From 9bee0d8840b557f8e4696aeeb6ec0feb061d7b0c Mon Sep 17 00:00:00 2001
From: Frederick Zhang <frederick888@tsundere.moe>
Date: Fri, 14 Jun 2024 14:43:38 +1000
Subject: [PATCH] Find PRs using @{push}

When using a triangular workflow with push.default = current and
upstream being set to the target branch [1], or a similar but simpler
central workflow [2], we should use @{push} instead to locate the remote
branch.

In fact, @{push} covers most cases in push.default = upstream too. The
branch.<name>.merge is probably only needed when using RemoteURL and
different remote / local branch names.

[1] https://github.com/cli/cli/issues/575#issuecomment-706853545
[2] https://github.com/tpope/vim-fugitive/issues/1172#issuecomment-522301607
---
 git/client.go                    |  3 +++
 git/objects.go                   |  1 +
 pkg/cmd/pr/shared/finder.go      |  4 +++-
 pkg/cmd/pr/shared/finder_test.go | 10 ++++++++++
 pkg/cmd/pr/status/status.go      |  4 +++-
 5 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/git/client.go b/git/client.go
index b0194affc43..b68ca22373a 100644
--- a/git/client.go
+++ b/git/client.go
@@ -355,6 +355,9 @@ func (c *Client) ReadBranchConfig(ctx context.Context, branch string) (cfg Branc
 			cfg.MergeRef = parts[1]
 		}
 	}
+	if out, err = c.revParse(ctx, "--verify", "--quiet", "--abbrev-ref", branch+"@{push}"); err == nil {
+		cfg.Push = strings.TrimSuffix(string(out), "\n")
+	}
 	return
 }
 
diff --git a/git/objects.go b/git/objects.go
index c33d92b7cb2..138584fccf0 100644
--- a/git/objects.go
+++ b/git/objects.go
@@ -74,4 +74,5 @@ type BranchConfig struct {
 	RemoteName string
 	RemoteURL  *url.URL
 	MergeRef   string
+	Push       string
 }
diff --git a/pkg/cmd/pr/shared/finder.go b/pkg/cmd/pr/shared/finder.go
index 4bb79ac8b64..f28cc2aaaf2 100644
--- a/pkg/cmd/pr/shared/finder.go
+++ b/pkg/cmd/pr/shared/finder.go
@@ -261,7 +261,9 @@ func (f *finder) parseCurrentBranch() (string, int, error) {
 	}
 
 	if branchOwner != "" {
-		if strings.HasPrefix(branchConfig.MergeRef, "refs/heads/") {
+		if branchConfig.Push != "" {
+			prHeadRef = strings.TrimPrefix(branchConfig.Push, branchConfig.RemoteName+"/")
+		} else if strings.HasPrefix(branchConfig.MergeRef, "refs/heads/") {
 			prHeadRef = strings.TrimPrefix(branchConfig.MergeRef, "refs/heads/")
 		}
 		// prepend `OWNER:` if this branch is pushed to a fork
diff --git a/pkg/cmd/pr/shared/finder_test.go b/pkg/cmd/pr/shared/finder_test.go
index 6df8d300048..f776f2ee53c 100644
--- a/pkg/cmd/pr/shared/finder_test.go
+++ b/pkg/cmd/pr/shared/finder_test.go
@@ -232,8 +232,17 @@ func TestFind(t *testing.T) {
 					return "blueberries", nil
 				},
 				branchConfig: func(branch string) (c git.BranchConfig) {
+					c.MergeRef = "refs/heads/blueberries"
+					c.RemoteName = "origin"
+					c.Push = "origin/blueberries"
 					return
 				},
+				remotesFn: func() (context.Remotes, error) {
+					return context.Remotes{{
+						Remote: &git.Remote{Name: "origin"},
+						Repo:   ghrepo.New("OWNER", "REPO"),
+					}}, nil
+				},
 			},
 			httpStub: func(r *httpmock.Registry) {
 				r.Register(
@@ -318,6 +327,7 @@ func TestFind(t *testing.T) {
 				branchConfig: func(branch string) (c git.BranchConfig) {
 					c.MergeRef = "refs/heads/blue-upstream-berries"
 					c.RemoteName = "origin"
+					c.Push = "origin/blue-upstream-berries"
 					return
 				},
 				remotesFn: func() (context.Remotes, error) {
diff --git a/pkg/cmd/pr/status/status.go b/pkg/cmd/pr/status/status.go
index 2cd28f2edc6..b5da040af30 100644
--- a/pkg/cmd/pr/status/status.go
+++ b/pkg/cmd/pr/status/status.go
@@ -209,7 +209,9 @@ func prSelectorForCurrentBranch(gitClient *git.Client, baseRepo ghrepo.Interface
 	}
 
 	if branchOwner != "" {
-		if strings.HasPrefix(branchConfig.MergeRef, "refs/heads/") {
+		if branchConfig.Push != "" {
+			selector = strings.TrimPrefix(branchConfig.Push, branchConfig.RemoteName+"/")
+		} else if strings.HasPrefix(branchConfig.MergeRef, "refs/heads/") {
 			selector = strings.TrimPrefix(branchConfig.MergeRef, "refs/heads/")
 		}
 		// prepend `OWNER:` if this branch is pushed to a fork