, 10)
+	// )
+	//
+	// // Render comments and and fetch participants.
+	participants[0] = issue.Poster
+	for _, c := range reviewDetails.Comments {
+		log.Print(c.Comment, c.Hash)
+		reviewComment := models.Comment{}
+
+		commentUser, _ := models.GetUserByEmail(c.Comment.Author)
+		reviewComment.Poster = commentUser
+
+		reviewComment.Content = c.Comment.Description
+
+		reviewComment.RenderedContent = string(markdown.Render([]byte(reviewComment.Content), ctx.Repo.RepoLink,
+			ctx.Repo.Repository.ComposeMetas()))
+
+		commentCreatedTimestamp, _ := strconv.Atoi(c.Comment.Timestamp)
+		commentCreated := time.Unix(int64(commentCreatedTimestamp), 0)
+		reviewComment.Created = commentCreated
+		// c.Comment.Location.Path
+		// c.Comment.Location.Commit
+		if c.Comment.Location != nil && c.Comment.Location.Range != nil {
+			reviewComment.Line = int64(c.Comment.Location.Range.StartLine)
+
+			contents, err := repo.Show(c.Comment.Location.Commit, c.Comment.Location.Path)
+			if err != nil {
+				continue
+			}
+			lines := strings.Split(contents, "\n")
+			if c.Comment.Location.Range.StartLine <= uint32(len(lines)) {
+				var firstLine uint32
+				lastLine := c.Comment.Location.Range.StartLine
+				if lastLine > 5 {
+					firstLine = lastLine - 5
+				}
+
+				var output bytes.Buffer
+				fileLines := lines[firstLine:lastLine]
+				for index, line := range fileLines {
+					output.WriteString(fmt.Sprintf(`<li class="L%d" rel="L%d">%s</li>`, index+1, index+1, gotemplate.HTMLEscapeString(line)) + "\n")
+				}
+				reviewComment.FileContent = gotemplate.HTML(output.String())
+
+				output.Reset()
+				for i := 0; i < len(fileLines); i++ {
+					output.WriteString(fmt.Sprintf(`<span id="L%d">%d</span>`, i+int(firstLine)+1, i+int(firstLine)+1))
+				}
+				reviewComment.LineNums = gotemplate.HTML(output.String())
+
+				reviewComment.HighlightClass = highlight.FileNameToHighlightClass(c.Comment.Location.Path)
+			}
+		}
+
+		//
+		// 		// Check tag.
+		// 		tag, ok = marked[comment.PosterID]
+		// 		if ok {
+		// 			comment.ShowTag = tag
+		// 			continue
+		// 		}
+		//
+		if ctx.Repo.Repository.IsOwnedBy(reviewComment.Poster.ID) ||
+			(ctx.Repo.Repository.Owner.IsOrganization() && ctx.Repo.Repository.Owner.IsOwnedBy(reviewComment.Poster.ID)) {
+			reviewComment.ShowTag = models.CommentTagOwner
+		} else if reviewComment.Poster.IsWriterOfRepo(ctx.Repo.Repository) {
+			reviewComment.ShowTag = models.CommentTagWriter
+		} else if reviewComment.Poster.ID == issue.Poster.ID {
+			reviewComment.ShowTag = models.CommentTagPoster
+		}
+		//
+		// 		marked[comment.PosterID] = comment.ShowTag
+		//
+		isAdded := false
+		for j := range participants {
+			if reviewComment.Poster.ID == participants[j].ID {
+				isAdded = true
+				break
+			}
+		}
+		if !isAdded && !issue.IsPoster(reviewComment.Poster.ID) {
+			participants = append(participants, reviewComment.Poster)
+		}
+		// }
+		//
+		// pull := issue.PullRequest
+		// canDelete := false
+
+		// if ctx.IsSigned && pull.HeadBranch != "master" {
+		//
+		// 	if err := pull.GetHeadRepo(); err != nil {
+		// 		log.Error(4, "GetHeadRepo: %v", err)
+		// 	} else if ctx.User.IsWriterOfRepo(pull.HeadRepo) {
+		// 		canDelete = true
+		// 		deleteBranchURL := pull.HeadRepo.Link() + "/branches/" + pull.HeadBranch + "/delete"
+		// 		ctx.Data["DeleteBranchLink"] = fmt.Sprintf("%s?commit=%s&redirect_to=%s", deleteBranchURL, pull.MergedCommitID, ctx.Data["Link"])
+		//
+		// 	}
+		issue.Comments = append(issue.Comments, &reviewComment)
+	}
+
+	// ctx.Data["IsPullBranchDeletable"] = canDelete && git.IsBranchExist(pull.HeadRepo.RepoPath(), pull.HeadBranch)
+	//
+	ctx.Data["Participants"] = participants
+	ctx.Data["NumParticipants"] = len(participants)
+	ctx.Data["SignInLink"] = setting.AppSubURL + "/user/login?redirect_to=" + ctx.Data["Link"].(string)
+	ctx.HTML(200, tplIssueView)
+}
+
+// ViewReviewCommits show commits for a pull request
+func ViewReviewCommits(ctx *context.Context) {
+	ctx.Data["PageIsPullCommits"] = true
+
+	repo, _, reviewDetails, _ := prepareReviewInfo(ctx)
+	if ctx.Written() {
+		return
+	}
+	ctx.Data["Username"] = ctx.Repo.Owner.Name
+	ctx.Data["Reponame"] = ctx.Repo.Repository.Name
+
+	reviewCommits, err := repo.ListCommitsBetween(reviewDetails.Request.TargetRef, reviewDetails.Request.ReviewRef)
+	if err != nil {
+		ctx.Handle(500, "GetReviewCommits", err)
+	}
+
+	// Reverse list
+	for i, j := 0, len(reviewCommits)-1; i < j; i, j = i+1, j-1 {
+		reviewCommits[i], reviewCommits[j] = reviewCommits[j], reviewCommits[i]
+	}
+
+	commits := list.New()
+	for _, commitHash := range reviewCommits {
+		commit, err := ctx.Repo.GitRepo.GetCommit(commitHash)
+		if err != nil {
+			ctx.Handle(500, "GetReviewCommit", err)
+		}
+		commits.PushBack(commit)
+	}
+
+	commits = models.ValidateCommitsWithEmails(commits)
+	ctx.Data["Commits"] = commits
+	ctx.Data["CommitCount"] = commits.Len()
+
+	ctx.HTML(200, tplPullCommits)
+}
+
+// ViewReviewFiles render pull request changed files list page
+func ViewReviewFiles(ctx *context.Context) {
+	ctx.Data["PageIsPullFiles"] = true
+
+	repo, _, reviewDetails, _ := prepareReviewInfo(ctx)
+
+	if ctx.Written() {
+		return
+	}
+
+	reviewCommits, err := repo.ListCommitsBetween(reviewDetails.Request.TargetRef, reviewDetails.Request.ReviewRef)
+	if err != nil {
+		ctx.Handle(500, "ListCommitsBetween", err)
+	}
+
+	startCommitID, err := reviewDetails.GetBaseCommit()
+	if err != nil {
+		ctx.Handle(500, "GetBaseCommit", err)
+	}
+
+	endCommitID := reviewCommits[len(reviewCommits)-1]
+	diff, err := models.GetDiffRange(ctx.Repo.GitRepo.Path,
+		startCommitID, endCommitID, setting.Git.MaxGitDiffLines,
+		setting.Git.MaxGitDiffLineCharacters, setting.Git.MaxGitDiffFiles)
+	if err != nil {
+		ctx.Handle(500, "GetDiffRange", err)
+		return
+	}
+	ctx.Data["Diff"] = diff
+	ctx.Data["DiffNotAvailable"] = diff.NumFiles() == 0
+
+	commit, err := ctx.Repo.GitRepo.GetCommit(endCommitID)
+	if err != nil {
+		ctx.Handle(500, "GetCommit", err)
+		return
+	}
+
+	headTarget := path.Join(ctx.Repo.Owner.Name, ctx.Repo.Repository.Name)
+	ctx.Data["Username"] = ctx.Repo.Owner.Name
+	ctx.Data["Reponame"] = ctx.Repo.Repository.Name
+	ctx.Data["IsImageFile"] = commit.IsImageFile
+	ctx.Data["SourcePath"] = setting.AppSubURL + "/" + path.Join(headTarget, "src", endCommitID)
+	ctx.Data["BeforeSourcePath"] = setting.AppSubURL + "/" + path.Join(headTarget, "src", startCommitID)
+	ctx.Data["RawPath"] = setting.AppSubURL + "/" + path.Join(headTarget, "raw", endCommitID)
+	ctx.Data["RequireHighlightJS"] = true
+
+	ctx.HTML(200, tplPullFiles)
+}
diff --git a/routers/repo/setting.go b/routers/repo/setting.go
index e29f0fcb1f3cf..ec6772ab6130e 100644
--- a/routers/repo/setting.go
+++ b/routers/repo/setting.go
@@ -152,6 +152,7 @@ func SettingsPost(ctx *context.Context, form auth.RepoSettingForm) {
 		repo.ExternalTrackerFormat = form.TrackerURLFormat
 		repo.ExternalTrackerStyle = form.TrackerIssueStyle
 		repo.EnablePulls = form.EnablePulls
+		repo.EnableReviews = form.EnableReviews
 
 		if err := models.UpdateRepository(repo, false); err != nil {
 			ctx.Handle(500, "UpdateRepository", err)
diff --git a/templates/repo/header.tmpl b/templates/repo/header.tmpl
index 9b94e799a74a6..fe2fd719e1472 100644
--- a/templates/repo/header.tmpl
+++ b/templates/repo/header.tmpl
@@ -62,6 +62,11 @@
 					<i class="octicon octicon-git-pull-request"></i> {{.i18n.Tr "repo.pulls"}} <span class="ui {{if not .Repository.NumOpenPulls}}gray{{else}}blue{{end}} small label">{{.Repository.NumOpenPulls}}</span>
 				</a>
 			{{end}}
+			{{if .Repository.AllowsReviews}}
+				<a class="{{if .PageIsReviewList}}active{{end}} item" href="{{.RepoLink}}/reviews">
+					<i class="octicon octicon-git-review-request"></i> {{.i18n.Tr "repo.reviews"}} <span class="ui {{if not .Repository.NumOpenReviews}}gray{{else}}blue{{end}} small label">{{.Repository.NumOpenReviews}}</span>
+				</a>
+			{{end}}
 			<a class="{{if (or (.PageIsCommits) (.PageIsDiff))}}active{{end}} item" href="{{.RepoLink}}/commits/{{EscapePound .BranchName}}">
 				<i class="octicon octicon-history"></i> {{.i18n.Tr "repo.commits"}} <span class="ui {{if not .CommitsCount}}gray{{else}}blue{{end}} small label">{{.CommitsCount}}</span>
 			</a>
diff --git a/templates/repo/issue/list.tmpl b/templates/repo/issue/list.tmpl
index d00c9aea21144..83fcaf30d66af 100644
--- a/templates/repo/issue/list.tmpl
+++ b/templates/repo/issue/list.tmpl
@@ -101,8 +101,16 @@
 			{{range .Issues}}
 				{{ $timeStr:= TimeSince .Created $.Lang }}
 				<li class="item">
-					<div class="ui {{if .IsRead}}black{{else}}green{{end}} label">#{{.Index}}</div>
-					<a class="title has-emoji" href="{{$.Link}}/{{.Index}}">{{.Title}}</a>
+					{{if .IsReview}}
+						<a class="title review has-emoji" href="{{$.Link}}/{{.GetIndex}}">{{.Title}}</a>
+						<br/>
+						<div class="revision">{{.GetIndex}}</div>
+					{{end}}
+
+					{{if not .IsReview}}
+						<div class="ui {{if .IsRead}}black{{else}}green{{end}} label">#{{.GetIndex}}</div>
+						<a class="title has-emoji" href="{{$.Link}}/{{.GetIndex}}">{{.Title}}</a>
+					{{end}}
 
 					{{range .Labels}}
 						<a class="ui label" href="{{$.Link}}?type={{$.ViewType}}&state={{$.State}}&labels={{.ID}}&milestone={{$.MilestoneID}}&assignee={{$.AssigneeID}}" style="color: {{.ForegroundColor}}; background-color: {{.Color}}">{{.Name}}</a>
diff --git a/templates/repo/issue/view.tmpl b/templates/repo/issue/view.tmpl
index 2260f17399d9b..e0caae2243ccb 100644
--- a/templates/repo/issue/view.tmpl
+++ b/templates/repo/issue/view.tmpl
@@ -13,7 +13,7 @@
 			</div>
 		</div>
 		<div class="ui divider"></div>
-		{{if .Issue.IsPull}}
+		{{if or .Issue.IsPull .Issue.IsReview}}
 			{{template "repo/issue/view_title" .}}
 			{{template "repo/pulls/tab_menu" .}}
 			<div class="ui bottom attached tab pull segment active" data-tab="request-{{.ID}}">
diff --git a/templates/repo/issue/view_content.tmpl b/templates/repo/issue/view_content.tmpl
index 8c1f266f1c689..1089ba3af6a40 100644
--- a/templates/repo/issue/view_content.tmpl
+++ b/templates/repo/issue/view_content.tmpl
@@ -4,7 +4,7 @@
 			{{template "base/alert" .}}
 		</div>
 	{{end}}
-	{{if not .Issue.IsPull}}
+	{{if not (or .Issue.IsPull .Issue.IsReview)}}
 		{{template "repo/issue/view_title" .}}
 	{{end}}
 
@@ -35,7 +35,7 @@
 							{{end}}
 						</div>
 						<div class="raw-content hide">{{.Issue.Content}}</div>
-						<div class="edit-content-zone hide" data-write="issue-{{.Issue.ID}}-write" data-preview="issue-{{.Issue.ID}}-preview" data-update-url="{{$.RepoLink}}/issues/{{.Issue.Index}}/content" data-context="{{.RepoLink}}"></div>
+						<div class="edit-content-zone hide" data-write="issue-{{.Issue.ID}}-write" data-preview="issue-{{.Issue.ID}}-preview" data-update-url="{{$.RepoLink}}/issues/{{.Issue.GetIndex}}/content" data-context="{{.RepoLink}}"></div>
 					</div>
 					{{if .Issue.Attachments}}
 						<div class="ui bottom attached segment">
@@ -88,6 +88,18 @@
 								</div>
 							</div>
 							<div class="ui attached segment">
+								<div class="ui attached table segment">
+									<div class="file-view code-view has-emoji">
+										<table>
+											<tbody>
+												<tr>
+													<td class="lines-num">{{.LineNums}}</td>
+													<td class="lines-code"><pre><code class="{{.HighlightClass}}"><ol class="linenums">{{.FileContent}}</ol></code></pre></td>
+												</tr>
+											</tbody>
+										</table>
+									</div>
+								</div>
 								<div class="render-content markdown has-emoji">
 									{{if .RenderedContent}}
 										{{.RenderedContent|Str2html}}
@@ -220,7 +232,7 @@
 						<img src="{{.SignedUser.RelAvatarLink}}">
 					</a>
 					<div class="content">
-						<form class="ui segment form" id="comment-form" action="{{$.RepoLink}}/issues/{{.Issue.Index}}/comments" method="post">
+						<form class="ui segment form" id="comment-form" action="{{$.RepoLink}}/issues/{{.Issue.GetIndex}}/comments" method="post">
 							{{template "repo/issue/comment_tab" .}}
 							{{.CsrfTokenHtml}}
 							<input id="status" name="status" type="hidden">
@@ -258,7 +270,7 @@
 					<strong>{{.i18n.Tr "repo.issues.new.labels"}}</strong>
 					<span class="octicon octicon-gear"></span>
 				</span>
-				<div class="filter menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.Index}}/label">
+				<div class="filter menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.GetIndex}}/label">
 					<div class="no-select item">{{.i18n.Tr "repo.issues.new.clear_labels"}}</div>
 					{{range .Labels}}
 						<a class="{{if .IsChecked}}checked{{end}} item" href="#" data-id="{{.ID}}" data-id-selector="#label_{{.ID}}"><span class="octicon {{if .IsChecked}}octicon-check{{end}}"></span><span class="label color" style="background-color: {{.Color}}"></span> {{.Name}}</a>
@@ -282,7 +294,7 @@
 					<strong>{{.i18n.Tr "repo.issues.new.milestone"}}</strong>
 					<span class="octicon octicon-gear"></span>
 				</span>
-				<div class="menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.Index}}/milestone">
+				<div class="menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.GetIndex}}/milestone">
