Put an edit file button on pull request files to allow a quick operation (#29697)

Resolve #23848

This PR put an edit file button on pull request files to allow a quick
edit for a file. After the edit finished, it will return back to the
viewed file position on pull request files tab.

It also use a branch view file link instead of commit link when it's a
non-commit pull request files view.

<img width="1532" alt="image"
src="https://github.com/go-gitea/gitea/assets/81045/3637ca4c-89d5-4621-847b-79702a44f617">

---------

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>

2 files changed, 36 insertions, 2 deletions

diff --git a/routers/web/repo/editor.go b/routers/web/repo/editor.go
index 082666276a..474f7ff1da 100644
--- a/routers/web/repo/editor.go
+++ b/routers/web/repo/editor.go
@@ -80,8 +80,12 @@ func redirectForCommitChoice(ctx *context.Context, commitChoice, newBranchName,
 		}
 	}
 
-	// Redirect to viewing file or folder
-	ctx.Redirect(ctx.Repo.RepoLink + "/src/branch/" + util.PathEscapeSegments(newBranchName) + "/" + util.PathEscapeSegments(treePath))
+	returnURI := ctx.FormString("return_uri")
+
+	ctx.RedirectToCurrentSite(
+		returnURI,
+		ctx.Repo.RepoLink+"/src/branch/"+util.PathEscapeSegments(newBranchName)+"/"+util.PathEscapeSegments(treePath),
+	)
 }
 
 // getParentTreeFields returns list of parent tree names and corresponding tree paths
@@ -100,6 +104,7 @@ func getParentTreeFields(treePath string) (treeNames, treePaths []string) {
 }
 
 func editFile(ctx *context.Context, isNewFile bool) {
+	ctx.Data["PageIsViewCode"] = true
 	ctx.Data["PageIsEdit"] = true
 	ctx.Data["IsNewFile"] = isNewFile
 	canCommit := renderCommitRights(ctx)
@@ -190,6 +195,9 @@ func editFile(ctx *context.Context, isNewFile bool) {
 	ctx.Data["LineWrapExtensions"] = strings.Join(setting.Repository.Editor.LineWrapExtensions, ",")
 	ctx.Data["EditorconfigJson"] = GetEditorConfig(ctx, treePath)
 
+	ctx.Data["IsEditingFileOnly"] = ctx.FormString("return_uri") != ""
+	ctx.Data["ReturnURI"] = ctx.FormString("return_uri")
+
 	ctx.HTML(http.StatusOK, tplEditFile)
 }
 
diff --git a/routers/web/repo/pull.go b/routers/web/repo/pull.go
index 2422be39b8..a0a8e5410c 100644
--- a/routers/web/repo/pull.go
+++ b/routers/web/repo/pull.go
@@ -857,6 +857,32 @@ func viewPullFiles(ctx *context.Context, specifiedStartCommit, specifiedEndCommi
 	ctx.Data["CanBlockUser"] = func(blocker, blockee *user_model.User) bool {
 		return user_service.CanBlockUser(ctx, ctx.Doer, blocker, blockee)
 	}
+	if !willShowSpecifiedCommit && !willShowSpecifiedCommitRange && pull.Flow == issues_model.PullRequestFlowGithub {
+		if err := pull.LoadHeadRepo(ctx); err != nil {
+			ctx.ServerError("LoadHeadRepo", err)
+			return
+		}
+
+		if pull.HeadRepo != nil {
+			ctx.Data["SourcePath"] = pull.HeadRepo.Link() + "/src/branch/" + util.PathEscapeSegments(pull.HeadBranch)
+		}
+
+		if !pull.HasMerged && ctx.Doer != nil {
+			perm, err := access_model.GetUserRepoPermission(ctx, pull.HeadRepo, ctx.Doer)
+			if err != nil {
+				ctx.ServerError("GetUserRepoPermission", err)
+				return
+			}
+
+			if perm.CanWrite(unit.TypeCode) || issues_model.CanMaintainerWriteToBranch(ctx, perm, pull.HeadBranch, ctx.Doer) {
+				ctx.Data["CanEditFile"] = true
+				ctx.Data["EditFileTooltip"] = ctx.Tr("repo.editor.edit_this_file")
+				ctx.Data["HeadRepoLink"] = pull.HeadRepo.Link()
+				ctx.Data["HeadBranchName"] = pull.HeadBranch
+				ctx.Data["BackToLink"] = setting.AppSubURL + ctx.Req.URL.RequestURI()
+			}
+		}
+	}
 
 	ctx.HTML(http.StatusOK, tplPullFiles)
 }