From 54b535a527c24c64a97127b66c39b57a0e363f3a Mon Sep 17 00:00:00 2001
From: 6543 <6543@obermui.de>
Date: Tue, 25 Oct 2022 06:38:39 +0800
Subject: [PATCH] Find DefaultPRHead based on branch and SHA (#514)

Reviewed-on: https://gitea.com/gitea/tea/pulls/514
Reviewed-by: strk <strk@noreply.gitea.io>
Reviewed-by: Norwin <noerw@noreply.gitea.io>
---
 modules/git/branch.go       | 51 +++++++++++++++++++++++++++----------
 modules/task/pull_create.go |  5 ++--
 2 files changed, 40 insertions(+), 16 deletions(-)

diff --git a/modules/git/branch.go b/modules/git/branch.go
index 6fef68d..f39c837 100644
--- a/modules/git/branch.go
+++ b/modules/git/branch.go
@@ -173,6 +173,7 @@ func (r TeaRepo) TeaFindBranchByName(branchName, repoURL string) (b *git_config.
 // 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.
+// Priority order is: first match of sha and branch -> first match of branch -> first match of sha
 func (r TeaRepo) TeaFindBranchRemote(branchName, hash string) (*git.Remote, error) {
 	remotes, err := r.Remotes()
 	if err != nil {
@@ -193,35 +194,57 @@ func (r TeaRepo) TeaFindBranchRemote(branchName, hash string) (*git.Remote, erro
 	}
 	defer iter.Close()
 
-	var match *git.Remote
-	err = iter.ForEach(func(ref *git_plumbing.Reference) error {
+	var shaMatch *git.Remote
+	var branchMatch *git.Remote
+	var fullMatch *git.Remote
+	if 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
+			if branchMatch == nil && branchName != "" && branchName == branch {
+				if branchMatch, err = r.Remote(remote); err != nil {
+					return err
+				}
+			}
+			if shaMatch == nil && hash != "" && hash == ref.Hash().String() {
+				if shaMatch, err = r.Remote(remote); err != nil {
+					return err
+				}
+			}
+			if fullMatch == nil && branchName != "" && branchName == branch && hash != "" && hash == ref.Hash().String() {
+				if fullMatch, err = r.Remote(remote); err != nil {
+					return err
+				}
+				// stop asap you have a full match
+				return nil
 			}
 		}
 		return nil
-	})
+	}); err != nil {
+		return nil, err
+	}
 
-	return match, err
+	if fullMatch != nil {
+		return fullMatch, nil
+	} else if branchMatch != nil {
+		return branchMatch, nil
+	} else if shaMatch != nil {
+		return shaMatch, nil
+	}
+	return nil, nil
 }
 
-// TeaGetCurrentBranchName return the name of the branch witch is currently active
-func (r TeaRepo) TeaGetCurrentBranchName() (string, error) {
+// TeaGetCurrentBranchNameAndSHA return the name and sha of the branch witch is currently active
+func (r TeaRepo) TeaGetCurrentBranchNameAndSHA() (string, string, error) {
 	localHead, err := r.Head()
 	if err != nil {
-		return "", err
+		return "", "", err
 	}
 
 	if !localHead.Name().IsBranch() {
-		return "", fmt.Errorf("active ref is no branch")
+		return "", "", fmt.Errorf("active ref is no branch")
 	}
 
-	return localHead.Name().Short(), nil
+	return localHead.Name().Short(), localHead.Hash().String(), nil
 }
diff --git a/modules/task/pull_create.go b/modules/task/pull_create.go
index 736fe63..f61108e 100644
--- a/modules/task/pull_create.go
+++ b/modules/task/pull_create.go
@@ -99,11 +99,12 @@ func GetDefaultPRBase(login *config.Login, owner, repo string) (string, error) {
 // that has a branch with the same name, and extracts the owner from its URL.
 // If no remote matches, owner is empty, meaning same as head repo owner.
 func GetDefaultPRHead(localRepo *local_git.TeaRepo) (owner, branch string, err error) {
-	if branch, err = localRepo.TeaGetCurrentBranchName(); err != nil {
+	var sha string
+	if branch, sha, err = localRepo.TeaGetCurrentBranchNameAndSHA(); err != nil {
 		return
 	}
 
-	remote, err := localRepo.TeaFindBranchRemote(branch, "")
+	remote, err := localRepo.TeaFindBranchRemote(branch, sha)
 	if err != nil {
 		err = fmt.Errorf("could not determine remote for current branch: %s", err)
 		return