 					<div class="no-select item">{{.i18n.Tr "repo.issues.new.clear_milestone"}}</div>
 					{{if .OpenMilestones}}
 						<div class="divider"></div>
@@ -323,7 +335,7 @@
 					<strong>{{.i18n.Tr "repo.issues.new.assignee"}}</strong>
 					<span class="octicon octicon-gear"></span>
 				</span>
-				<div class="menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.Index}}/assignee">
+				<div class="menu" data-action="update" data-update-url="{{$.RepoLink}}/issues/{{$.Issue.GetIndex}}/assignee">
 					<div class="no-select item">{{.i18n.Tr "repo.issues.new.clear_assignee"}}</div>
 					{{range .Assignees}}
 						<div class="item" data-id="{{.ID}}" data-href="{{$.RepoLink}}/issues?assignee={{.ID}}" data-avatar="{{.RelAvatarLink}}"><img src="{{.RelAvatarLink}}"> {{.Name}}</div>
@@ -389,4 +401,4 @@
 		{{.i18n.Tr "repo.branch.delete_notices_2" .HeadTarget | Safe}}<br>
 	</div>
 	{{template "base/delete_modal_actions" .}}
-</div>
\ No newline at end of file
+</div>
diff --git a/templates/repo/issue/view_title.tmpl b/templates/repo/issue/view_title.tmpl
index 3f3b62e6534a3..bcb7e05416f8e 100644
--- a/templates/repo/issue/view_title.tmpl
+++ b/templates/repo/issue/view_title.tmpl
@@ -1,7 +1,12 @@
 <div class="sixteen wide column title">
 	<div class="ui grid">
 		<h1 class="twelve wide column">
-			<span class="index">#{{.Issue.Index}}</span> <span id="issue-title" class="has-emoji">{{.Issue.Title}}</span>
+			{{if .Issue.IsReview}}
+				<span id="issue-title" class="has-emoji">{{.Issue.Title}}</span>
+			{{end}}
+			{{if not .Issue.IsReview}}
+				<span class="index">#{{.Issue.GetIndex}}</span> <span id="issue-title" class="has-emoji">{{.Issue.Title}}</span>
+			{{end}}
 			<div id="edit-title-input" class="ui input" style="display: none">
 				<input value="{{.Issue.Title}}">
 			</div>
@@ -15,6 +20,9 @@
 				</div>
 			</div>
 		{{end}}
+		{{if .Issue.IsReview}}
+			<div class="twelve wide column revision">{{.Issue.GetIndex}}</div>
+		{{end}}
 	</div>
 	{{if .HasMerged}}
 		<div class="ui purple large label"><i class="octicon octicon-git-pull-request"></i> {{.i18n.Tr "repo.pulls.merged"}}</div>
@@ -24,7 +32,7 @@
 		<div class="ui green large label"><i class="octicon octicon-issue-opened"></i> {{.i18n.Tr "repo.issues.open_title"}}</div>
 	{{end}}
 
-	{{if .Issue.IsPull}}
+	{{if or .Issue.IsPull .Issue.IsReview}}
 		{{if .Issue.PullRequest.HasMerged}}
 			{{ $mergedStr:= TimeSince .Issue.PullRequest.Merged $.Lang }}
 			<a {{if gt .Issue.PullRequest.Merger.ID 0}}href="{{.Issue.PullRequest.Merger.HomeLink}}"{{end}}>{{.Issue.PullRequest.Merger.Name}}</a>
diff --git a/templates/repo/pulls/tab_menu.tmpl b/templates/repo/pulls/tab_menu.tmpl
index c81eab0dfed3e..a345cf50b0c6f 100644
--- a/templates/repo/pulls/tab_menu.tmpl
+++ b/templates/repo/pulls/tab_menu.tmpl
@@ -1,15 +1,15 @@
 <div class="ui top attached pull tabular menu">
-	<a class="item {{if .PageIsPullConversation}}active{{end}}" href="{{.RepoLink}}/pulls/{{.Issue.Index}}">
+	<a class="item {{if .PageIsPullConversation}}active{{end}}" href="{{.RepoLink}}/{{if .Issue.IsReview}}reviews{{end}}{{if not .Issue.IsReview}}pulls{{end}}/{{.Issue.GetIndex}}">
 		<span class="octicon octicon-comment-discussion"></span>
 		{{$.i18n.Tr "repo.pulls.tab_conversation"}}
 		<span class="ui {{if not .Issue.NumComments}}gray{{else}}blue{{end}} small label">{{.Issue.NumComments}}</span>
 	</a>
-	<a class="item {{if .PageIsPullCommits}}active{{end}}" {{if .NumCommits}}href="{{.RepoLink}}/pulls/{{.Issue.Index}}/commits"{{end}}>
+	<a class="item {{if .PageIsPullCommits}}active{{end}}" {{if .NumCommits}}href="{{.RepoLink}}/{{if .Issue.IsReview}}reviews{{end}}{{if not .Issue.IsReview}}pulls{{end}}/{{.Issue.GetIndex}}/commits"{{end}}>
 		<span class="octicon octicon-git-commit"></span>
 		{{$.i18n.Tr "repo.pulls.tab_commits"}}
 		<span class="ui {{if not .NumCommits}}gray{{else}}blue{{end}} small label">{{if .NumCommits}}{{.NumCommits}}{{else}}N/A{{end}}</span>
 	</a>
-	<a class="item {{if .PageIsPullFiles}}active{{end}}" {{if .NumFiles}}href="{{.RepoLink}}/pulls/{{.Issue.Index}}/files"{{end}}>
+	<a class="item {{if .PageIsPullFiles}}active{{end}}" {{if .NumFiles}}href="{{.RepoLink}}/{{if .Issue.IsReview}}reviews{{end}}{{if not .Issue.IsReview}}pulls{{end}}/{{.Issue.GetIndex}}/files"{{end}}>
 		<span class="octicon octicon-diff"></span>
 		{{$.i18n.Tr "repo.pulls.tab_files"}}
 		<span class="ui {{if not .NumFiles}}gray{{else}}blue{{end}} small label">{{if .NumFiles}}{{.NumFiles}}{{else}}N/A{{end}}</span>
diff --git a/templates/repo/settings/options.tmpl b/templates/repo/settings/options.tmpl
index 2588966c9dcfd..6abd0e1e0368d 100644
--- a/templates/repo/settings/options.tmpl
+++ b/templates/repo/settings/options.tmpl
@@ -201,6 +201,16 @@
 							</div>
 						{{end}}
 
+						<div class="ui divider"></div>
+
+						<div class="inline field">
+							<label>{{.i18n.Tr "repo.reviews"}}</label>
+							<div class="ui checkbox">
+								<input name="enable_reviews" type="checkbox" {{if .Repository.EnableReviews}}checked{{end}}>
+								<label>{{.i18n.Tr "repo.settings.reviews_desc"}}</label>
+							</div>
+						</div>
+
 						<div class="ui divider"></div>
 						<div class="field">
 							<button class="ui green button">{{$.i18n.Tr "repo.settings.update_settings"}}</button>
diff --git a/vendor/github.com/google/git-appraise/LICENSE b/vendor/github.com/google/git-appraise/LICENSE
new file mode 100644
index 0000000000000..d645695673349
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/LICENSE
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
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+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
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+      including but not limited to software source code, documentation
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+
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+
+      "Work" shall mean the work of authorship, whether in Source or
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+      "Contribution" shall mean any work of authorship, including
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+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
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+
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+
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+
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+
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+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
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+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
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+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+   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 or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/vendor/github.com/google/git-appraise/repository/git.go b/vendor/github.com/google/git-appraise/repository/git.go
new file mode 100644
index 0000000000000..816cbfa98793f
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/repository/git.go
@@ -0,0 +1,834 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package repository contains helper methods for working with the Git repo.
+package repository
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/sha1"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+const branchRefPrefix = "refs/heads/"
+
+// GitRepo represents an instance of a (local) git repository.
+type GitRepo struct {
+	Path string
+}
+
+// Run the given git command with the given I/O reader/writers, returning an error if it fails.
+func (repo *GitRepo) runGitCommandWithIO(stdin io.Reader, stdout, stderr io.Writer, args ...string) error {
+	cmd := exec.Command("git", args...)
+	log.Print("runGitCommandWithIO", repo, args)
+	cmd.Dir = repo.Path
+	cmd.Stdin = stdin
+	cmd.Stdout = stdout
+	cmd.Stderr = stderr
+	return cmd.Run()
+}
+
+// Run the given git command and return its stdout, or an error if the command fails.
+func (repo *GitRepo) runGitCommandRaw(args ...string) (string, string, error) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	err := repo.runGitCommandWithIO(nil, &stdout, &stderr, args...)
+	return strings.TrimSpace(stdout.String()), strings.TrimSpace(stderr.String()), err
+}
+
+// Run the given git command and return its stdout, or an error if the command fails.
+func (repo *GitRepo) runGitCommand(args ...string) (string, error) {
+	stdout, stderr, err := repo.runGitCommandRaw(args...)
+	if err != nil {
+		if stderr == "" {
+			stderr = "Error running git command: " + strings.Join(args, " ")
+		}
+		err = fmt.Errorf(stderr)
+	}
+	return stdout, err
+}
+
+// Run the given git command using the same stdin, stdout, and stderr as the review tool.
+func (repo *GitRepo) runGitCommandInline(args ...string) error {
+	return repo.runGitCommandWithIO(os.Stdin, os.Stdout, os.Stderr, args...)
+}
+
+// NewGitRepo determines if the given working directory is inside of a git repository,
+// and returns the corresponding GitRepo instance if it is.
+func NewGitRepo(path string) (*GitRepo, error) {
+	repo := &GitRepo{Path: path}
+	log.Print("NewGitRepo", repo)
+	_, _, err := repo.runGitCommandRaw("rev-parse")
+	log.Print("NewGitRepo after init", repo)
+	log.Print("NewGitRepo after init", err)
+	if err == nil {
+		log.Print("NewGitRepo return", repo)
+		return repo, nil
+	}
+	if _, ok := err.(*exec.ExitError); ok {
+		return nil, err
+	}
+	return nil, err
+}
+
+// GetPath returns the path to the repo.
+func (repo *GitRepo) GetPath() string {
+	return repo.Path
+}
+
+// GetRepoStateHash returns a hash which embodies the entire current state of a repository.
+func (repo *GitRepo) GetRepoStateHash() (string, error) {
+	stateSummary, error := repo.runGitCommand("show-ref")
+	return fmt.Sprintf("%x", sha1.Sum([]byte(stateSummary))), error
+}
+
+// GetUserEmail returns the email address that the user has used to configure git.
+func (repo *GitRepo) GetUserEmail() (string, error) {
+	return repo.runGitCommand("config", "user.email")
+}
+
+// GetCoreEditor returns the name of the editor that the user has used to configure git.
+func (repo *GitRepo) GetCoreEditor() (string, error) {
+	return repo.runGitCommand("var", "GIT_EDITOR")
+}
+
+// GetSubmitStrategy returns the way in which a review is submitted
+func (repo *GitRepo) GetSubmitStrategy() (string, error) {
+	submitStrategy, _ := repo.runGitCommand("config", "appraise.submit")
+	return submitStrategy, nil
+}
+
+// HasUncommittedChanges returns true if there are local, uncommitted changes.
+func (repo *GitRepo) HasUncommittedChanges() (bool, error) {
+	out, err := repo.runGitCommand("status", "--porcelain")
+	if err != nil {
+		return false, err
+	}
+	if len(out) > 0 {
+		return true, nil
+	}
+	return false, nil
+}
+
+// VerifyCommit verifies that the supplied hash points to a known commit.
+func (repo *GitRepo) VerifyCommit(hash string) error {
+	out, err := repo.runGitCommand("cat-file", "-t", hash)
+	if err != nil {
+		return err
+	}
+	objectType := strings.TrimSpace(string(out))
+	if objectType != "commit" {
+		return fmt.Errorf("Hash %q points to a non-commit object of type %q", hash, objectType)
+	}
+	return nil
+}
+
+// VerifyGitRef verifies that the supplied ref points to a known commit.
+func (repo *GitRepo) VerifyGitRef(ref string) error {
+	_, err := repo.runGitCommand("show-ref", "--verify", ref)
+	return err
+}
+
+// GetHeadRef returns the ref that is the current HEAD.
+func (repo *GitRepo) GetHeadRef() (string, error) {
+	return repo.runGitCommand("symbolic-ref", "HEAD")
+}
+
+// GetCommitHash returns the hash of the commit pointed to by the given ref.
+func (repo *GitRepo) GetCommitHash(ref string) (string, error) {
+	return repo.runGitCommand("show", "-s", "--format=%H", ref)
+}
+
+// ResolveRefCommit returns the commit pointed to by the given ref, which may be a remote ref.
+//
+// This differs from GetCommitHash which only works on exact matches, in that it will try to
+// intelligently handle the scenario of a ref not existing locally, but being known to exist
+// in a remote repo.
+//
+// This method should be used when a command may be performed by either the reviewer or the
+// reviewee, while GetCommitHash should be used when the encompassing command should only be
+// performed by the reviewee.
+func (repo *GitRepo) ResolveRefCommit(ref string) (string, error) {
+	if err := repo.VerifyGitRef(ref); err == nil {
+		return repo.GetCommitHash(ref)
+	}
+	if strings.HasPrefix(ref, "refs/heads/") {
+		// The ref is a branch. Check if it exists in exactly one remote
+		pattern := strings.Replace(ref, "refs/heads", "**", 1)
+		matchingOutput, err := repo.runGitCommand("for-each-ref", "--format=%(refname)", pattern)
+		if err != nil {
+			return "", err
+		}
+		matchingRefs := strings.Split(matchingOutput, "\n")
+		if len(matchingRefs) == 1 && matchingRefs[0] != "" {
+			// There is exactly one match
+			return repo.GetCommitHash(matchingRefs[0])
+		}
+		return "", fmt.Errorf("Unable to find a git ref matching the pattern %q", pattern)
+	}
+	return "", fmt.Errorf("Unknown git ref %q", ref)
+}
+
+// GetCommitMessage returns the message stored in the commit pointed to by the given ref.
