From 159bf03d491df468e810701fd00d320fee5d8792 Mon Sep 17 00:00:00 2001
From: Norwin <noerw@noreply.gitea.io>
Date: Thu, 24 Sep 2020 10:44:03 +0000
Subject: [PATCH] tea pulls create: detect head branch repo owner (#193)

dont print on already pushed branch

more consisten error handling

detect repo owner for default head branch

Co-authored-by: Norwin Roosen <git@nroo.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/193
Reviewed-by: 6543 <6543@noreply.gitea.io>
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
---
 cmd/pulls.go          | 46 +++++++++++++++++++++++++++++++++----------
 modules/git/branch.go | 42 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+), 10 deletions(-)

diff --git a/cmd/pulls.go b/cmd/pulls.go
index c9afcb4..f10954f 100644
--- a/cmd/pulls.go
+++ b/cmd/pulls.go
@@ -341,13 +341,20 @@ func runPullsCreate(ctx *cli.Context) error {
 
 	repo, _, err := login.Client().GetRepo(ownerArg, repoArg)
 	if err != nil {
-		log.Fatal(err)
+		log.Fatal("could not fetch repo meta: ", err)
 	}
 
 	// open local git repo
 	localRepo, err := local_git.RepoForWorkdir()
 	if err != nil {
-		log.Fatal(err)
+		log.Fatal("could not open local repo: ", err)
+	}
+
+	// push if possible
+	log.Println("git push")
+	err = localRepo.Push(&git.PushOptions{})
+	if err != nil && err != git.NoErrAlreadyUpToDate {
+		log.Printf("Error occurred during 'git push':\n%s\n", err.Error())
 	}
 
 	base := ctx.String("base")
@@ -359,10 +366,35 @@ func runPullsCreate(ctx *cli.Context) error {
 	head := ctx.String("head")
 	// default is current one
 	if len(head) == 0 {
-		head, err = localRepo.TeaGetCurrentBranchName()
+		headBranch, err := localRepo.Head()
 		if err != nil {
 			log.Fatal(err)
 		}
+		sha := headBranch.Hash().String()
+
+		remote, err := localRepo.TeaFindBranchRemote("", sha)
+		if err != nil {
+			return err
+		}
+
+		if remote == nil {
+			// if no remote branch is found for the local hash, we abort:
+			// user has probably not configured a remote for the local branch,
+			// or local branch does not represent remote state.
+			log.Fatal("no matching remote found for this branch. try git push -u <remote> <branch>")
+		}
+
+		branchName, err := localRepo.TeaGetCurrentBranchName()
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		url, err := local_git.ParseURL(remote.Config().URLs[0])
+		if err != nil {
+			log.Fatal(err)
+		}
+		owner, _ := getOwnerAndRepo(strings.TrimLeft(url.Path, "/"), "")
+		head = fmt.Sprintf("%s:%s", owner, branchName)
 	}
 
 	title := ctx.String("title")
@@ -382,12 +414,6 @@ func runPullsCreate(ctx *cli.Context) error {
 		return nil
 	}
 
-	// push if possible
-	err = localRepo.Push(&git.PushOptions{})
-	if err != nil {
-		fmt.Printf("Error occurred during 'git push':\n%s\n", err.Error())
-	}
-
 	pr, _, err := client.CreatePullRequest(ownerArg, repoArg, gitea.CreatePullRequestOption{
 		Head:  head,
 		Base:  base,
@@ -396,7 +422,7 @@ func runPullsCreate(ctx *cli.Context) error {
 	})
 
 	if err != nil {
-		log.Fatal(err)
+		log.Fatal("could not create PR: ", err)
 	}
 
 	in := fmt.Sprintf("# #%d %s (%s)\n%s created %s\n\n%s\n", pr.Index,
diff --git a/modules/git/branch.go b/modules/git/branch.go
index 8732cd3..042a18b 100644
--- a/modules/git/branch.go
+++ b/modules/git/branch.go
@@ -176,6 +176,48 @@ func (r TeaRepo) TeaFindBranchByName(branchName, repoURL string) (b *git_config.
 	return b, b.Validate()
 }
 
+// TeaFindBranchRemote gives the first remote that has a branch with the same name or sha,
+// depending on what is passed in.
+// This function is needed, as git does not always define branches in .git/config with remote entries.
+func (r TeaRepo) TeaFindBranchRemote(branchName, hash string) (*git.Remote, error) {
+	remotes, err := r.Remotes()
+	if err != nil {
+		return nil, err
+	}
+
+	switch {
+	case len(remotes) == 0:
+		return nil, nil
+	case len(remotes) == 1:
+		return remotes[0], nil
+	}
+
+	// check if the given remote has our branch (.git/refs/remotes/<remoteName>/*)
+	iter, err := r.References()
+	if err != nil {
+		return nil, err
+	}
+	defer iter.Close()
+
+	var match *git.Remote
+	err = iter.ForEach(func(ref *git_plumbing.Reference) error {
+		if ref.Name().IsRemote() {
+			names := strings.SplitN(ref.Name().Short(), "/", 2)
+			remote := names[0]
+			branch := names[1]
+			hashMatch := hash != "" && hash == ref.Hash().String()
+			nameMatch := branchName != "" && branchName == branch
+			if hashMatch || nameMatch {
+				match, err = r.Remote(remote)
+				return err
+			}
+		}
+		return nil
+	})
+
+	return match, err
+}
+
 // TeaGetCurrentBranchName return the name of the branch witch is currently active
 func (r TeaRepo) TeaGetCurrentBranchName() (string, error) {
 	localHead, err := r.Head()