Add option to (un)set upstream for a local branch

pkg/gui/controllers/helpers/upstream_helper.go

@@ -0,0 +1,78 @@
+package helpers
+
+import (
+	"errors"
+	"strings"
+
+	"github.com/jesseduffield/lazygit/pkg/commands/models"
+	"github.com/jesseduffield/lazygit/pkg/gui/types"
+)
+
+type UpstreamHelper struct {
+	c     *types.HelperCommon
+	model *types.Model
+
+	getRemoteBranchesSuggestionsFunc func(string) func(string) []*types.Suggestion
+}
+
+type IUpstreamHelper interface {
+	ParseUpstream(string) (string, string, error)
+	PromptForUpstream(*models.Branch, func(string) error) error
+	GetSuggestedRemote() string
+}
+
+var _ IUpstreamHelper = &UpstreamHelper{}
+
+func NewUpstreamHelper(
+	c *types.HelperCommon,
+	model *types.Model,
+	getRemoteBranchesSuggestionsFunc func(string) func(string) []*types.Suggestion,
+) *UpstreamHelper {
+	return &UpstreamHelper{
+		c:                                c,
+		model:                            model,
+		getRemoteBranchesSuggestionsFunc: getRemoteBranchesSuggestionsFunc,
+	}
+}
+
+func (self *UpstreamHelper) ParseUpstream(upstream string) (string, string, error) {
+	var upstreamBranch, upstreamRemote string
+	split := strings.Split(upstream, " ")
+	if len(split) != 2 {
+		return "", "", errors.New(self.c.Tr.InvalidUpstream)
+	}
+
+	upstreamRemote = split[0]
+	upstreamBranch = split[1]
+
+	return upstreamRemote, upstreamBranch, nil
+}
+
+func (self *UpstreamHelper) PromptForUpstream(currentBranch *models.Branch, onConfirm func(string) error) error {
+	suggestedRemote := self.GetSuggestedRemote()
+
+	return self.c.Prompt(types.PromptOpts{
+		Title:               self.c.Tr.EnterUpstream,
+		InitialContent:      suggestedRemote + " " + currentBranch.Name,
+		FindSuggestionsFunc: self.getRemoteBranchesSuggestionsFunc(" "),
+		HandleConfirm:       onConfirm,
+	})
+}
+
+func (self *UpstreamHelper) GetSuggestedRemote() string {
+	return getSuggestedRemote(self.model.Remotes)
+}
+
+func getSuggestedRemote(remotes []*models.Remote) string {
+	if len(remotes) == 0 {
+		return "origin"
+	}
+
+	for _, remote := range remotes {
+		if remote.Name == "origin" {
+			return remote.Name
+		}
+	}
+
+	return remotes[0].Name
+}