+func (repo *GitRepo) GetCommitMessage(ref string) (string, error) {
+	return repo.runGitCommand("show", "-s", "--format=%B", ref)
+}
+
+// GetCommitTime returns the commit time of the commit pointed to by the given ref.
+func (repo *GitRepo) GetCommitTime(ref string) (string, error) {
+	return repo.runGitCommand("show", "-s", "--format=%ct", ref)
+}
+
+// GetLastParent returns the last parent of the given commit (as ordered by git).
+func (repo *GitRepo) GetLastParent(ref string) (string, error) {
+	return repo.runGitCommand("rev-list", "--skip", "1", "-n", "1", ref)
+}
+
+// GetCommitDetails returns the details of a commit's metadata.
+func (repo GitRepo) GetCommitDetails(ref string) (*CommitDetails, error) {
+	var err error
+	show := func(formatString string) (result string) {
+		if err != nil {
+			return ""
+		}
+		result, err = repo.runGitCommand("show", "-s", ref, fmt.Sprintf("--format=tformat:%s", formatString))
+		return result
+	}
+
+	jsonFormatString := "{\"tree\":\"%T\", \"time\": \"%at\"}"
+	detailsJSON := show(jsonFormatString)
+	if err != nil {
+		return nil, err
+	}
+	var details CommitDetails
+	err = json.Unmarshal([]byte(detailsJSON), &details)
+	if err != nil {
+		return nil, err
+	}
+	details.Author = show("%an")
+	details.AuthorEmail = show("%ae")
+	details.Summary = show("%s")
+	parentsString := show("%P")
+	details.Parents = strings.Split(parentsString, " ")
+	if err != nil {
+		return nil, err
+	}
+	return &details, nil
+}
+
+// MergeBase determines if the first commit that is an ancestor of the two arguments.
+func (repo *GitRepo) MergeBase(a, b string) (string, error) {
+	return repo.runGitCommand("merge-base", a, b)
+}
+
+// IsAncestor determines if the first argument points to a commit that is an ancestor of the second.
+func (repo *GitRepo) IsAncestor(ancestor, descendant string) (bool, error) {
+	_, _, err := repo.runGitCommandRaw("merge-base", "--is-ancestor", ancestor, descendant)
+	if err == nil {
+		return true, nil
+	}
+	if _, ok := err.(*exec.ExitError); ok {
+		return false, nil
+	}
+	return false, fmt.Errorf("Error while trying to determine commit ancestry: %v", err)
+}
+
+// Diff computes the diff between two given commits.
+func (repo *GitRepo) Diff(left, right string, diffArgs ...string) (string, error) {
+	args := []string{"diff"}
+	args = append(args, diffArgs...)
+	args = append(args, fmt.Sprintf("%s..%s", left, right))
+	return repo.runGitCommand(args...)
+}
+
+// Show returns the contents of the given file at the given commit.
+func (repo *GitRepo) Show(commit, path string) (string, error) {
+	return repo.runGitCommand("show", fmt.Sprintf("%s:%s", commit, path))
+}
+
+// SwitchToRef changes the currently-checked-out ref.
+func (repo *GitRepo) SwitchToRef(ref string) error {
+	// If the ref starts with "refs/heads/", then we have to trim that prefix,
+	// or else we will wind up in a detached HEAD state.
+	if strings.HasPrefix(ref, branchRefPrefix) {
+		ref = ref[len(branchRefPrefix):]
+	}
+	_, err := repo.runGitCommand("checkout", ref)
+	return err
+}
+
+// mergeArchives merges two archive refs.
+func (repo *GitRepo) mergeArchives(archive, remoteArchive string) error {
+	remoteHash, err := repo.GetCommitHash(remoteArchive)
+	if err != nil {
+		return err
+	}
+	if remoteHash == "" {
+		// The remote archive does not exist, so we have nothing to do
+		return nil
+	}
+
+	archiveHash, err := repo.GetCommitHash(archive)
+	if err != nil {
+		return err
+	}
+	if archiveHash == "" {
+		// The local archive does not exist, so we merely need to set it
+		_, err := repo.runGitCommand("update-ref", archive, remoteHash)
+		return err
+	}
+
+	isAncestor, err := repo.IsAncestor(archiveHash, remoteHash)
+	if err != nil {
+		return err
+	}
+	if isAncestor {
+		// The archive can simply be fast-forwarded
+		_, err := repo.runGitCommand("update-ref", archive, remoteHash, archiveHash)
+		return err
+	}
+
+	// Create a merge commit of the two archives
+	refDetails, err := repo.GetCommitDetails(remoteArchive)
+	if err != nil {
+		return err
+	}
+	newArchiveHash, err := repo.runGitCommand("commit-tree", "-p", remoteHash, "-p", archiveHash, "-m", "Merge local and remote archives", refDetails.Tree)
+	if err != nil {
+		return err
+	}
+	newArchiveHash = strings.TrimSpace(newArchiveHash)
+	_, err = repo.runGitCommand("update-ref", archive, newArchiveHash, archiveHash)
+	return err
+}
+
+// ArchiveRef adds the current commit pointed to by the 'ref' argument
+// under the ref specified in the 'archive' argument.
+//
+// Both the 'ref' and 'archive' arguments are expected to be the fully
+// qualified names of git refs (e.g. 'refs/heads/my-change' or
+// 'refs/devtools/archives/reviews').
+//
+// If the ref pointed to by the 'archive' argument does not exist
+// yet, then it will be created.
+func (repo *GitRepo) ArchiveRef(ref, archive string) error {
+	refHash, err := repo.GetCommitHash(ref)
+	if err != nil {
+		return err
+	}
+	refDetails, err := repo.GetCommitDetails(ref)
+	if err != nil {
+		return err
+	}
+
+	commitTreeArgs := []string{"commit-tree"}
+	archiveHash, err := repo.GetCommitHash(archive)
+	if err != nil {
+		archiveHash = ""
+	} else {
+		commitTreeArgs = append(commitTreeArgs, "-p", archiveHash)
+	}
+	commitTreeArgs = append(commitTreeArgs, "-p", refHash, "-m", fmt.Sprintf("Archive %s", refHash), refDetails.Tree)
+	newArchiveHash, err := repo.runGitCommand(commitTreeArgs...)
+	if err != nil {
+		return err
+	}
+	newArchiveHash = strings.TrimSpace(newArchiveHash)
+	updateRefArgs := []string{"update-ref", archive, newArchiveHash}
+	if archiveHash != "" {
+		updateRefArgs = append(updateRefArgs, archiveHash)
+	}
+	_, err = repo.runGitCommand(updateRefArgs...)
+	return err
+}
+
+// MergeRef merges the given ref into the current one.
+//
+// The ref argument is the ref to merge, and fastForward indicates that the
+// current ref should only move forward, as opposed to creating a bubble merge.
+// The messages argument(s) provide text that should be included in the default
+// merge commit message (separated by blank lines).
+func (repo *GitRepo) MergeRef(ref string, fastForward bool, messages ...string) error {
+	args := []string{"merge"}
+	if fastForward {
+		args = append(args, "--ff", "--ff-only")
+	} else {
+		args = append(args, "--no-ff")
+	}
+	if len(messages) > 0 {
+		commitMessage := strings.Join(messages, "\n\n")
+		args = append(args, "-e", "-m", commitMessage)
+	}
+	args = append(args, ref)
+	return repo.runGitCommandInline(args...)
+}
+
+// RebaseRef rebases the current ref onto the given one.
+func (repo *GitRepo) RebaseRef(ref string) error {
+	return repo.runGitCommandInline("rebase", "-i", ref)
+}
+
+// ListCommits returns the list of commits reachable from the given ref.
+//
+// The generated list is in chronological order (with the oldest commit first).
+//
+// If the specified ref does not exist, then this method returns an empty result.
+func (repo *GitRepo) ListCommits(ref string) []string {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	if err := repo.runGitCommandWithIO(nil, &stdout, &stderr, "rev-list", "--reverse", ref); err != nil {
+		return nil
+	}
+
+	byteLines := bytes.Split(stdout.Bytes(), []byte("\n"))
+	var commits []string
+	for _, byteLine := range byteLines {
+		commits = append(commits, string(byteLine))
+	}
+	return commits
+}
+
+// ListCommitsBetween returns the list of commits between the two given revisions.
+//
+// The "from" parameter is the starting point (exclusive), and the "to"
+// parameter is the ending point (inclusive).
+//
+// The "from" commit does not need to be an ancestor of the "to" commit. If it
+// is not, then the merge base of the two is used as the starting point.
+// Admittedly, this makes calling these the "between" commits is a bit of a
+// misnomer, but it also makes the method easier to use when you want to
+// generate the list of changes in a feature branch, as it eliminates the need
+// to explicitly calculate the merge base. This also makes the semantics of the
+// method compatible with git's built-in "rev-list" command.
+//
+// The generated list is in chronological order (with the oldest commit first).
+func (repo *GitRepo) ListCommitsBetween(from, to string) ([]string, error) {
+	out, err := repo.runGitCommand("rev-list", "--reverse", from+".."+to)
+	if err != nil {
+		return nil, err
+	}
+	if out == "" {
+		return nil, nil
+	}
+	return strings.Split(out, "\n"), nil
+}
+
+// GetNotes uses the "git" command-line tool to read the notes from the given ref for a given revision.
+func (repo *GitRepo) GetNotes(notesRef, revision string) []Note {
+	var notes []Note
+	rawNotes, err := repo.runGitCommand("notes", "--ref", notesRef, "show", revision)
+	if err != nil {
+		// We just assume that this means there are no notes
+		return nil
+	}
+	for _, line := range strings.Split(rawNotes, "\n") {
+		notes = append(notes, Note([]byte(line)))
+	}
+	return notes
+}
+
+func stringsReader(s []*string) io.Reader {
+	var subReaders []io.Reader
+	for _, strPtr := range s {
+		subReader := strings.NewReader(*strPtr)
+		subReaders = append(subReaders, subReader, strings.NewReader("\n"))
+	}
+	return io.MultiReader(subReaders...)
+}
+
+// splitBatchCheckOutput parses the output of a 'git cat-file --batch-check=...' command.
+//
+// The output is expected to be formatted as a series of entries, with each
+// entry consisting of:
+// 1. The SHA1 hash of the git object being output, followed by a space.
+// 2. The git "type" of the object (commit, blob, tree, missing, etc), followed by a newline.
+//
+// To generate this format, make sure that the 'git cat-file' command includes
+// the argument '--batch-check=%(objectname) %(objecttype)'.
+//
+// The return value is a map from object hash to a boolean indicating if that object is a commit.
+func splitBatchCheckOutput(out *bytes.Buffer) (map[string]bool, error) {
+	isCommit := make(map[string]bool)
+	reader := bufio.NewReader(out)
+	for {
+		nameLine, err := reader.ReadString(byte(' '))
+		if err == io.EOF {
+			return isCommit, nil
+		}
+		if err != nil {
+			return nil, fmt.Errorf("Failure while reading the next object name: %v", err)
+		}
+		nameLine = strings.TrimSuffix(nameLine, " ")
+		typeLine, err := reader.ReadString(byte('\n'))
+		if err != nil && err != io.EOF {
+			return nil, fmt.Errorf("Failure while reading the next object type: %q - %v", nameLine, err)
+		}
+		typeLine = strings.TrimSuffix(typeLine, "\n")
+		if typeLine == "commit" {
+			isCommit[nameLine] = true
+		}
+	}
+}
+
+// splitBatchCatFileOutput parses the output of a 'git cat-file --batch=...' command.
+//
+// The output is expected to be formatted as a series of entries, with each
+// entry consisting of:
+// 1. The SHA1 hash of the git object being output, followed by a newline.
+// 2. The size of the object's contents in bytes, followed by a newline.
+// 3. The objects contents.
+//
+// To generate this format, make sure that the 'git cat-file' command includes
+// the argument '--batch=%(objectname)\n%(objectsize)'.
+func splitBatchCatFileOutput(out *bytes.Buffer) (map[string][]byte, error) {
+	contentsMap := make(map[string][]byte)
+	reader := bufio.NewReader(out)
+	for {
+		nameLine, err := reader.ReadString(byte('\n'))
+		if strings.HasSuffix(nameLine, "\n") {
+			nameLine = strings.TrimSuffix(nameLine, "\n")
+		}
+		if err == io.EOF {
+			return contentsMap, nil
+		}
+		if err != nil {
+			return nil, fmt.Errorf("Failure while reading the next object name: %v", err)
+		}
+		sizeLine, err := reader.ReadString(byte('\n'))
+		if strings.HasSuffix(sizeLine, "\n") {
+			sizeLine = strings.TrimSuffix(sizeLine, "\n")
+		}
+		if err != nil {
+			return nil, fmt.Errorf("Failure while reading the next object size: %q - %v", nameLine, err)
+		}
+		size, err := strconv.Atoi(sizeLine)
+		if err != nil {
+			return nil, fmt.Errorf("Failure while parsing the next object size: %q - %v", nameLine, err)
+		}
+		contentBytes := make([]byte, size, size)
+		readDest := contentBytes
+		len := 0
+		err = nil
+		for err == nil && len < size {
+			nextLen := 0
+			nextLen, err = reader.Read(readDest)
+			len += nextLen
+			readDest = contentBytes[len:]
+		}
+		contentsMap[nameLine] = contentBytes
+		if err == io.EOF {
+			return contentsMap, nil
+		}
+		if err != nil {
+			return nil, err
+		}
+		for bs, err := reader.Peek(1); err == nil && bs[0] == byte('\n'); bs, err = reader.Peek(1) {
+			reader.ReadByte()
+		}
+	}
+}
+
+// notesMapping represents the association between a git object and the notes for that object.
+type notesMapping struct {
+	ObjectHash *string
+	NotesHash  *string
+}
+
+// notesOverview represents a high-level overview of all the notes under a single notes ref.
+type notesOverview struct {
+	NotesMappings      []*notesMapping
+	ObjectHashesReader io.Reader
+	NotesHashesReader  io.Reader
+}
+
+// notesOverview returns an overview of the git notes stored under the given ref.
+func (repo *GitRepo) notesOverview(notesRef string) (*notesOverview, error) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	if err := repo.runGitCommandWithIO(nil, &stdout, &stderr, "notes", "--ref", notesRef, "list"); err != nil {
+		return nil, err
+	}
+
+	var notesMappings []*notesMapping
+	var objHashes []*string
+	var notesHashes []*string
+	outScanner := bufio.NewScanner(&stdout)
+	for outScanner.Scan() {
+		line := outScanner.Text()
+		lineParts := strings.Split(line, " ")
+		if len(lineParts) != 2 {
+			return nil, fmt.Errorf("Malformed output line from 'git-notes list': %q", line)
+		}
+		objHash := &lineParts[1]
+		notesHash := &lineParts[0]
+		notesMappings = append(notesMappings, &notesMapping{
+			ObjectHash: objHash,
+			NotesHash:  notesHash,
+		})
+		objHashes = append(objHashes, objHash)
+		notesHashes = append(notesHashes, notesHash)
+	}
+	err := outScanner.Err()
+	if err != nil && err != io.EOF {
+		return nil, fmt.Errorf("Failure parsing the output of 'git-notes list': %v", err)
+	}
+	return &notesOverview{
+		NotesMappings:      notesMappings,
+		ObjectHashesReader: stringsReader(objHashes),
+		NotesHashesReader:  stringsReader(notesHashes),
+	}, nil
+}
+
+// getIsCommitMap returns a mapping of all the annotated objects that are commits.
