Add reload setting - finalization of zyedidia#2627 (zyedidia#2845)

* Add reload setting

Can be set to:

* auto - Automatically reload files that changed
* disabled - Do not reload files
* prompt - Prompt the user about reloading the file.

* option: Add default value for reload option and documentation

---------

Co-authored-by: Wilberto Morales <wilbertomorales777@gmail.com>

Author: JoeKar

internal/action/bufpane.go

@@ -395,20 +395,34 @@ func (h *BufPane) Name() string {
 	return n
 }
 
+func (h *BufPane) getReloadSetting() string {
+	reloadSetting := h.Buf.Settings["reload"]
+	return reloadSetting.(string)
+}
+
 // HandleEvent executes the tcell event properly
 func (h *BufPane) HandleEvent(event tcell.Event) {
 	if h.Buf.ExternallyModified() && !h.Buf.ReloadDisabled {
-		InfoBar.YNPrompt("The file on disk has changed. Reload file? (y,n,esc)", func(yes, canceled bool) {
-			if canceled {
-				h.Buf.DisableReload()
-			}
-			if !yes || canceled {
-				h.Buf.UpdateModTime()
-			} else {
-				h.Buf.ReOpen()
-			}
-		})
+		reload := h.getReloadSetting()
 
+		if reload == "prompt" {
+			InfoBar.YNPrompt("The file on disk has changed. Reload file? (y,n,esc)", func(yes, canceled bool) {
+				if canceled {
+					h.Buf.DisableReload()
+				}
+				if !yes || canceled {
+					h.Buf.UpdateModTime()
+				} else {
+					h.Buf.ReOpen()
+				}
+			})
+		} else if reload == "auto" {
+			h.Buf.ReOpen()
+		} else if reload == "disabled" {
+			h.Buf.DisableReload()
+		} else {
+			InfoBar.Message("Invalid reload setting")
+		}
 	}
 
 	switch e := event.(type) {

internal/config/settings.go

@@ -52,6 +52,7 @@ var optionValidators = map[string]optionValidator{
 	"fileformat":   validateLineEnding,
 	"encoding":     validateEncoding,
 	"multiopen":    validateMultiOpen,
+	"reload":       validateReload,
 }
 
 func ReadSettings() error {
@@ -294,6 +295,7 @@ var defaultCommonSettings = map[string]interface{}{
 	"mkparents":      false,
 	"permbackup":     false,
 	"readonly":       false,
+	"reload":         "prompt",
 	"rmtrailingws":   false,
 	"ruler":          true,
 	"relativeruler":  false,
@@ -526,3 +528,19 @@ func validateMultiOpen(option string, value interface{}) error {
 
 	return nil
 }
+
+func validateReload(option string, value interface{}) error {
+	val, ok := value.(string)
+
+	if !ok {
+		return errors.New("Expected string type for reload")
+	}
+
+	switch val {
+	case "prompt", "auto", "disabled":
+	default:
+		return errors.New(option + " must be 'prompt', 'auto' or 'disabled'")
+	}
+
+	return nil
+}

runtime/help/options.md

@@ -281,6 +281,11 @@ Here are the available options:
 
     default value: `false`
 
+* `reload`: controls the reload behavior of the current buffer in case the file
+   has changed. The available options are `prompt`, `auto` & `disabled`.
+
+   default value: `prompt`
+
 * `rmtrailingws`: micro will automatically trim trailing whitespaces at ends of
    lines. Note: This setting overrides `keepautoindent`