Remove file watcher code

Now that we refresh upon focus, we can scrap this file watching code.
Stefan says few git UIs use file watching, and I understand why: the
reason this code was problematic in the first place is that watching
files is expensive and if you have too many open file handles that
can cause problems.

Importantly: this code that's being removed was _already_ dead.

Author: jesseduffield

go.mod

@@ -9,7 +9,6 @@ require (
 	github.com/cloudfoundry/jibber_jabber v0.0.0-20151120183258-bcc4c8345a21
 	github.com/creack/pty v1.1.11
 	github.com/fsmiamoto/git-todo-parser v0.0.5
-	github.com/fsnotify/fsnotify v1.4.7
 	github.com/gdamore/tcell/v2 v2.6.0
 	github.com/go-errors/errors v1.4.2
 	github.com/gookit/color v1.4.2

go.sum

@@ -82,7 +82,6 @@ github.com/fatih/color v1.9.0/go.mod h1:eQcE1qtQxscV5RaZvpXrrb8Drkc3/DdQ+uUYCNjL
 github.com/flynn/go-shlex v0.0.0-20150515145356-3f9db97f8568/go.mod h1:xEzjJPgXI435gkrCt3MPfRiAkVrwSbHsst4LCFVfpJc=
 github.com/fsmiamoto/git-todo-parser v0.0.5 h1:Bhzd/vz/6Qm3udfkd6NO9fWfD3TpwR9ucp3N75/J5I8=
 github.com/fsmiamoto/git-todo-parser v0.0.5/go.mod h1:B+AgTbNE2BARvJqzXygThzqxLIaEWvwr2sxKYYb0Fas=
-github.com/fsnotify/fsnotify v1.4.7 h1:IXs+QLmnXW2CcXuY+8Mzv/fWEsPGWxqefPtCP5CnV9I=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/gdamore/encoding v1.0.0 h1:+7OoQ1Bc6eTm5niUzBa0Ctsh6JbMW6Ra+YNuAtDBdko=
 github.com/gdamore/encoding v1.0.0/go.mod h1:alR0ol34c49FCSBLjhosxzcPHQbf2trDkoo5dl+VrEg=

pkg/gui/controllers.go

@@ -56,7 +56,6 @@ func (gui *Gui) resetHelpersAndControllers() {
 		stagingHelper,
 		mergeConflictsHelper,
 		worktreeHelper,
-		gui.fileWatcher,
 	)
 	diffHelper := helpers.NewDiffHelper(helperCommon)
 	cherryPickHelper := helpers.NewCherryPickHelper(

pkg/gui/controllers/helpers/refresh_helper.go

@@ -28,7 +28,6 @@ type RefreshHelper struct {
 	stagingHelper        *StagingHelper
 	mergeConflictsHelper *MergeConflictsHelper
 	worktreeHelper       *WorktreeHelper
-	fileWatcher          types.IFileWatcher
 }
 
 func NewRefreshHelper(
@@ -39,7 +38,6 @@ func NewRefreshHelper(
 	stagingHelper *StagingHelper,
 	mergeConflictsHelper *MergeConflictsHelper,
 	worktreeHelper *WorktreeHelper,
-	fileWatcher types.IFileWatcher,
 ) *RefreshHelper {
 	return &RefreshHelper{
 		c:                    c,
@@ -49,7 +47,6 @@ func NewRefreshHelper(
 		stagingHelper:        stagingHelper,
 		mergeConflictsHelper: mergeConflictsHelper,
 		worktreeHelper:       worktreeHelper,
-		fileWatcher:          fileWatcher,
 	}
 }
 
@@ -548,10 +545,6 @@ func (self *RefreshHelper) refreshStateFiles() error {
 	fileTreeViewModel.SetTree()
 	fileTreeViewModel.RWMutex.Unlock()
 
-	if err := self.fileWatcher.AddFilesToFileWatcher(files); err != nil {
-		return err
-	}
-
 	return nil
 }
 

pkg/gui/file_watching.go

@@ -72,7 +72,6 @@ type Gui struct {
 	Updater              *updates.Updater
 	statusManager        *status.StatusManager
 	waitForIntro         sync.WaitGroup
-	fileWatcher          *fileWatcher
 	viewBufferManagerMap map[string]*tasks.ViewBufferManager
 	// holds a mapping of view names to ptmx's. This is for rendering command outputs
 	// from within a pty. The point of keeping track of them is so that if we re-size
@@ -476,8 +475,6 @@ func NewGui(
 		afterLayoutFuncs: make(chan func() error, 1000),
 	}
 
-	gui.WatchFilesForChanges()
-
 	gui.PopupHandler = popup.NewPopupHandler(
 		cmn,
 		func(ctx goContext.Context, opts types.CreatePopupPanelOpts) error {
@@ -680,10 +677,6 @@ func (gui *Gui) RunAndHandleError(startArgs appTypes.StartArgs) error {
 				manager.Close()
 			}
 
-			if !gui.fileWatcher.Disabled {
-				gui.fileWatcher.Watcher.Close()
-			}
-
 			close(gui.stopChan)
 
 			switch err {

pkg/gui/gui.go

@@ -282,10 +282,6 @@ const (
 	COMPLETE
 )
 
-type IFileWatcher interface {
-	AddFilesToFileWatcher(files []*models.File) error
-}
-
 // screen sizing determines how much space your selected window takes up (window
 // as in panel, not your terminal's window). Sometimes you want a bit more space
 // to see the contents of a panel, and this keeps track of how much maximisation