+func (overview *notesOverview) getIsCommitMap(repo *GitRepo) (map[string]bool, error) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	if err := repo.runGitCommandWithIO(overview.ObjectHashesReader, &stdout, &stderr, "cat-file", "--batch-check=%(objectname) %(objecttype)"); err != nil {
+		return nil, fmt.Errorf("Failure performing a batch file check: %v", err)
+	}
+	isCommit, err := splitBatchCheckOutput(&stdout)
+	if err != nil {
+		return nil, fmt.Errorf("Failure parsing the output of a batch file check: %v", err)
+	}
+	return isCommit, nil
+}
+
+// getNoteContentsMap returns a mapping from all the notes hashes to their contents.
+func (overview *notesOverview) getNoteContentsMap(repo *GitRepo) (map[string][]byte, error) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	if err := repo.runGitCommandWithIO(overview.NotesHashesReader, &stdout, &stderr, "cat-file", "--batch=%(objectname)\n%(objectsize)"); err != nil {
+		return nil, fmt.Errorf("Failure performing a batch file read: %v", err)
+	}
+	noteContentsMap, err := splitBatchCatFileOutput(&stdout)
+	if err != nil {
+		return nil, fmt.Errorf("Failure parsing the output of a batch file read: %v", err)
+	}
+	return noteContentsMap, nil
+}
+
+// GetAllNotes reads the contents of the notes under the given ref for every commit.
+//
+// The returned value is a mapping from commit hash to the list of notes for that commit.
+//
+// This is the batch version of the corresponding GetNotes(...) method.
+func (repo *GitRepo) GetAllNotes(notesRef string) (map[string][]Note, error) {
+	// This code is unfortunately quite complicated, but it needs to be so.
+	//
+	// Conceptually, this is equivalent to:
+	//   result := make(map[string][]Note)
+	//   for _, commit := range repo.ListNotedRevisions(notesRef) {
+	//     result[commit] = repo.GetNotes(notesRef, commit)
+	//   }
+	//   return result, nil
+	//
+	// However, that logic would require separate executions of the 'git'
+	// command for every annotated commit. For a repo with 10s of thousands
+	// of reviews, that would mean calling Cmd.Run(...) 10s of thousands of
+	// times. That, in turn, would take so long that the tool would be unusable.
+	//
+	// This method avoids that by taking advantage of the 'git cat-file --batch="..."'
+	// command. That allows us to use a single invocation of Cmd.Run(...) to
+	// inspect multiple git objects at once.
+	//
+	// As such, regardless of the number of reviews in a repo, we can get all
+	// of the notes using a total of three invocations of Cmd.Run(...):
+	//  1. One to list all the annotated objects (and their notes hash)
+	//  2. A second one to filter out all of the annotated objects that are not commits.
+	//  3. A final one to get the contents of all of the notes blobs.
+	overview, err := repo.notesOverview(notesRef)
+	if err != nil {
+		return nil, err
+	}
+	isCommit, err := overview.getIsCommitMap(repo)
+	if err != nil {
+		return nil, fmt.Errorf("Failure building the set of commit objects: %v", err)
+	}
+	noteContentsMap, err := overview.getNoteContentsMap(repo)
+	if err != nil {
+		return nil, fmt.Errorf("Failure building the mapping from notes hash to contents: %v", err)
+	}
+	commitNotesMap := make(map[string][]Note)
+	for _, notesMapping := range overview.NotesMappings {
+		if !isCommit[*notesMapping.ObjectHash] {
+			continue
+		}
+		noteBytes := noteContentsMap[*notesMapping.NotesHash]
+		byteSlices := bytes.Split(noteBytes, []byte("\n"))
+		var notes []Note
+		for _, slice := range byteSlices {
+			notes = append(notes, Note(slice))
+		}
+		commitNotesMap[*notesMapping.ObjectHash] = notes
+	}
+
+	return commitNotesMap, nil
+}
+
+// AppendNote appends a note to a revision under the given ref.
+func (repo *GitRepo) AppendNote(notesRef, revision string, note Note) error {
+	_, err := repo.runGitCommand("notes", "--ref", notesRef, "append", "-m", string(note), revision)
+	return err
+}
+
+// ListNotedRevisions returns the collection of revisions that are annotated by notes in the given ref.
+func (repo *GitRepo) ListNotedRevisions(notesRef string) []string {
+	var revisions []string
+	notesListOut, err := repo.runGitCommand("notes", "--ref", notesRef, "list")
+	if err != nil {
+		return nil
+	}
+	notesList := strings.Split(notesListOut, "\n")
+	for _, notePair := range notesList {
+		noteParts := strings.SplitN(notePair, " ", 2)
+		if len(noteParts) == 2 {
+			objHash := noteParts[1]
+			objType, err := repo.runGitCommand("cat-file", "-t", objHash)
+			// If a note points to an object that we do not know about (yet), then err will not
+			// be nil. We can safely just ignore those notes.
+			if err == nil && objType == "commit" {
+				revisions = append(revisions, objHash)
+			}
+		}
+	}
+	return revisions
+}
+
+// PushNotes pushes git notes to a remote repo.
+func (repo *GitRepo) PushNotes(remote, notesRefPattern string) error {
+	refspec := fmt.Sprintf("%s:%s", notesRefPattern, notesRefPattern)
+
+	// The push is liable to fail if the user forgot to do a pull first, so
+	// we treat errors as user errors rather than fatal errors.
+	err := repo.runGitCommandInline("push", remote, refspec)
+	if err != nil {
+		return fmt.Errorf("Failed to push to the remote '%s': %v", remote, err)
+	}
+	return nil
+}
+
+// PushNotesAndArchive pushes the given notes and archive refs to a remote repo.
+func (repo *GitRepo) PushNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	notesRefspec := fmt.Sprintf("%s:%s", notesRefPattern, notesRefPattern)
+	archiveRefspec := fmt.Sprintf("%s:%s", archiveRefPattern, archiveRefPattern)
+	err := repo.runGitCommandInline("push", remote, notesRefspec, archiveRefspec)
+	if err != nil {
+		return fmt.Errorf("Failed to push the local archive to the remote '%s': %v", remote, err)
+	}
+	return nil
+}
+
+func getRemoteNotesRef(remote, localNotesRef string) string {
+	relativeNotesRef := strings.TrimPrefix(localNotesRef, "refs/notes/")
+	return "refs/notes/" + remote + "/" + relativeNotesRef
+}
+
+func (repo *GitRepo) mergeRemoteNotes(remote, notesRefPattern string) error {
+	remoteRefs, err := repo.runGitCommand("ls-remote", remote, notesRefPattern)
+	if err != nil {
+		return err
+	}
+	for _, line := range strings.Split(remoteRefs, "\n") {
+		lineParts := strings.Split(line, "\t")
+		if len(lineParts) == 2 {
+			ref := lineParts[1]
+			remoteRef := getRemoteNotesRef(remote, ref)
+			_, err := repo.runGitCommand("notes", "--ref", ref, "merge", remoteRef, "-s", "cat_sort_uniq")
+			if err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// PullNotes fetches the contents of the given notes ref from a remote repo,
+// and then merges them with the corresponding local notes using the
+// "cat_sort_uniq" strategy.
+func (repo *GitRepo) PullNotes(remote, notesRefPattern string) error {
+	remoteNotesRefPattern := getRemoteNotesRef(remote, notesRefPattern)
+	fetchRefSpec := fmt.Sprintf("+%s:%s", notesRefPattern, remoteNotesRefPattern)
+	err := repo.runGitCommandInline("fetch", remote, fetchRefSpec)
+	if err != nil {
+		return err
+	}
+
+	return repo.mergeRemoteNotes(remote, notesRefPattern)
+}
+
+func getRemoteArchiveRef(remote, archiveRefPattern string) string {
+	relativeArchiveRef := strings.TrimPrefix(archiveRefPattern, "refs/devtools/archives/")
+	return "refs/devtools/remoteArchives/" + remote + "/" + relativeArchiveRef
+}
+
+func (repo *GitRepo) mergeRemoteArchives(remote, archiveRefPattern string) error {
+	remoteRefs, err := repo.runGitCommand("ls-remote", remote, archiveRefPattern)
+	if err != nil {
+		return err
+	}
+	for _, line := range strings.Split(remoteRefs, "\n") {
+		lineParts := strings.Split(line, "\t")
+		if len(lineParts) == 2 {
+			ref := lineParts[1]
+			remoteRef := getRemoteArchiveRef(remote, ref)
+			if err := repo.mergeArchives(ref, remoteRef); err != nil {
+				return err
+			}
+		}
+	}
+	return nil
+}
+
+// PullNotesAndArchive fetches the contents of the notes and archives refs from
+// a remote repo, and merges them with the corresponding local refs.
+//
+// For notes refs, we assume that every note can be automatically merged using
+// the 'cat_sort_uniq' strategy (the git-appraise schemas fit that requirement),
+// so we automatically merge the remote notes into the local notes.
+//
+// For "archive" refs, they are expected to be used solely for maintaining
+// reachability of commits that are part of the history of any reviews,
+// so we do not maintain any consistency with their tree objects. Instead,
+// we merely ensure that their history graph includes every commit that we
+// intend to keep.
+func (repo *GitRepo) PullNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	remoteArchiveRef := getRemoteArchiveRef(remote, archiveRefPattern)
+	archiveFetchRefSpec := fmt.Sprintf("+%s:%s", archiveRefPattern, remoteArchiveRef)
+
+	remoteNotesRefPattern := getRemoteNotesRef(remote, notesRefPattern)
+	notesFetchRefSpec := fmt.Sprintf("+%s:%s", notesRefPattern, remoteNotesRefPattern)
+
+	err := repo.runGitCommandInline("fetch", remote, notesFetchRefSpec, archiveFetchRefSpec)
+	if err != nil {
+		return err
+	}
+
+	if err := repo.mergeRemoteNotes(remote, notesRefPattern); err != nil {
+		return err
+	}
+	if err := repo.mergeRemoteArchives(remote, archiveRefPattern); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/vendor/github.com/google/git-appraise/repository/mock_repo.go b/vendor/github.com/google/git-appraise/repository/mock_repo.go
new file mode 100644
index 0000000000000..c9fd105b91c0c
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/repository/mock_repo.go
@@ -0,0 +1,568 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package repository
+
+import (
+	"crypto/sha1"
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// Constants used for testing.
+// We initialize our mock repo with two branches (one of which holds a pending review),
+// and commit history that looks like this:
+//
+//  Master Branch:    A--B--D--E--F--J
+//                     \   /    \  \
+//                       C       \  \
+//                                \  \
+//  Review Branch:                 G--H--I
+//
+// Where commits "B" and "D" represent reviews that have been submitted, and "G"
+// is a pending review.
+const (
+	TestTargetRef          = "refs/heads/master"
+	TestReviewRef          = "refs/heads/ojarjur/mychange"
+	TestAlternateReviewRef = "refs/review/mychange"
+	TestRequestsRef        = "refs/notes/devtools/reviews"
+	TestCommentsRef        = "refs/notes/devtools/discuss"
+
+	TestCommitA = "A"
+	TestCommitB = "B"
+	TestCommitC = "C"
+	TestCommitD = "D"
+	TestCommitE = "E"
+	TestCommitF = "F"
+	TestCommitG = "G"
+	TestCommitH = "H"
+	TestCommitI = "I"
+	TestCommitJ = "J"
+
+	TestRequestB = `{"timestamp": "0000000001", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "B"}`
+	TestRequestD = `{"timestamp": "0000000002", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "D"}`
+	TestRequestG = `{"timestamp": "0000000004", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "G"}
+
+{"timestamp": "0000000005", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "Updated description of G"}
+
+{"timestamp": "0000000005", "reviewRef": "refs/heads/ojarjur/mychange", "targetRef": "refs/heads/master", "requester": "ojarjur", "reviewers": ["ojarjur"], "description": "Final description of G"}`
+
+	TestDiscussB = `{"timestamp": "0000000001", "author": "ojarjur", "location": {"commit": "B"}, "resolved": true}`
+	TestDiscussD = `{"timestamp": "0000000003", "author": "ojarjur", "location": {"commit": "E"}, "resolved": true}`
+)
+
+type mockCommit struct {
+	Message string   `json:"message,omitempty"`
+	Time    string   `json:"time,omitempty"`
+	Parents []string `json:"parents,omitempty"`
+}
+
+// mockRepoForTest defines an instance of Repo that can be used for testing.
+type mockRepoForTest struct {
+	Head    string
+	Refs    map[string]string            `json:"refs,omitempty"`
+	Commits map[string]mockCommit        `json:"commits,omitempty"`
+	Notes   map[string]map[string]string `json:"notes,omitempty"`
+}
+
+func (r *mockRepoForTest) createCommit(message string, time string, parents []string) (string, error) {
+	newCommit := mockCommit{
+		Message: message,
+		Time:    time,
+		Parents: parents,
+	}
+	newCommitJSON, err := json.Marshal(newCommit)
+	if err != nil {
+		return "", err
+	}
+	newCommitHash := fmt.Sprintf("%x", sha1.Sum([]byte(newCommitJSON)))
+	r.Commits[newCommitHash] = newCommit
+	return newCommitHash, nil
+}
+
+// NewMockRepoForTest returns a mocked-out instance of the Repo interface that has been pre-populated with test data.
