add file watching for modified files

log createErrorPanel error

swallow error when adding file to watcher

3 files changed, 101 insertions, 17 deletions

diff --git a/pkg/gui/file_watching.go b/pkg/gui/file_watching.go
new file mode 100644
index 000000000..90fb32639
--- /dev/null
+++ b/pkg/gui/file_watching.go
@@ -0,0 +1,64 @@
+package gui
+
+import (
+	"os"
+	"path/filepath"
+
+	"github.com/fsnotify/fsnotify"
+	"github.com/jesseduffield/lazygit/pkg/commands"
+)
+
+// NOTE: given that we often edit files ourselves, this may make us end up refreshing files too often
+// TODO: consider watching the whole directory recursively (could be more expensive)
+func (gui *Gui) watchFilesForChanges() {
+	var err error
+	gui.fileWatcher, err = fsnotify.NewWatcher()
+	if err != nil {
+		gui.Log.Error(err)
+		return
+	}
+	go func() {
+		for {
+			select {
+			// watch for events
+			case event := <-gui.fileWatcher.Events:
+				if event.Op == fsnotify.Chmod {
+					// for some reason we pick up chmod events when they don't actually happen
+					continue
+				}
+				// only refresh if we're not already
+				if !gui.State.IsRefreshingFiles {
+					if err := gui.refreshFiles(); err != nil {
+						err = gui.createErrorPanel(gui.g, err.Error())
+						if err != nil {
+							gui.Log.Error(err)
+						}
+					}
+				}
+
+			// watch for errors
+			case err := <-gui.fileWatcher.Errors:
+				if err != nil {
+					gui.Log.Warn(err)
+				}
+			}
+		}
+	}()
+}
+
+func (gui *Gui) addFilesToFileWatcher(files []*commands.File) error {
+	// watch the files for changes
+	dirName, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	for _, file := range files {
+		if err := gui.fileWatcher.Add(filepath.Join(dirName, file.Name)); err != nil {
+			// swallowing errors here because it doesn't really matter if we can't watch a file
+			gui.Log.Warn(err)
+		}
+	}
+
+	return nil
+}
diff --git a/pkg/gui/files_panel.go b/pkg/gui/files_panel.go
index af021c132..ae3328eed 100644
--- a/pkg/gui/files_panel.go
+++ b/pkg/gui/files_panel.go
@@ -105,6 +105,13 @@ func (gui *Gui) handleFileSelect(g *gocui.Gui, v *gocui.View, alreadySelected bo
 }
 
 func (gui *Gui) refreshFiles() error {
+	gui.State.RefreshingFilesMutex.Lock()
+	gui.State.IsRefreshingFiles = true
+	defer func() {
+		gui.State.IsRefreshingFiles = false
+		gui.State.RefreshingFilesMutex.Unlock()
+	}()
+
 	selectedFile, _ := gui.getSelectedFile(gui.g)
 
 	filesView := gui.getFilesView()
@@ -126,7 +133,7 @@ func (gui *Gui) refreshFiles() error {
 		}
 		fmt.Fprint(filesView, list)
 
-		if filesView == g.CurrentView() {
+		if g.CurrentView() == filesView || (g.CurrentView() == gui.getMainView() && gui.State.Context == "merging") {
 			newSelectedFile, _ := gui.getSelectedFile(gui.g)
 			alreadySelected := newSelectedFile.Name == selectedFile.Name
 			return gui.handleFileSelect(g, filesView, alreadySelected)
@@ -387,6 +394,11 @@ func (gui *Gui) refreshStateFiles() error {
 	// get files to stage
 	files := gui.GitCommand.GetStatusFiles()
 	gui.State.Files = gui.GitCommand.MergeStatusFiles(gui.State.Files, files)
+
+	if err := gui.addFilesToFileWatcher(files); err != nil {
+		return err
+	}
+
 	gui.refreshSelectedLine(&gui.State.Panels.Files.SelectedLine, len(gui.State.Files))
 	return gui.updateWorkTreeState()
 }
diff --git a/pkg/gui/gui.go b/pkg/gui/gui.go
index 982e1879c..a3bcb1666 100644
--- a/pkg/gui/gui.go
+++ b/pkg/gui/gui.go
@@ -14,6 +14,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/fsnotify/fsnotify"
 	"github.com/go-errors/errors"
 
 	// "strings"
@@ -79,6 +80,7 @@ type Gui struct {
 	statusManager *statusManager
 	credentials   credentials
 	waitForIntro  sync.WaitGroup
+	fileWatcher   *fsnotify.Watcher
 }
 
 // for now the staging panel state, unlike the other panel states, is going to be
@@ -145,22 +147,24 @@ type panelStates struct {
 }
 
 type guiState struct {
-	Files               []*commands.File
-	Branches            []*commands.Branch
-	Commits             []*commands.Commit
-	StashEntries        []*commands.StashEntry
-	CommitFiles         []*commands.CommitFile
-	DiffEntries         []*commands.Commit
-	MenuItemCount       int // can't store the actual list because it's of interface{} type
-	PreviousView        string
-	Platform            commands.Platform
-	Updating            bool
-	Panels              *panelStates
-	WorkingTreeState    string // one of "merging", "rebasing", "normal"
-	Context             string // important not to set this value directly but to use gui.changeContext("new context")
-	CherryPickedCommits []*commands.Commit
-	SplitMainPanel      bool
-	RetainOriginalDir   bool
+	Files                []*commands.File
+	Branches             []*commands.Branch
+	Commits              []*commands.Commit
+	StashEntries         []*commands.StashEntry
+	CommitFiles          []*commands.CommitFile
+	DiffEntries          []*commands.Commit
+	MenuItemCount        int // can't store the actual list because it's of interface{} type
+	PreviousView         string
+	Platform             commands.Platform
+	Updating             bool
+	Panels               *panelStates
+	WorkingTreeState     string // one of "merging", "rebasing", "normal"
+	Context              string // important not to set this value directly but to use gui.changeContext("new context")
+	CherryPickedCommits  []*commands.Commit
+	SplitMainPanel       bool
+	RetainOriginalDir    bool
+	IsRefreshingFiles    bool
+	RefreshingFilesMutex sync.Mutex
 }
 
 // for now the split view will always be on
@@ -204,6 +208,8 @@ func NewGui(log *logrus.Entry, gitCommand *commands.GitCommand, oSCommand *comma
 		statusManager: &statusManager{},
 	}
 
+	gui.watchFilesForChanges()
+
 	gui.GenerateSentinelErrors()
 
 	return gui, nil
@@ -786,6 +792,8 @@ func (gui *Gui) RunWithSubprocesses() error {
 					}
 				}
 
+				gui.fileWatcher.Close()
+
 				break
 			} else if err == gui.Errors.ErrSwitchRepo {
 				continue