package command
import (
"errors"
"fmt"
"os"
"os/exec"
"github.com/spf13/cobra"
"github.com/cli/cli/git"
"github.com/cli/cli/internal/ghrepo"
"github.com/cli/cli/internal/run"
)
func prCheckout(cmd *cobra.Command, args []string) error {
ctx := contextForCommand(cmd)
currentBranch, _ := ctx.Branch()
remotes, err := ctx.Remotes()
if err != nil {
return err
}
apiClient, err := apiClientForContext(ctx)
if err != nil {
return err
}
var baseRepo ghrepo.Interface
prArg := args[0]
if prNum, repo := prFromURL(prArg); repo != nil {
prArg = prNum
baseRepo = repo
}
if baseRepo == nil {
baseRepo, err = determineBaseRepo(cmd, ctx)
if err != nil {
return err
}
}
pr, err := prFromArg(apiClient, baseRepo, prArg)
if err != nil {
return err
}
baseRemote, _ := remotes.FindByRepo(baseRepo.RepoOwner(), baseRepo.RepoName())
// baseRemoteSpec is a repository URL or a remote name to be used in git fetch
baseURLOrName := formatRemoteURL(cmd, ghrepo.FullName(baseRepo))
if baseRemote != nil {
baseURLOrName = baseRemote.Name
}
headRemote := baseRemote
if pr.IsCrossRepository {
headRemote, _ = remotes.FindByRepo(pr.HeadRepositoryOwner.Login, pr.HeadRepository.Name)
}
var cmdQueue [][]string
newBranchName := pr.HeadRefName
if headRemote != nil {
// there is an existing git remote for PR head
remoteBranch := fmt.Sprintf("%s/%s", headRemote.Name, pr.HeadRefName)
refSpec := fmt.Sprintf("+refs/heads/%s:refs/remotes/%s", pr.HeadRefName, remoteBranch)
cmdQueue = append(cmdQueue, []string{"git", "fetch", headRemote.Name, refSpec})
// local branch already exists
if _, err := git.ShowRefs("refs/heads/" + newBranchName); err == nil {
cmdQueue = append(cmdQueue, []string{"git", "checkout", newBranchName})
cmdQueue = append(cmdQueue, []string{"git", "merge", "--ff-only", fmt.Sprintf("refs/remotes/%s", remoteBranch)})
} else {
cmdQueue = append(cmdQueue, []string{"git", "checkout", "-b", newBranchName, "--no-track", remoteBranch})
cmdQueue = append(cmdQueue, []string{"git", "config", fmt.Sprintf("branch.%s.remote", newBranchName), headRemote.Name})
cmdQueue = append(cmdQueue, []string{"git", "config", fmt.Sprintf("branch.%s.merge", newBranchName), "refs/heads/" + pr.HeadRefName})
}
} else {
// no git remote for PR head
// avoid naming the new branch the same as the default branch
if newBranchName == pr.HeadRepository.DefaultBranchRef.Name {
newBranchName = fmt.Sprintf("%s/%s", pr.HeadRepositoryOwner.Login, newBranchName)
}
ref := fmt.Sprintf("refs/pull/%d/head", pr.Number)
if newBranchName == currentBranch {
// PR head matches currently checked out branch
cmdQueue = append(cmdQueue, []string{"git", "fetch", baseURLOrName, ref})
cmdQueue = append(cmdQueue, []string{"git", "merge", "--ff-only", "FETCH_HEAD"})
} else {
// create a new branch
cmdQueue = append(cmdQueue, []string{"git", "fetch", baseURLOrName, fmt.Sprintf("%s:%s", ref, newBranchName)})
cmdQueue = append(cmdQueue, []string{"git", "checkout", newBranchName})
}
remote := baseURLOrName
mergeRef := ref
if pr.MaintainerCanModify {
remote = formatRemoteURL(cmd, fmt.Sprintf("%s/%s", pr.HeadRepositoryOwner.Login, pr.HeadRepository.Name))
mergeRef = fmt.Sprintf("refs/heads/%s", pr.HeadRefName)
}
if mc, err := git.Config(fmt.Sprintf("branch.%s.merge", newBranchName)); err != nil || mc == "" {
cmdQueue = append(cmdQueue, []string{"git", "config", fmt.Sprintf("branch.%s.remote", newBranchName), remote})
cmdQueue = append(cmdQueue, []string{"git", "config", fmt.Sprintf("branch.%s.merge", newBranchName), mergeRef})
}
}
for _, args := range cmdQueue {
cmd := exec.Command(args[0], args[1:]...)
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
if err := run.PrepareCmd(cmd).Run(); err != nil {
return err
}
}
return nil
}
var prCheckoutCmd = &cobra.Command{
Use: "checkout { | | }",
Short: "Check out a pull request in Git",
Args: func(cmd *cobra.Command, args []string) error {
if len(args) < 1 {
return errors.New("requires a pull request number as an argument")
}
return nil
},
RunE: prCheckout,
}