+func NewMockRepoForTest() Repo {
+	commitA := mockCommit{
+		Message: "First commit",
+		Time:    "0",
+		Parents: nil,
+	}
+	commitB := mockCommit{
+		Message: "Second commit",
+		Time:    "1",
+		Parents: []string{TestCommitA},
+	}
+	commitC := mockCommit{
+		Message: "No, I'm the second commit",
+		Time:    "1",
+		Parents: []string{TestCommitA},
+	}
+	commitD := mockCommit{
+		Message: "Fourth commit",
+		Time:    "2",
+		Parents: []string{TestCommitB, TestCommitC},
+	}
+	commitE := mockCommit{
+		Message: "Fifth commit",
+		Time:    "3",
+		Parents: []string{TestCommitD},
+	}
+	commitF := mockCommit{
+		Message: "Sixth commit",
+		Time:    "4",
+		Parents: []string{TestCommitE},
+	}
+	commitG := mockCommit{
+		Message: "No, I'm the sixth commit",
+		Time:    "4",
+		Parents: []string{TestCommitE},
+	}
+	commitH := mockCommit{
+		Message: "Seventh commit",
+		Time:    "5",
+		Parents: []string{TestCommitG, TestCommitF},
+	}
+	commitI := mockCommit{
+		Message: "Eighth commit",
+		Time:    "6",
+		Parents: []string{TestCommitH},
+	}
+	commitJ := mockCommit{
+		Message: "No, I'm the eighth commit",
+		Time:    "6",
+		Parents: []string{TestCommitF},
+	}
+	return &mockRepoForTest{
+		Head: TestTargetRef,
+		Refs: map[string]string{
+			TestTargetRef:          TestCommitJ,
+			TestReviewRef:          TestCommitI,
+			TestAlternateReviewRef: TestCommitI,
+		},
+		Commits: map[string]mockCommit{
+			TestCommitA: commitA,
+			TestCommitB: commitB,
+			TestCommitC: commitC,
+			TestCommitD: commitD,
+			TestCommitE: commitE,
+			TestCommitF: commitF,
+			TestCommitG: commitG,
+			TestCommitH: commitH,
+			TestCommitI: commitI,
+			TestCommitJ: commitJ,
+		},
+		Notes: map[string]map[string]string{
+			TestRequestsRef: map[string]string{
+				TestCommitB: TestRequestB,
+				TestCommitD: TestRequestD,
+				TestCommitG: TestRequestG,
+			},
+			TestCommentsRef: map[string]string{
+				TestCommitB: TestDiscussB,
+				TestCommitD: TestDiscussD,
+			},
+		},
+	}
+}
+
+// GetPath returns the path to the repo.
+func (r *mockRepoForTest) GetPath() string { return "~/mockRepo/" }
+
+// GetRepoStateHash returns a hash which embodies the entire current state of a repository.
+func (r *mockRepoForTest) GetRepoStateHash() (string, error) {
+	repoJSON, err := json.Marshal(r)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("%x", sha1.Sum([]byte(repoJSON))), nil
+}
+
+// GetUserEmail returns the email address that the user has used to configure git.
+func (r *mockRepoForTest) GetUserEmail() (string, error) { return "user@example.com", nil }
+
+// GetCoreEditor returns the name of the editor that the user has used to configure git.
+func (r *mockRepoForTest) GetCoreEditor() (string, error) { return "vi", nil }
+
+// GetSubmitStrategy returns the way in which a review is submitted
+func (r *mockRepoForTest) GetSubmitStrategy() (string, error) { return "merge", nil }
+
+// HasUncommittedChanges returns true if there are local, uncommitted changes.
+func (r *mockRepoForTest) HasUncommittedChanges() (bool, error) { return false, nil }
+
+func (r *mockRepoForTest) resolveLocalRef(ref string) (string, error) {
+	if ref == "HEAD" {
+		ref = r.Head
+	}
+	if commit, ok := r.Refs[ref]; ok {
+		return commit, nil
+	}
+	if _, ok := r.Commits[ref]; ok {
+		return ref, nil
+	}
+	return "", fmt.Errorf("The ref %q does not exist", ref)
+}
+
+// VerifyCommit verifies that the supplied hash points to a known commit.
+func (r *mockRepoForTest) VerifyCommit(hash string) error {
+	if _, ok := r.Commits[hash]; !ok {
+		return fmt.Errorf("The given hash %q is not a known commit", hash)
+	}
+	return nil
+}
+
+// VerifyGitRef verifies that the supplied ref points to a known commit.
+func (r *mockRepoForTest) VerifyGitRef(ref string) error {
+	_, err := r.resolveLocalRef(ref)
+	return err
+}
+
+// GetHeadRef returns the ref that is the current HEAD.
+func (r *mockRepoForTest) GetHeadRef() (string, error) { return r.Head, nil }
+
+// GetCommitHash returns the hash of the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitHash(ref string) (string, error) {
+	err := r.VerifyGitRef(ref)
+	if err != nil {
+		return "", err
+	}
+	return r.resolveLocalRef(ref)
+}
+
+// ResolveRefCommit returns the commit pointed to by the given ref, which may be a remote ref.
+//
+// This differs from GetCommitHash which only works on exact matches, in that it will try to
+// intelligently handle the scenario of a ref not existing locally, but being known to exist
+// in a remote repo.
+//
+// This method should be used when a command may be performed by either the reviewer or the
+// reviewee, while GetCommitHash should be used when the encompassing command should only be
+// performed by the reviewee.
+func (r *mockRepoForTest) ResolveRefCommit(ref string) (string, error) {
+	if commit, err := r.resolveLocalRef(ref); err == nil {
+		return commit, err
+	}
+	return r.resolveLocalRef(strings.Replace(ref, "refs/heads/", "refs/remotes/origin/", 1))
+}
+
+func (r *mockRepoForTest) getCommit(ref string) (mockCommit, error) {
+	commit, err := r.resolveLocalRef(ref)
+	return r.Commits[commit], err
+}
+
+// GetCommitMessage returns the message stored in the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitMessage(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return "", err
+	}
+	return commit.Message, nil
+}
+
+// GetCommitTime returns the commit time of the commit pointed to by the given ref.
+func (r *mockRepoForTest) GetCommitTime(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return "", err
+	}
+	return commit.Time, nil
+}
+
+// GetLastParent returns the last parent of the given commit (as ordered by git).
+func (r *mockRepoForTest) GetLastParent(ref string) (string, error) {
+	commit, err := r.getCommit(ref)
+	if len(commit.Parents) > 0 {
+		return commit.Parents[len(commit.Parents)-1], err
+	}
+	return "", err
+}
+
+// GetCommitDetails returns the details of a commit's metadata.
+func (r *mockRepoForTest) GetCommitDetails(ref string) (*CommitDetails, error) {
+	commit, err := r.getCommit(ref)
+	if err != nil {
+		return nil, err
+	}
+	var details CommitDetails
+	details.Author = "Test Author"
+	details.AuthorEmail = "author@example.com"
+	details.Summary = commit.Message
+	details.Time = commit.Time
+	details.Parents = commit.Parents
+	return &details, nil
+}
+
+// ancestors returns the breadth-first traversal of a commit's ancestors
+func (r *mockRepoForTest) ancestors(commit string) ([]string, error) {
+	queue := []string{commit}
+	var ancestors []string
+	for queue != nil {
+		var nextQueue []string
+		for _, c := range queue {
+			commit, err := r.getCommit(c)
+			if err != nil {
+				return nil, err
+			}
+			parents := commit.Parents
+			nextQueue = append(nextQueue, parents...)
+			ancestors = append(ancestors, parents...)
+		}
+		queue = nextQueue
+	}
+	return ancestors, nil
+}
+
+// IsAncestor determines if the first argument points to a commit that is an ancestor of the second.
+func (r *mockRepoForTest) IsAncestor(ancestor, descendant string) (bool, error) {
+	var err error
+	ancestor, err = r.resolveLocalRef(ancestor)
+	if err != nil {
+		return false, err
+	}
+	descendant, err = r.resolveLocalRef(descendant)
+	if err != nil {
+		return false, err
+	}
+	if ancestor == descendant {
+		return true, nil
+	}
+	descendantCommit, err := r.getCommit(descendant)
+	if err != nil {
+		return false, err
+	}
+	for _, parent := range descendantCommit.Parents {
+		if t, e := r.IsAncestor(ancestor, parent); e == nil && t {
+			return true, nil
+		}
+	}
+	return false, nil
+}
+
+// MergeBase determines if the first commit that is an ancestor of the two arguments.
+func (r *mockRepoForTest) MergeBase(a, b string) (string, error) {
+	ancestors, err := r.ancestors(a)
+	if err != nil {
+		return "", err
+	}
+	for _, ancestor := range ancestors {
+		if t, e := r.IsAncestor(ancestor, b); e == nil && t {
+			return ancestor, nil
+		}
+	}
+	return "", nil
+}
+
+// Diff computes the diff between two given commits.
+func (r *mockRepoForTest) Diff(left, right string, diffArgs ...string) (string, error) {
+	return fmt.Sprintf("Diff between %q and %q", left, right), nil
+}
+
+// Show returns the contents of the given file at the given commit.
+func (r *mockRepoForTest) Show(commit, path string) (string, error) {
+	return fmt.Sprintf("%s:%s", commit, path), nil
+}
+
+// SwitchToRef changes the currently-checked-out ref.
+func (r *mockRepoForTest) SwitchToRef(ref string) error {
+	r.Head = ref
+	return nil
+}
+
+// ArchiveRef adds the current commit pointed to by the 'ref' argument
+// under the ref specified in the 'archive' argument.
+//
+// Both the 'ref' and 'archive' arguments are expected to be the fully
+// qualified names of git refs (e.g. 'refs/heads/my-change' or
+// 'refs/archive/devtools').
+//
+// If the ref pointed to by the 'archive' argument does not exist
+// yet, then it will be created.
+func (r *mockRepoForTest) ArchiveRef(ref, archive string) error {
+	commitToArchive, err := r.resolveLocalRef(ref)
+	if err != nil {
+		return err
+	}
+	var archiveParents []string
+	if archiveCommit, err := r.resolveLocalRef(archive); err == nil {
+		archiveParents = []string{archiveCommit, commitToArchive}
+	} else {
+		archiveParents = []string{commitToArchive}
+	}
+	archiveCommit, err := r.createCommit("Archiving", "Nowish", archiveParents)
+	if err != nil {
+		return err
+	}
+	r.Refs[archive] = archiveCommit
+	return nil
+}
+
+// MergeRef merges the given ref into the current one.
+//
+// The ref argument is the ref to merge, and fastForward indicates that the
+// current ref should only move forward, as opposed to creating a bubble merge.
+func (r *mockRepoForTest) MergeRef(ref string, fastForward bool, messages ...string) error {
+	newCommitHash, err := r.resolveLocalRef(ref)
+	if err != nil {
+		return err
+	}
+	if !fastForward {
+		origCommit, err := r.resolveLocalRef(r.Head)
+		if err != nil {
+			return err
+		}
+		newCommit, err := r.getCommit(ref)
+		if err != nil {
+			return err
+		}
+		message := strings.Join(messages, "\n\n")
+		time := newCommit.Time
+		parents := []string{origCommit, newCommitHash}
+		newCommitHash, err = r.createCommit(message, time, parents)
+		if err != nil {
+			return err
+		}
+	}
+	r.Refs[r.Head] = newCommitHash
+	return nil
+}
+
+// RebaseRef rebases the current ref onto the given one.
+func (r *mockRepoForTest) RebaseRef(ref string) error {
+	parentHash := r.Refs[ref]
+	origCommit, err := r.getCommit(r.Head)
+	if err != nil {
+		return err
+	}
+	newCommitHash, err := r.createCommit(origCommit.Message, origCommit.Time, []string{parentHash})
+	if err != nil {
+		return err
+	}
+	if strings.HasPrefix(r.Head, "refs/heads/") {
+		r.Refs[r.Head] = newCommitHash
+	} else {
+		// The current head is not a branch, so updating
+		// it should leave us in a detached-head state.
+		r.Head = newCommitHash
+	}
+	return nil
+}
+
+// ListCommits returns the list of commits reachable from the given ref.
+//
+// The generated list is in chronological order (with the oldest commit first).
+//
+// If the specified ref does not exist, then this method returns an empty result.
+func (r *mockRepoForTest) ListCommits(ref string) []string { return nil }
+
+// ListCommitsBetween returns the list of commits between the two given revisions.
+//
+// The "from" parameter is the starting point (exclusive), and the "to"
+// parameter is the ending point (inclusive).
+//
+// The "from" commit does not need to be an ancestor of the "to" commit. If it
+// is not, then the merge base of the two is used as the starting point.
+// Admittedly, this makes calling these the "between" commits is a bit of a
+// misnomer, but it also makes the method easier to use when you want to
+// generate the list of changes in a feature branch, as it eliminates the need
+// to explicitly calculate the merge base. This also makes the semantics of the
+// method compatible with git's built-in "rev-list" command.
+//
+// The generated list is in chronological order (with the oldest commit first).
+func (r *mockRepoForTest) ListCommitsBetween(from, to string) ([]string, error) {
+	commits := []string{to}
+	potentialCommits, _ := r.ancestors(to)
+	for _, commit := range potentialCommits {
+		blocked, err := r.IsAncestor(commit, from)
+		if err != nil {
+			return nil, err
+		}
+		if !blocked {
+			commits = append(commits, commit)
+		}
+	}
+	return commits, nil
+}
+
+// GetNotes reads the notes from the given ref that annotate the given revision.
+func (r *mockRepoForTest) GetNotes(notesRef, revision string) []Note {
+	notesText := r.Notes[notesRef][revision]
+	var notes []Note
+	for _, line := range strings.Split(notesText, "\n") {
+		notes = append(notes, Note(line))
+	}
+	return notes
+}
+
+// GetAllNotes reads the contents of the notes under the given ref for every commit.
+//
+// The returned value is a mapping from commit hash to the list of notes for that commit.
+//
+// This is the batch version of the corresponding GetNotes(...) method.
+func (r *mockRepoForTest) GetAllNotes(notesRef string) (map[string][]Note, error) {
+	notesMap := make(map[string][]Note)
+	for _, commit := range r.ListNotedRevisions(notesRef) {
+		notesMap[commit] = r.GetNotes(notesRef, commit)
+	}
+	return notesMap, nil
+}
+
+// AppendNote appends a note to a revision under the given ref.
+func (r *mockRepoForTest) AppendNote(ref, revision string, note Note) error {
+	existingNotes := r.Notes[ref][revision]
+	newNotes := existingNotes + "\n" + string(note)
+	r.Notes[ref][revision] = newNotes
+	return nil
+}
+
+// ListNotedRevisions returns the collection of revisions that are annotated by notes in the given ref.
+func (r *mockRepoForTest) ListNotedRevisions(notesRef string) []string {
+	var revisions []string
+	for revision := range r.Notes[notesRef] {
+		if _, ok := r.Commits[revision]; ok {
+			revisions = append(revisions, revision)
+		}
+	}
+	return revisions
+}
+
+// PushNotes pushes git notes to a remote repo.
+func (r *mockRepoForTest) PushNotes(remote, notesRefPattern string) error { return nil }
+
+// PullNotes fetches the contents of the given notes ref from a remote repo,
+// and then merges them with the corresponding local notes using the
+// "cat_sort_uniq" strategy.
+func (r *mockRepoForTest) PullNotes(remote, notesRefPattern string) error { return nil }
+
+// PushNotesAndArchive pushes the given notes and archive refs to a remote repo.
+func (r *mockRepoForTest) PushNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	return nil
+}
+
+// PullNotesAndArchive fetches the contents of the notes and archives refs from
+// a remote repo, and merges them with the corresponding local refs.
+//
+// For notes refs, we assume that every note can be automatically merged using
+// the 'cat_sort_uniq' strategy (the git-appraise schemas fit that requirement),
+// so we automatically merge the remote notes into the local notes.
+//
+// For "archive" refs, they are expected to be used solely for maintaining
+// reachability of commits that are part of the history of any reviews,
+// so we do not maintain any consistency with their tree objects. Instead,
+// we merely ensure that their history graph includes every commit that we
+// intend to keep.
+func (r *mockRepoForTest) PullNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error {
+	return nil
+}
diff --git a/vendor/github.com/google/git-appraise/repository/repo.go b/vendor/github.com/google/git-appraise/repository/repo.go
new file mode 100644
index 0000000000000..03413e30b24bb
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/repository/repo.go
@@ -0,0 +1,188 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package repository contains helper methods for working with a Git repo.
