From cf48807cd46e97c562fc436765f1172691e714b9 Mon Sep 17 00:00:00 2001
From: Eitan Joffe <ejoffe@gmail.com>
Date: Fri, 3 Dec 2021 13:55:33 -0800
Subject: [PATCH] Add warning when running spr on remote pr branches

Fixes #96

commit-id:9a1dd589
---
 github/githubclient/client.go      |  4 ++--
 github/githubclient/client_test.go |  2 +-
 spr/spr.go                         | 12 ++++++++++--
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/github/githubclient/client.go b/github/githubclient/client.go
index bc624e8..9bf329e 100644
--- a/github/githubclient/client.go
+++ b/github/githubclient/client.go
@@ -58,7 +58,7 @@ type client struct {
 	api    *githubv4.Client
 }
 
-var pullRequestRegex = regexp.MustCompile(`pr/[a-zA-Z0-9_\-]+/([a-zA-Z0-9_\-/]+)/([a-f0-9]{8})$`)
+var BranchNameRegex = regexp.MustCompile(`pr/[a-zA-Z0-9_\-]+/([a-zA-Z0-9_\-/]+)/([a-f0-9]{8})$`)
 
 func (c *client) GetInfo(ctx context.Context, gitcmd git.GitInterface) *github.GitHubInfo {
 	if c.config.User.LogGitHubCalls {
@@ -120,7 +120,7 @@ func (c *client) GetInfo(ctx context.Context, gitcmd git.GitInterface) *github.G
 			ToBranch:   node.BaseRefName,
 		}
 
-		matches := pullRequestRegex.FindStringSubmatch(node.HeadRefName)
+		matches := BranchNameRegex.FindStringSubmatch(node.HeadRefName)
 		if matches != nil && matches[1] == branchname {
 			pullRequest.Commit = git.Commit{
 				CommitID:   matches[2],
diff --git a/github/githubclient/client_test.go b/github/githubclient/client_test.go
index 4b1378e..a56154f 100644
--- a/github/githubclient/client_test.go
+++ b/github/githubclient/client_test.go
@@ -13,7 +13,7 @@ func TestPullRequestRegex(t *testing.T) {
 	}
 
 	for _, tc := range tests {
-		matches := pullRequestRegex.FindStringSubmatch(tc.input)
+		matches := BranchNameRegex.FindStringSubmatch(tc.input)
 		if tc.branch != matches[1] {
 			t.Fatalf("expected: '%v', actual: '%v'", tc.branch, matches[1])
 		}
diff --git a/spr/spr.go b/spr/spr.go
index 6cef58f..ff34878 100644
--- a/spr/spr.go
+++ b/spr/spr.go
@@ -14,6 +14,7 @@ import (
 	"github.com/ejoffe/spr/config"
 	"github.com/ejoffe/spr/git"
 	"github.com/ejoffe/spr/github"
+	"github.com/ejoffe/spr/github/githubclient"
 	"github.com/ejoffe/spr/hook"
 )
 
@@ -381,13 +382,20 @@ func (sd *stackediff) fetchAndGetGitHubInfo(ctx context.Context) *github.GitHubI
 	sd.mustgit("fetch", nil)
 	rebaseCommand := fmt.Sprintf("rebase %s/%s --autostash",
 		sd.config.Repo.GitHubRemote, sd.config.Repo.GitHubBranch)
-	//var output string
 	err := sd.gitcmd.Git(rebaseCommand, nil)
 	if err != nil {
 		return nil
 	}
-
 	info := sd.github.GetInfo(ctx, sd.gitcmd)
+	if githubclient.BranchNameRegex.FindString(info.LocalBranch) != "" {
+		fmt.Printf("error: don't run spr in a remote pr branch\n")
+		fmt.Printf(" this could lead to weird duplicate pull requests getting created\n")
+		fmt.Printf(" in general there is no need to checkout remote branches used for prs\n")
+		fmt.Printf(" instead use local branches and run spr update to sync your commit stack\n")
+		fmt.Printf("  with your pull requests on github\n")
+		fmt.Printf("branch name: %s\n", info.LocalBranch)
+		return nil
+	}
 
 	return info
 }