Store Common instead of just the list of configured main branches in MainBranches

This will make it possible to change the configured main branches at runtime.
We'll support this in the next commit.

pkg/commands/git_commands/main_branches.go

@@ -5,17 +5,17 @@ import (
 	"sync"
 
 	"github.com/jesseduffield/lazygit/pkg/commands/oscommands"
+	"github.com/jesseduffield/lazygit/pkg/common"
 	"github.com/jesseduffield/lazygit/pkg/utils"
 	"github.com/samber/lo"
 	"github.com/sasha-s/go-deadlock"
 )
 
 type MainBranches struct {
-	// List of main branches configured by the user. Just the bare names.
-	configuredMainBranches []string
-	// Which of these actually exist in the repository. Full ref names, and it
-	// could be either "refs/heads/..." or "refs/remotes/origin/..." depending
-	// on which one exists for a given bare name.
+	c *common.Common
+	// Which of the configured main branches actually exist in the repository. Full
+	// ref names, and it could be either "refs/heads/..." or "refs/remotes/origin/..."
+	// depending on which one exists for a given bare name.
 	existingMainBranches []string
 
 	cmd   oscommands.ICmdObjBuilder
@@ -23,14 +23,14 @@ type MainBranches struct {
 }
 
 func NewMainBranches(
-	configuredMainBranches []string,
+	cmn *common.Common,
 	cmd oscommands.ICmdObjBuilder,
 ) *MainBranches {
 	return &MainBranches{
-		configuredMainBranches: configuredMainBranches,
-		existingMainBranches:   nil,
-		cmd:                    cmd,
-		mutex:                  &deadlock.Mutex{},
+		c:                    cmn,
+		existingMainBranches: nil,
+		cmd:                  cmd,
+		mutex:                &deadlock.Mutex{},
 	}
 }
 
@@ -75,9 +75,10 @@ func (self *MainBranches) determineMainBranches() []string {
 	var existingBranches []string
 	var wg sync.WaitGroup
 
-	existingBranches = make([]string, len(self.configuredMainBranches))
+	configuredMainBranches := self.c.UserConfig().Git.MainBranches
+	existingBranches = make([]string, len(configuredMainBranches))
 
-	for i, branchName := range self.configuredMainBranches {
+	for i, branchName := range configuredMainBranches {
 		wg.Add(1)
 		go utils.Safe(func() {
 			defer wg.Done()