+package repository
+
+// Note represents the contents of a git-note
+type Note []byte
+
+// CommitDetails represents the contents of a commit.
+type CommitDetails struct {
+	Author      string   `json:"author,omitempty"`
+	AuthorEmail string   `json:"authorEmail,omitempty"`
+	Tree        string   `json:"tree,omitempty"`
+	Time        string   `json:"time,omitempty"`
+	Parents     []string `json:"parents,omitempty"`
+	Summary     string   `json:"summary,omitempty"`
+}
+
+// Repo represents a source code repository.
+type Repo interface {
+	// GetPath returns the path to the repo.
+	GetPath() string
+
+	// GetRepoStateHash returns a hash which embodies the entire current state of a repository.
+	GetRepoStateHash() (string, error)
+
+	// GetUserEmail returns the email address that the user has used to configure git.
+	GetUserEmail() (string, error)
+
+	// GetCoreEditor returns the name of the editor that the user has used to configure git.
+	GetCoreEditor() (string, error)
+
+	// GetSubmitStrategy returns the way in which a review is submitted
+	GetSubmitStrategy() (string, error)
+
+	// HasUncommittedChanges returns true if there are local, uncommitted changes.
+	HasUncommittedChanges() (bool, error)
+
+	// VerifyCommit verifies that the supplied hash points to a known commit.
+	VerifyCommit(hash string) error
+
+	// VerifyGitRef verifies that the supplied ref points to a known commit.
+	VerifyGitRef(ref string) error
+
+	// GetHeadRef returns the ref that is the current HEAD.
+	GetHeadRef() (string, error)
+
+	// GetCommitHash returns the hash of the commit pointed to by the given ref.
+	GetCommitHash(ref string) (string, error)
+
+	// ResolveRefCommit returns the commit pointed to by the given ref, which may be a remote ref.
+	//
+	// This differs from GetCommitHash which only works on exact matches, in that it will try to
+	// intelligently handle the scenario of a ref not existing locally, but being known to exist
+	// in a remote repo.
+	//
+	// This method should be used when a command may be performed by either the reviewer or the
+	// reviewee, while GetCommitHash should be used when the encompassing command should only be
+	// performed by the reviewee.
+	ResolveRefCommit(ref string) (string, error)
+
+	// GetCommitMessage returns the message stored in the commit pointed to by the given ref.
+	GetCommitMessage(ref string) (string, error)
+
+	// GetCommitTime returns the commit time of the commit pointed to by the given ref.
+	GetCommitTime(ref string) (string, error)
+
+	// GetLastParent returns the last parent of the given commit (as ordered by git).
+	GetLastParent(ref string) (string, error)
+
+	// GetCommitDetails returns the details of a commit's metadata.
+	GetCommitDetails(ref string) (*CommitDetails, error)
+
+	// MergeBase determines if the first commit that is an ancestor of the two arguments.
+	MergeBase(a, b string) (string, error)
+
+	// IsAncestor determines if the first argument points to a commit that is an ancestor of the second.
+	IsAncestor(ancestor, descendant string) (bool, error)
+
+	// Diff computes the diff between two given commits.
+	Diff(left, right string, diffArgs ...string) (string, error)
+
+	// Show returns the contents of the given file at the given commit.
+	Show(commit, path string) (string, error)
+
+	// SwitchToRef changes the currently-checked-out ref.
+	SwitchToRef(ref string) error
+
+	// ArchiveRef adds the current commit pointed to by the 'ref' argument
+	// under the ref specified in the 'archive' argument.
+	//
+	// Both the 'ref' and 'archive' arguments are expected to be the fully
+	// qualified names of git refs (e.g. 'refs/heads/my-change' or
+	// 'refs/archive/devtools').
+	//
+	// If the ref pointed to by the 'archive' argument does not exist
+	// yet, then it will be created.
+	ArchiveRef(ref, archive string) error
+
+	// MergeRef merges the given ref into the current one.
+	//
+	// The ref argument is the ref to merge, and fastForward indicates that the
+	// current ref should only move forward, as opposed to creating a bubble merge.
+	// The messages argument(s) provide text that should be included in the default
+	// merge commit message (separated by blank lines).
+	MergeRef(ref string, fastForward bool, messages ...string) error
+
+	// RebaseRef rebases the current ref onto the given one.
+	RebaseRef(ref string) error
+
+	// ListCommits returns the list of commits reachable from the given ref.
+	//
+	// The generated list is in chronological order (with the oldest commit first).
+	//
+	// If the specified ref does not exist, then this method returns an empty result.
+	ListCommits(ref string) []string
+
+	// ListCommitsBetween returns the list of commits between the two given revisions.
+	//
+	// The "from" parameter is the starting point (exclusive), and the "to"
+	// parameter is the ending point (inclusive).
+	//
+	// The "from" commit does not need to be an ancestor of the "to" commit. If it
+	// is not, then the merge base of the two is used as the starting point.
+	// Admittedly, this makes calling these the "between" commits is a bit of a
+	// misnomer, but it also makes the method easier to use when you want to
+	// generate the list of changes in a feature branch, as it eliminates the need
+	// to explicitly calculate the merge base. This also makes the semantics of the
+	// method compatible with git's built-in "rev-list" command.
+	//
+	// The generated list is in chronological order (with the oldest commit first).
+	ListCommitsBetween(from, to string) ([]string, error)
+
+	// GetNotes reads the notes from the given ref that annotate the given revision.
+	GetNotes(notesRef, revision string) []Note
+
+	// GetAllNotes reads the contents of the notes under the given ref for every commit.
+	//
+	// The returned value is a mapping from commit hash to the list of notes for that commit.
+	//
+	// This is the batch version of the corresponding GetNotes(...) method.
+	GetAllNotes(notesRef string) (map[string][]Note, error)
+
+	// AppendNote appends a note to a revision under the given ref.
+	AppendNote(ref, revision string, note Note) error
+
+	// ListNotedRevisions returns the collection of revisions that are annotated by notes in the given ref.
+	ListNotedRevisions(notesRef string) []string
+
+	// PushNotes pushes git notes to a remote repo.
+	PushNotes(remote, notesRefPattern string) error
+
+	// PullNotes fetches the contents of the given notes ref from a remote repo,
+	// and then merges them with the corresponding local notes using the
+	// "cat_sort_uniq" strategy.
+	PullNotes(remote, notesRefPattern string) error
+
+	// PushNotesAndArchive pushes the given notes and archive refs to a remote repo.
+	PushNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error
+
+	// PullNotesAndArchive fetches the contents of the notes and archives refs from
+	// a remote repo, and merges them with the corresponding local refs.
+	//
+	// For notes refs, we assume that every note can be automatically merged using
+	// the 'cat_sort_uniq' strategy (the git-appraise schemas fit that requirement),
+	// so we automatically merge the remote notes into the local notes.
+	//
+	// For "archive" refs, they are expected to be used solely for maintaining
+	// reachability of commits that are part of the history of any reviews,
+	// so we do not maintain any consistency with their tree objects. Instead,
+	// we merely ensure that their history graph includes every commit that we
+	// intend to keep.
+	PullNotesAndArchive(remote, notesRefPattern, archiveRefPattern string) error
+}
diff --git a/vendor/github.com/google/git-appraise/review/analyses/analyses.go b/vendor/github.com/google/git-appraise/review/analyses/analyses.go
new file mode 100644
index 0000000000000..a2497d3bf8615
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/review/analyses/analyses.go
@@ -0,0 +1,156 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package analyses defines the internal representation of static analysis reports.
+package analyses
+
+import (
+	"encoding/json"
+	"github.com/google/git-appraise/repository"
+	"io/ioutil"
+	"net/http"
+	"sort"
+	"strconv"
+)
+
+const (
+	// Ref defines the git-notes ref that we expect to contain analysis reports.
+	Ref = "refs/notes/devtools/analyses"
+
+	// StatusLooksGoodToMe is the status string representing that analyses reported no messages.
+	StatusLooksGoodToMe = "lgtm"
+	// StatusForYourInformation is the status string representing that analyses reported informational messages.
+	StatusForYourInformation = "fyi"
+	// StatusNeedsMoreWork is the status string representing that analyses reported error messages.
+	StatusNeedsMoreWork = "nmw"
+
+	// FormatVersion defines the latest version of the request format supported by the tool.
+	FormatVersion = 0
+)
+
+// Report represents a build/test status report generated by analyses tool.
+// Every field is optional.
+type Report struct {
+	Timestamp string `json:"timestamp,omitempty"`
+	URL       string `json:"url,omitempty"`
+	Status    string `json:"status,omitempty"`
+	// Version represents the version of the metadata format.
+	Version int `json:"v,omitempty"`
+}
+
+// LocationRange represents the location within a source file that an analysis message covers.
+type LocationRange struct {
+	StartLine int `json:"start_line,omitempty"`
+}
+
+// Location represents the location within a source tree that an analysis message covers.
+type Location struct {
+	Path  string         `json:"path,omitempty"`
+	Range *LocationRange `json:"range,omitempty"`
+}
+
+// Note represents a single analysis message.
+type Note struct {
+	Location    *Location `json:"location,omitempty"`
+	Category    string    `json:"category,omitempty"`
+	Description string    `json:"description"`
+}
+
+// AnalyzeResponse represents the response from a static-analysis tool.
+type AnalyzeResponse struct {
+	Notes []Note `json:"note,omitempty"`
+}
+
+// ReportDetails represents an entire static analysis run (which might include multiple analysis tools).
+type ReportDetails struct {
+	AnalyzeResponse []AnalyzeResponse `json:"analyze_response,omitempty"`
+}
+
+// GetLintReportResult downloads the details of a lint report and returns the responses embedded in it.
+func (analysesReport Report) GetLintReportResult() ([]AnalyzeResponse, error) {
+	if analysesReport.URL == "" {
+		return nil, nil
+	}
+	res, err := http.Get(analysesReport.URL)
+	if err != nil {
+		return nil, err
+	}
+	analysesResults, err := ioutil.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		return nil, err
+	}
+	var details ReportDetails
+	err = json.Unmarshal([]byte(analysesResults), &details)
+	if err != nil {
+		return nil, err
+	}
+	return details.AnalyzeResponse, nil
+}
+
+// GetNotes downloads the details of an analyses report and returns the notes embedded in it.
+func (analysesReport Report) GetNotes() ([]Note, error) {
+	reportResults, err := analysesReport.GetLintReportResult()
+	if err != nil {
+		return nil, err
+	}
+	var reportNotes []Note
+	for _, reportResult := range reportResults {
+		reportNotes = append(reportNotes, reportResult.Notes...)
+	}
+	return reportNotes, nil
+}
+
+// Parse parses an analysis report from a git note.
+func Parse(note repository.Note) (Report, error) {
+	bytes := []byte(note)
+	var report Report
+	err := json.Unmarshal(bytes, &report)
+	return report, err
+}
+
+// GetLatestAnalysesReport takes a collection of analysis reports, and returns the one with the most recent timestamp.
+func GetLatestAnalysesReport(reports []Report) (*Report, error) {
+	timestampReportMap := make(map[int]*Report)
+	var timestamps []int
+
+	for _, report := range reports {
+		timestamp, err := strconv.Atoi(report.Timestamp)
+		if err != nil {
+			return nil, err
+		}
+		timestamps = append(timestamps, timestamp)
+		timestampReportMap[timestamp] = &report
+	}
+	if len(timestamps) == 0 {
+		return nil, nil
+	}
+	sort.Sort(sort.Reverse(sort.IntSlice(timestamps)))
+	return timestampReportMap[timestamps[0]], nil
+}
+
+// ParseAllValid takes collection of git notes and tries to parse a analyses report
+// from each one. Any notes that are not valid analyses reports get ignored.
+func ParseAllValid(notes []repository.Note) []Report {
+	var reports []Report
+	for _, note := range notes {
+		report, err := Parse(note)
+		if err == nil && report.Version == FormatVersion {
+			reports = append(reports, report)
+		}
+	}
+	return reports
+}
diff --git a/vendor/github.com/google/git-appraise/review/ci/ci.go b/vendor/github.com/google/git-appraise/review/ci/ci.go
new file mode 100644
index 0000000000000..b2cfd22743c2c
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/review/ci/ci.go
@@ -0,0 +1,95 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package ci defines the internal representation of a continuous integration reports.
+package ci
+
+import (
+	"encoding/json"
+	"github.com/google/git-appraise/repository"
+	"sort"
+	"strconv"
+)
+
+const (
+	// Ref defines the git-notes ref that we expect to contain CI reports.
+	Ref = "refs/notes/devtools/ci"
+
+	// StatusSuccess is the status string representing that a build and/or test passed.
+	StatusSuccess = "success"
+	// StatusFailure is the status string representing that a build and/or test failed.
+	StatusFailure = "failure"
+
+	// FormatVersion defines the latest version of the request format supported by the tool.
+	FormatVersion = 0
+)
+
+// Report represents a build/test status report generated by a continuous integration tool.
+//
+// Every field is optional.
+type Report struct {
+	Timestamp string `json:"timestamp,omitempty"`
+	URL       string `json:"url,omitempty"`
+	Status    string `json:"status,omitempty"`
+	Agent     string `json:"agent,omitempty"`
+	// Version represents the version of the metadata format.
+	Version int `json:"v,omitempty"`
+}
+
+// Parse parses a CI report from a git note.
+func Parse(note repository.Note) (Report, error) {
+	bytes := []byte(note)
+	var report Report
+	err := json.Unmarshal(bytes, &report)
+	return report, err
+}
+
+// GetLatestCIReport takes the collection of reports and returns the one with the most recent timestamp.
+func GetLatestCIReport(reports []Report) (*Report, error) {
+	timestampReportMap := make(map[int]*Report)
+	var timestamps []int
+
+	for _, report := range reports {
+		timestamp, err := strconv.Atoi(report.Timestamp)
+		if err != nil {
+			return nil, err
+		}
+		timestamps = append(timestamps, timestamp)
+		timestampReportMap[timestamp] = &report
+	}
+	if len(timestamps) == 0 {
+		return nil, nil
+	}
+	sort.Sort(sort.Reverse(sort.IntSlice(timestamps)))
+	return timestampReportMap[timestamps[0]], nil
+}
+
+// ParseAllValid takes collection of git notes and tries to parse a CI report
+// from each one. Any notes that are not valid CI reports get ignored, as we
+// expect the git notes to be a heterogenous list, with only some of them
+// being valid CI status reports.
+func ParseAllValid(notes []repository.Note) []Report {
+	var reports []Report
+	for _, note := range notes {
+		report, err := Parse(note)
+		if err == nil && report.Version == FormatVersion {
+			if report.Status == "" || report.Status == StatusSuccess || report.Status == StatusFailure {
+				reports = append(reports, report)
+			}
+		}
+	}
+	return reports
+}
diff --git a/vendor/github.com/google/git-appraise/review/comment/comment.go b/vendor/github.com/google/git-appraise/review/comment/comment.go
new file mode 100644
index 0000000000000..3470686a4d3d3
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/review/comment/comment.go
@@ -0,0 +1,137 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package comment defines the internal representation of a review comment.
