Support displaying diff stats in PR tab bar

routers/web/repo/pull.go

@@ -357,6 +357,72 @@ func setMergeTarget(ctx *context.Context, pull *issues_model.PullRequest) {
 	ctx.Data["BaseBranchLink"] = pull.GetBaseBranchLink()
 }
 
+// GetPullDiffStats get Pull Requests diff stats
+func GetPullDiffStats(ctx *context.Context) {
+	issue := checkPullInfo(ctx)
+	pull := issue.PullRequest
+
+	var (
+		startCommitID string
+		endCommitID   string
+		gitRepo       = ctx.Repo.GitRepo
+	)
+
+	var prInfo *git.CompareInfo
+
+	if pull.HasMerged {
+		prInfo = PrepareMergedViewPullInfo(ctx, issue)
+	} else {
+		prInfo = PrepareViewPullInfo(ctx, issue)
+	}
+
+	if ctx.Written() {
+		return
+	} else if prInfo == nil {
+		ctx.NotFound("PullFiles", nil)
+		return
+	}
+
+	headCommitID, err := gitRepo.GetRefCommitID(pull.GetGitRefName())
+	if err != nil {
+		ctx.ServerError("GetRefCommitID", err)
+		return
+	}
+
+	startCommitID = prInfo.MergeBase
+	endCommitID = headCommitID
+
+	fileOnly := ctx.FormBool("file-only")
+
+	maxLines, maxFiles := setting.Git.MaxGitDiffLines, setting.Git.MaxGitDiffFiles
+	files := ctx.FormStrings("files")
+	if fileOnly && (len(files) == 2 || len(files) == 1) {
+		maxLines, maxFiles = -1, -1
+	}
+	diffOptions := &gitdiff.DiffOptions{
+		BeforeCommitID:     startCommitID,
+		AfterCommitID:      endCommitID,
+		SkipTo:             ctx.FormString("skip-to"),
+		MaxLines:           maxLines,
+		MaxLineCharacters:  setting.Git.MaxGitDiffLineCharacters,
+		MaxFiles:           maxFiles,
+		WhitespaceBehavior: gitdiff.GetWhitespaceFlag(ctx.Data["WhitespaceBehavior"].(string)),
+	}
+
+	var methodWithError string
+	var diff *gitdiff.Diff
+
+	diff, err = gitdiff.GetDiff(gitRepo, diffOptions, files...)
+	methodWithError = "GetDiff"
+
+	if err != nil {
+		ctx.ServerError(methodWithError, err)
+		return
+	}
+
+	ctx.Data["Diff"] = diff
+}
+
 // PrepareMergedViewPullInfo show meta information for a merged pull request view page
 func PrepareMergedViewPullInfo(ctx *context.Context, issue *issues_model.Issue) *git.CompareInfo {
 	pull := issue.PullRequest

routers/web/web.go

@@ -1263,9 +1263,10 @@ func registerRoutes(m *web.Route) {
 		})
 
 		m.Group("/pulls/{index}", func() {
+			m.Get("", repo.SetWhitespaceBehavior, repo.GetPullDiffStats, repo.ViewIssue)
 			m.Get(".diff", repo.DownloadPullDiff)
 			m.Get(".patch", repo.DownloadPullPatch)
-			m.Get("/commits", context.RepoRef(), repo.ViewPullCommits)
+			m.Get("/commits", context.RepoRef(), repo.SetWhitespaceBehavior, repo.GetPullDiffStats, repo.ViewPullCommits)
 			m.Post("/merge", context.RepoMustNotBeArchived(), web.Bind(forms.MergePullRequestForm{}), repo.MergePullRequest)
 			m.Post("/cancel_auto_merge", context.RepoMustNotBeArchived(), repo.CancelAutoMergePullRequest)
 			m.Post("/update", repo.UpdatePullRequest)

templates/repo/pulls/tab_menu.tmpl

@@ -14,4 +14,10 @@
 		{{$.locale.Tr "repo.pulls.tab_files"}}
 		<span class="ui small label">{{if .NumFiles}}{{.NumFiles}}{{else}}-{{end}}</span>
 	</a>
+	<span class="item gt-ml-auto gt-pr-0 gt-font-bold gt-df gt-ac gt-gap-3">
+		<span><span class="text green">+{{if .Diff.TotalAddition}}{{.Diff.TotalAddition}}{{else}}0{{end}}</span> <span class="text red">-{{if .Diff.TotalDeletion}}{{.Diff.TotalDeletion}}{{else}}0{{end}}</span></span>
+		<span class="diff-stats-bar">
+			<div class="diff-stats-add-bar" style="width: 50%;"></div>
+		</span>
+	</span>
 </div>