+package comment
+
+import (
+	"crypto/sha1"
+	"encoding/json"
+	"fmt"
+	"github.com/google/git-appraise/repository"
+	"strconv"
+	"time"
+)
+
+// Ref defines the git-notes ref that we expect to contain review comments.
+const Ref = "refs/notes/devtools/discuss"
+
+// FormatVersion defines the latest version of the comment format supported by the tool.
+const FormatVersion = 0
+
+// Range represents the range of text that is under discussion.
+type Range struct {
+	StartLine uint32 `json:"startLine"`
+}
+
+// Location represents the location of a comment within a commit.
+type Location struct {
+	Commit string `json:"commit,omitempty"`
+	// If the path is omitted, then the comment applies to the entire commit.
+	Path string `json:"path,omitempty"`
+	// If the range is omitted, then the location represents an entire file.
+	Range *Range `json:"range,omitempty"`
+}
+
+// Comment represents a review comment, and can occur in any of the following contexts:
+// 1. As a comment on an entire commit.
+// 2. As a comment about a specific file in a commit.
+// 3. As a comment about a specific line in a commit.
+// 4. As a response to another comment.
+type Comment struct {
+	// Timestamp and Author are optimizations that allows us to display comment threads
+	// without having to run git-blame over the notes object. This is done because
+	// git-blame will become more and more expensive as the number of code reviews grows.
+	Timestamp string `json:"timestamp,omitempty"`
+	Author    string `json:"author,omitempty"`
+	// If parent is provided, then the comment is a response to another comment.
+	Parent string `json:"parent,omitempty"`
+	// If location is provided, then the comment is specific to that given location.
+	Location    *Location `json:"location,omitempty"`
+	Description string    `json:"description,omitempty"`
+	// The resolved bit indicates that no further action is needed.
+	//
+	// When the parent of the comment is another comment, this means that comment
+	// has been addressed. Otherwise, the parent is the commit, and this means that the
+	// change has been accepted. If the resolved bit is unset, then the comment is only an FYI.
+	Resolved *bool `json:"resolved,omitempty"`
+	// Version represents the version of the metadata format.
+	Version int `json:"v,omitempty"`
+}
+
+// New returns a new comment with the given description message.
+//
+// The Timestamp and Author fields are automatically filled in with the current time and user.
+func New(author string, description string) Comment {
+	return Comment{
+		Timestamp:   strconv.FormatInt(time.Now().Unix(), 10),
+		Author:      author,
+		Description: description,
+	}
+}
+
+// Parse parses a review comment from a git note.
+func Parse(note repository.Note) (Comment, error) {
+	bytes := []byte(note)
+	var comment Comment
+	err := json.Unmarshal(bytes, &comment)
+	return comment, err
+}
+
+// ParseAllValid takes collection of git notes and tries to parse a review
+// comment from each one. Any notes that are not valid review comments get
+// ignored, as we expect the git notes to be a heterogenous list, with only
+// some of them being review comments.
+func ParseAllValid(notes []repository.Note) map[string]Comment {
+	comments := make(map[string]Comment)
+	for _, note := range notes {
+		comment, err := Parse(note)
+		if err == nil && comment.Version == FormatVersion {
+			hash, err := comment.Hash()
+			if err == nil {
+				comments[hash] = comment
+			}
+		}
+	}
+	return comments
+}
+
+func (comment Comment) serialize() ([]byte, error) {
+	if len(comment.Timestamp) < 10 {
+		// To make sure that timestamps from before 2001 appear in the correct
+		// alphabetical order, we reformat the timestamp to be at least 10 characters
+		// and zero-padded.
+		time, err := strconv.ParseInt(comment.Timestamp, 10, 64)
+		if err == nil {
+			comment.Timestamp = fmt.Sprintf("%010d", time)
+		}
+		// We ignore the other case, as the comment timestamp is not in a format
+		// we expected, so we should just leave it alone.
+	}
+	return json.Marshal(comment)
+}
+
+// Write writes a review comment as a JSON-formatted git note.
+func (comment Comment) Write() (repository.Note, error) {
+	bytes, err := comment.serialize()
+	return repository.Note(bytes), err
+}
+
+// Hash returns the SHA1 hash of a review comment.
+func (comment Comment) Hash() (string, error) {
+	bytes, err := comment.serialize()
+	return fmt.Sprintf("%x", sha1.Sum(bytes)), err
+}
diff --git a/vendor/github.com/google/git-appraise/review/request/request.go b/vendor/github.com/google/git-appraise/review/request/request.go
new file mode 100644
index 0000000000000..a4159513996a1
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/review/request/request.go
@@ -0,0 +1,100 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package request defines the internal representation of a review request.
+package request
+
+import (
+	"encoding/json"
+	"github.com/google/git-appraise/repository"
+	"strconv"
+	"time"
+)
+
+// Ref defines the git-notes ref that we expect to contain review requests.
+const Ref = "refs/notes/devtools/reviews"
+
+// FormatVersion defines the latest version of the request format supported by the tool.
+const FormatVersion = 0
+
+// Request represents an initial request for a code review.
+//
+// Every field except for TargetRef is optional.
+type Request struct {
+	// Timestamp and Requester are optimizations that allows us to display reviews
+	// without having to run git-blame over the notes object. This is done because
+	// git-blame will become more and more expensive as the number of reviews grows.
+	Timestamp   string   `json:"timestamp,omitempty"`
+	ReviewRef   string   `json:"reviewRef,omitempty"`
+	TargetRef   string   `json:"targetRef"`
+	Requester   string   `json:"requester,omitempty"`
+	Reviewers   []string `json:"reviewers,omitempty"`
+	Description string   `json:"description,omitempty"`
+	// Version represents the version of the metadata format.
+	Version int `json:"v,omitempty"`
+	// BaseCommit stores the commit ID of the target ref at the time the review was requested.
+	// This is optional, and only used for submitted reviews which were anchored at a merge commit.
+	// This allows someone viewing that submitted review to find the diff against which the
+	// code was reviewed.
+	BaseCommit string `json:"baseCommit,omitempty"`
+	// Alias stores a post-rebase commit ID for the review. This allows the tool
+	// to track the history of a review even if the commit history changes.
+	Alias string `json:"alias,omitempty"`
+}
+
+// New returns a new request.
+//
+// The Timestamp and Requester fields are automatically filled in with the current time and user.
+func New(requester string, reviewers []string, reviewRef, targetRef, description string) Request {
+	return Request{
+		Timestamp:   strconv.FormatInt(time.Now().Unix(), 10),
+		Requester:   requester,
+		Reviewers:   reviewers,
+		ReviewRef:   reviewRef,
+		TargetRef:   targetRef,
+		Description: description,
+	}
+}
+
+// Parse parses a review request from a git note.
+func Parse(note repository.Note) (Request, error) {
+	bytes := []byte(note)
+	var request Request
+	err := json.Unmarshal(bytes, &request)
+	// TODO(ojarjur): If "requester" is not set, then use git-blame to fill it in.
+	return request, err
+}
+
+// ParseAllValid takes collection of git notes and tries to parse a review
+// request from each one. Any notes that are not valid review requests get
+// ignored, as we expect the git notes to be a heterogenous list, with only
+// some of them being review requests.
+func ParseAllValid(notes []repository.Note) []Request {
+	var requests []Request
+	for _, note := range notes {
+		request, err := Parse(note)
+		if err == nil && request.Version == FormatVersion && request.TargetRef != "" {
+			requests = append(requests, request)
+		}
+	}
+	return requests
+}
+
+// Write writes a review request as a JSON-formatted git note.
+func (request *Request) Write() (repository.Note, error) {
+	bytes, err := json.Marshal(request)
+	return repository.Note(bytes), err
+}
diff --git a/vendor/github.com/google/git-appraise/review/review.go b/vendor/github.com/google/git-appraise/review/review.go
new file mode 100644
index 0000000000000..a9fe5661c4eb3
--- /dev/null
+++ b/vendor/github.com/google/git-appraise/review/review.go
@@ -0,0 +1,612 @@
+/*
+Copyright 2015 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+
+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 or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package review contains the data structures used to represent code reviews.
+package review
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"github.com/google/git-appraise/repository"
+	"github.com/google/git-appraise/review/analyses"
+	"github.com/google/git-appraise/review/ci"
+	"github.com/google/git-appraise/review/comment"
+	"github.com/google/git-appraise/review/request"
+	"sort"
+)
+
+const archiveRef = "refs/devtools/archives/reviews"
+
+// CommentThread represents the tree-based hierarchy of comments.
+//
+// The Resolved field represents the aggregate status of the entire thread. If
+// it is set to false, then it indicates that there is an unaddressed comment
+// in the thread. If it is unset, then that means that the root comment is an
+// FYI only, and that there are no unaddressed comments. If it is set to true,
+// then that means that there are no unaddressed comments, and that the root
+// comment has its resolved bit set to true.
+type CommentThread struct {
+	Hash     string          `json:"hash,omitempty"`
+	Comment  comment.Comment `json:"comment"`
+	Children []CommentThread `json:"children,omitempty"`
+	Resolved *bool           `json:"resolved,omitempty"`
+}
+
+// Summary represents the high-level state of a code review.
+//
+// This high-level state corresponds to the data that can be quickly read
+// directly from the repo, so other methods that need to operate on a lot
+// of reviews (such as listing the open reviews) should prefer operating on
+// the summary rather than the details.
+//
+// Review summaries have two status fields which are orthogonal:
+// 1. Resolved indicates if a reviewer has accepted or rejected the change.
+// 2. Submitted indicates if the change has been incorporated into the target.
+type Summary struct {
+	Repo        repository.Repo   `json:"-"`
+	Revision    string            `json:"revision"`
+	Request     request.Request   `json:"request"`
+	AllRequests []request.Request `json:"-"`
+	Comments    []CommentThread   `json:"comments,omitempty"`
+	Resolved    *bool             `json:"resolved,omitempty"`
+	Submitted   bool              `json:"submitted"`
+}
+
+// Review represents the entire state of a code review.
+//
+// This extends Summary to also include a list of reports for both the
+// continuous integration status, and the static analysis runs. Those reports
+// correspond to either the current commit in the review ref (for pending
+// reviews), or to the last commented-upon commit (for submitted reviews).
+type Review struct {
+	*Summary
+	Reports  []ci.Report       `json:"reports,omitempty"`
+	Analyses []analyses.Report `json:"analyses,omitempty"`
+}
+
+type byTimestamp []CommentThread
+
+// Interface methods for sorting comment threads by timestamp
+func (threads byTimestamp) Len() int      { return len(threads) }
+func (threads byTimestamp) Swap(i, j int) { threads[i], threads[j] = threads[j], threads[i] }
+func (threads byTimestamp) Less(i, j int) bool {
+	return threads[i].Comment.Timestamp < threads[j].Comment.Timestamp
+}
+
+type requestsByTimestamp []request.Request
+
+// Interface methods for sorting review requests by timestamp
+func (requests requestsByTimestamp) Len() int { return len(requests) }
+func (requests requestsByTimestamp) Swap(i, j int) {
+	requests[i], requests[j] = requests[j], requests[i]
+}
+func (requests requestsByTimestamp) Less(i, j int) bool {
+	return requests[i].Timestamp < requests[j].Timestamp
+}
+
+type summariesWithNewestRequestsFirst []Summary
+
+// Interface methods for sorting review summaries in reverse chronological order
+func (summaries summariesWithNewestRequestsFirst) Len() int { return len(summaries) }
+func (summaries summariesWithNewestRequestsFirst) Swap(i, j int) {
+	summaries[i], summaries[j] = summaries[j], summaries[i]
+}
+func (summaries summariesWithNewestRequestsFirst) Less(i, j int) bool {
+	return summaries[i].Request.Timestamp > summaries[j].Request.Timestamp
+}
+
+// updateThreadsStatus calculates the aggregate status of a sequence of comment threads.
+//
+// The aggregate status is the conjunction of all of the non-nil child statuses.
+//
+// This has the side-effect of setting the "Resolved" field of all descendant comment threads.
+func updateThreadsStatus(threads []CommentThread) *bool {
+	sort.Stable(byTimestamp(threads))
+	noUnresolved := true
+	var result *bool
+	for i := range threads {
+		thread := &threads[i]
+		thread.updateResolvedStatus()
+		if thread.Resolved != nil {
+			noUnresolved = noUnresolved && *thread.Resolved
+			result = &noUnresolved
+		}
+	}
+	return result
+}
+
+// updateResolvedStatus calculates the aggregate status of a single comment thread,
+// and updates the "Resolved" field of that thread accordingly.
+func (thread *CommentThread) updateResolvedStatus() {
+	resolved := updateThreadsStatus(thread.Children)
+	if resolved == nil {
+		thread.Resolved = thread.Comment.Resolved
+		return
+	}
+
+	if !*resolved {
+		thread.Resolved = resolved
+		return
+	}
+
+	if thread.Comment.Resolved == nil || !*thread.Comment.Resolved {
+		thread.Resolved = nil
+		return
+	}
+
+	thread.Resolved = resolved
+}
+
+// mutableThread is an internal-only data structure used to store partially constructed comment threads.
+type mutableThread struct {
+	Hash     string
+	Comment  comment.Comment
+	Children []*mutableThread
+}
+
+// fixMutableThread is a helper method to finalize a mutableThread struct
+// (partially constructed comment thread) as a CommentThread struct
+// (fully constructed comment thread).
+func fixMutableThread(mutableThread *mutableThread) CommentThread {
+	var children []CommentThread
+	for _, mutableChild := range mutableThread.Children {
+		children = append(children, fixMutableThread(mutableChild))
+	}
+	return CommentThread{
+		Hash:     mutableThread.Hash,
+		Comment:  mutableThread.Comment,
+		Children: children,
+	}
+}
+
+// This function builds the comment thread tree from the log-based list of comments.
+//
+// Since the comments can be processed in any order, this uses an internal mutable
+// data structure, and then converts it to the proper CommentThread structure at the end.
+func buildCommentThreads(commentsByHash map[string]comment.Comment) []CommentThread {
+	threadsByHash := make(map[string]*mutableThread)
+	for hash, comment := range commentsByHash {
+		thread, ok := threadsByHash[hash]
+		if !ok {
+			thread = &mutableThread{
+				Hash:    hash,
+				Comment: comment,
+			}
+			threadsByHash[hash] = thread
+		}
+	}
+	var rootHashes []string
+	for hash, thread := range threadsByHash {
+		if thread.Comment.Parent == "" {
+			rootHashes = append(rootHashes, hash)
+		} else {
+			parent, ok := threadsByHash[thread.Comment.Parent]
+			if ok {
+				parent.Children = append(parent.Children, thread)
+			}
+		}
+	}
+	var threads []CommentThread
+	for _, hash := range rootHashes {
+		threads = append(threads, fixMutableThread(threadsByHash[hash]))
+	}
+	return threads
+}
+
+// loadComments reads in the log-structured sequence of comments for a review,
+// and then builds the corresponding tree-structured comment threads.
+func (r *Summary) loadComments(commentNotes []repository.Note) []CommentThread {
+	commentsByHash := comment.ParseAllValid(commentNotes)
+	return buildCommentThreads(commentsByHash)
+}
+
+func getSummaryFromNotes(repo repository.Repo, revision string, requestNotes, commentNotes []repository.Note) (*Summary, error) {
+	requests := request.ParseAllValid(requestNotes)
+	if requests == nil {
+		return nil, nil
+	}
+	sort.Stable(requestsByTimestamp(requests))
+	reviewSummary := Summary{
+		Repo:        repo,
+		Revision:    revision,
+		Request:     requests[len(requests)-1],
+		AllRequests: requests,
+	}
+	reviewSummary.Comments = reviewSummary.loadComments(commentNotes)
+	reviewSummary.Resolved = updateThreadsStatus(reviewSummary.Comments)
+	return &reviewSummary, nil
+}
+
+// GetSummary returns the summary of the specified code review.
+//
+// If no review request exists, the returned review summary is nil.
+func GetSummary(repo repository.Repo, revision string) (*Summary, error) {
+	requestNotes := repo.GetNotes(request.Ref, revision)
+	commentNotes := repo.GetNotes(comment.Ref, revision)
+	summary, err := getSummaryFromNotes(repo, revision, requestNotes, commentNotes)
+	if err != nil {
+		return nil, err
+	}
+	currentCommit := revision
+	if summary.Request.Alias != "" {
+		currentCommit = summary.Request.Alias
+	}
+	submitted, err := repo.IsAncestor(currentCommit, summary.Request.TargetRef)
+	if err != nil {
+		return nil, err
+	}
+	summary.Submitted = submitted
+	return summary, nil
+}
+
+// Details returns the detailed review for the given summary.
+func (r *Summary) Details() (*Review, error) {
+	review := Review{
+		Summary: r,
+	}
+	currentCommit, err := review.GetHeadCommit()
+	if err == nil {
+		review.Reports = ci.ParseAllValid(review.Repo.GetNotes(ci.Ref, currentCommit))
+		review.Analyses = analyses.ParseAllValid(review.Repo.GetNotes(analyses.Ref, currentCommit))
+	}
+	return &review, nil
+}
+
+// Get returns the specified code review.
+//
+// If no review request exists, the returned review is nil.
+func Get(repo repository.Repo, revision string) (*Review, error) {
+	summary, err := GetSummary(repo, revision)
+	if err != nil {
+		return nil, err
+	}
+	if summary == nil {
+		return nil, nil
+	}
+	return summary.Details()
+}
+
+func getIsSubmittedCheck(repo repository.Repo) func(ref, commit string) bool {
+	refCommitsMap := make(map[string]map[string]bool)
+
+	getRefCommitsMap := func(ref string) map[string]bool {
+		commitsMap, ok := refCommitsMap[ref]
+		if ok {
+			return commitsMap
+		}
+		commitsMap = make(map[string]bool)
+		for _, commit := range repo.ListCommits(ref) {
+			commitsMap[commit] = true
+		}
+		refCommitsMap[ref] = commitsMap
+		return commitsMap
+	}
+
+	return func(ref, commit string) bool {
+		return getRefCommitsMap(ref)[commit]
+	}
+}
+
+func unsortedListAll(repo repository.Repo) []Summary {
+	reviewNotesMap, err := repo.GetAllNotes(request.Ref)
+	if err != nil {
+		return nil
+	}
+	discussNotesMap, err := repo.GetAllNotes(comment.Ref)
+	if err != nil {
+		return nil
+	}
+
+	isSubmittedCheck := getIsSubmittedCheck(repo)
+	var reviews []Summary
+	for commit, notes := range reviewNotesMap {
+		summary, err := getSummaryFromNotes(repo, commit, notes, discussNotesMap[commit])
+		if err != nil {
+			continue
+		}
+		summary.Submitted = isSubmittedCheck(summary.Request.TargetRef, summary.getStartingCommit())
+		reviews = append(reviews, *summary)
+	}
+	return reviews
+}
+
+// ListAll returns all reviews stored in the git-notes.
+func ListAll(repo repository.Repo) []Summary {
+	reviews := unsortedListAll(repo)
+	sort.Stable(summariesWithNewestRequestsFirst(reviews))
+	return reviews
+}
+
+// ListOpen returns all reviews that are not yet incorporated into their target refs.
+func ListOpen(repo repository.Repo) []Summary {
+	var openReviews []Summary
+	for _, review := range unsortedListAll(repo) {
+		if !review.Submitted {
+			openReviews = append(openReviews, review)
+		}
+	}
+	sort.Stable(summariesWithNewestRequestsFirst(openReviews))
+	return openReviews
+}
+
+// GetCurrent returns the current, open code review.
+//
+// If there are multiple matching reviews, then an error is returned.
+func GetCurrent(repo repository.Repo) (*Review, error) {
+	reviewRef, err := repo.GetHeadRef()
+	if err != nil {
+		return nil, err
+	}
+	var matchingReviews []Summary
+	for _, review := range ListOpen(repo) {
+		if review.Request.ReviewRef == reviewRef {
+			matchingReviews = append(matchingReviews, review)
+		}
+	}
+	if matchingReviews == nil {
+		return nil, nil
+	}
+	if len(matchingReviews) != 1 {
+		return nil, fmt.Errorf("There are %d open reviews for the ref \"%s\"", len(matchingReviews), reviewRef)
+	}
+	return matchingReviews[0].Details()
+}
+
+// GetBuildStatusMessage returns a string of the current build-and-test status
+// of the review, or "unknown" if the build-and-test status cannot be determined.
+func (r *Review) GetBuildStatusMessage() string {
+	statusMessage := "unknown"
+	ciReport, err := ci.GetLatestCIReport(r.Reports)
+	if err != nil {
+		return fmt.Sprintf("unknown: %s", err)
+	}
+	if ciReport != nil {
+		statusMessage = fmt.Sprintf("%s (%q)", ciReport.Status, ciReport.URL)
+	}
+	return statusMessage
+}
+
+// GetAnalysesNotes returns all of the notes from the most recent static
+// analysis run recorded in the git notes.
+func (r *Review) GetAnalysesNotes() ([]analyses.Note, error) {
+	latestAnalyses, err := analyses.GetLatestAnalysesReport(r.Analyses)
+	if err != nil {
+		return nil, err
+	}
+	if latestAnalyses == nil {
+		return nil, fmt.Errorf("No analyses available")
+	}
+	return latestAnalyses.GetNotes()
+}
+
+// GetAnalysesMessage returns a string summarizing the results of the
+// most recent static analyses.
+func (r *Review) GetAnalysesMessage() string {
+	latestAnalyses, err := analyses.GetLatestAnalysesReport(r.Analyses)
+	if err != nil {
+		return err.Error()
+	}
+	if latestAnalyses == nil {
+		return "No analyses available"
+	}
+	status := latestAnalyses.Status
+	if status != "" && status != analyses.StatusNeedsMoreWork {
+		return status
+	}
+	analysesNotes, err := latestAnalyses.GetNotes()
+	if err != nil {
+		return err.Error()
+	}
+	if analysesNotes == nil {
+		return "passed"
+	}
+	return fmt.Sprintf("%d warnings\n", len(analysesNotes))
+	// TODO(ojarjur): Figure out the best place to display the actual notes
+}
+
+func prettyPrintJSON(jsonBytes []byte) (string, error) {
+	var prettyBytes bytes.Buffer
+	err := json.Indent(&prettyBytes, jsonBytes, "", "  ")
+	if err != nil {
+		return "", err
+	}
+	return prettyBytes.String(), nil
+}
+
+// GetJSON returns the pretty printed JSON for a review summary.
+func (r *Summary) GetJSON() (string, error) {
+	jsonBytes, err := json.Marshal(*r)
+	if err != nil {
+		return "", err
+	}
+	return prettyPrintJSON(jsonBytes)
+}
+
+// GetJSON returns the pretty printed JSON for a review.
+func (r *Review) GetJSON() (string, error) {
+	jsonBytes, err := json.Marshal(*r)
+	if err != nil {
+		return "", err
+	}
+	return prettyPrintJSON(jsonBytes)
+}
+
+// findLastCommit returns the later (newest) commit from the union of the provided commit
+// and all of the commits that are referenced in the given comment threads.
+func (r *Review) findLastCommit(startingCommit, latestCommit string, commentThreads []CommentThread) string {
+	isLater := func(commit string) bool {
+		if err := r.Repo.VerifyCommit(commit); err != nil {
+			return false
+		}
+		if t, e := r.Repo.IsAncestor(latestCommit, commit); e == nil && t {
+			return true
+		}
+		if t, e := r.Repo.IsAncestor(startingCommit, commit); e == nil && !t {
+			return false
+		}
+		if t, e := r.Repo.IsAncestor(commit, latestCommit); e == nil && t {
+			return false
+		}
+		ct, err := r.Repo.GetCommitTime(commit)
+		if err != nil {
+			return false
+		}
+		lt, err := r.Repo.GetCommitTime(latestCommit)
+		if err != nil {
+			return true
+		}
+		return ct > lt
+	}
+	updateLatest := func(commit string) {
+		if commit == "" {
+			return
+		}
+		if isLater(commit) {
+			latestCommit = commit
+		}
+	}
+	for _, commentThread := range commentThreads {
+		comment := commentThread.Comment
+		if comment.Location != nil {
+			updateLatest(comment.Location.Commit)
+		}
+		updateLatest(r.findLastCommit(startingCommit, latestCommit, commentThread.Children))
+	}
+	return latestCommit
+}
+
+func (r *Summary) getStartingCommit() string {
+	if r.Request.Alias != "" {
+		return r.Request.Alias
+	}
+	return r.Revision
+}
+
+// GetHeadCommit returns the latest commit in a review.
+func (r *Review) GetHeadCommit() (string, error) {
+	currentCommit := r.getStartingCommit()
+	if r.Request.ReviewRef == "" {
+		return currentCommit, nil
+	}
+
+	if r.Submitted {
+		// The review has already been submitted.
+		// Go through the list of comments and find the last commented upon commit.
+		return r.findLastCommit(currentCommit, currentCommit, r.Comments), nil
+	}
+
+	// It is possible that the review ref is no longer an ancestor of the starting
+	// commit (e.g. if a rebase left us in a detached head), in which case we have to
+	// find the head commit without using it.
+	useReviewRef, err := r.Repo.IsAncestor(currentCommit, r.Request.ReviewRef)
+	if err != nil {
+		return "", err
+	}
+	if useReviewRef {
+		return r.Repo.ResolveRefCommit(r.Request.ReviewRef)
+	}
+
+	return r.findLastCommit(currentCommit, currentCommit, r.Comments), nil
+}
+
+// GetBaseCommit returns the commit against which a review should be compared.
+func (r *Review) GetBaseCommit() (string, error) {
+	if r.Submitted {
+		if r.Request.BaseCommit != "" {
+			return r.Request.BaseCommit, nil
+		}
+
+		// This means the review has been submitted, but did not specify a base commit.
+		// In this case, we have to treat the last parent commit as the base. This is
+		// usually what we want, since merging a target branch into a feature branch
+		// results in the previous commit to the feature branch being the first parent,
+		// and the latest commit to the target branch being the second parent.
+		return r.Repo.GetLastParent(r.Revision)
+	}
+
+	targetRefHead, err := r.Repo.ResolveRefCommit(r.Request.TargetRef)
+	if err != nil {
+		return "", err
+	}
+	leftHandSide := targetRefHead
+	rightHandSide := r.Revision
+	if r.Request.ReviewRef != "" {
+		if reviewRefHead, err := r.Repo.ResolveRefCommit(r.Request.ReviewRef); err == nil {
+			rightHandSide = reviewRefHead
+		}
+	}
+
+	return r.Repo.MergeBase(leftHandSide, rightHandSide)
+}
+
+// GetDiff returns the diff for a review.
+func (r *Review) GetDiff(diffArgs ...string) (string, error) {
+	var baseCommit, headCommit string
+	baseCommit, err := r.GetBaseCommit()
+	if err == nil {
+		headCommit, err = r.GetHeadCommit()
+	}
+	if err == nil {
+		return r.Repo.Diff(baseCommit, headCommit, diffArgs...)
+	}
+	return "", err
+}
+
+// AddComment adds the given comment to the review.
+func (r *Review) AddComment(c comment.Comment) error {
+	commentNote, err := c.Write()
+	if err != nil {
+		return err
+	}
+
+	r.Repo.AppendNote(comment.Ref, r.Revision, commentNote)
+	return nil
+}
+
+// Rebase performs an interactive rebase of the review onto its target ref.
+//
+// If the 'archivePrevious' argument is true, then the previous head of the
+// review will be added to the 'refs/devtools/archives/reviews' ref prior
+// to being rewritten. That ensures the review history is kept from being
+// garbage collected.
+func (r *Review) Rebase(archivePrevious bool) error {
+	if archivePrevious {
+		orig, err := r.GetHeadCommit()
+		if err != nil {
+			return err
+		}
+		if err := r.Repo.ArchiveRef(orig, archiveRef); err != nil {
+			return err
+		}
+	}
+	if err := r.Repo.SwitchToRef(r.Request.ReviewRef); err != nil {
+		return err
+	}
+	if err := r.Repo.RebaseRef(r.Request.TargetRef); err != nil {
+		return err
+	}
+	alias, err := r.Repo.GetCommitHash("HEAD")
+	if err != nil {
+		return err
+	}
+	r.Request.Alias = alias
+	newNote, err := r.Request.Write()
+	if err != nil {
+		return err
+	}
+	return r.Repo.AppendNote(request.Ref, r.Revision, newNote)
+}
diff --git a/vendor/vendor.json b/vendor/vendor.json
index b0ee83b0151d5..c208e3bb6350b 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -272,6 +272,42 @@
 			"revision": "5f1c01d9f64b941dd9582c638279d046eda6ca31",
 			"revisionTime": "2016-03-04T05:48:22Z"
 		},
+		{
+			"checksumSHA1": "IITmVQEfzVueGJGQJxPFAdt6t2w=",
+			"path": "github.com/google/git-appraise/repository",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
+		{
+			"checksumSHA1": "2LErsrVeFNuWrKRQJ/570SqrsQE=",
+			"path": "github.com/google/git-appraise/review",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
+		{
+			"checksumSHA1": "SZAJqeovAchS/gu5YHd2piRHD44=",
+			"path": "github.com/google/git-appraise/review/analyses",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
+		{
+			"checksumSHA1": "3JRKevH7OBnaUJHY8xHujdySCzo=",
+			"path": "github.com/google/git-appraise/review/ci",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
+		{
+			"checksumSHA1": "KXCHXZ8KrnNt08H32JaK6Ujrjwg=",
+			"path": "github.com/google/git-appraise/review/comment",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
+		{
+			"checksumSHA1": "cI6UctsmwxeoAEHTFH5oAfoh1tM=",
+			"path": "github.com/google/git-appraise/review/request",
+			"revision": "4a3502c80637eab79d6cb699a550abe9b6a1c158",
+			"revisionTime": "2016-09-21T00:24:38Z"
+		},
 		{
 			"checksumSHA1": "P3zGmsNjW8m15a+nks4FdVpFKwE=",
 			"path": "github.com/gopherjs/gopherjs/js",