Dirfirst option and numerical sorting (#27)

* Create option dirfirst, and add numerical sorting

* Add only dirfirst option

comp.go

@@ -49,6 +49,9 @@ var (
 		"preview",
 		"nopreview",
 		"preview!",
+		"dirfirst",
+		"nodirfirst",
+		"dirfirst!",
 		"scrolloff",
 		"tabstop",
 		"ifs",

doc.go

@@ -46,6 +46,7 @@ The following options can be used to customize the behavior of lf.
 
     hidden     bool    (default off)
     preview    bool    (default on)
+    dirfirst   bool    (default on)
     scrolloff  int     (default 0)
     tabstop    int     (default 8)
     ifs        string  (default "") (not exported if empty)

docstring.go

@@ -50,6 +50,7 @@ The following options can be used to customize the behavior of lf.
 
     hidden     bool    (default off)
     preview    bool    (default on)
+    dirfirst   bool    (default on)
     scrolloff  int     (default 0)
     tabstop    int     (default 8)
     ifs        string  (default "") (not exported if empty)

eval.go

@@ -26,6 +26,15 @@ func (e *SetExpr) eval(app *App, args []string) {
 		gOpts.preview = false
 	case "preview!":
 		gOpts.preview = !gOpts.preview
+	case "dirfirst":
+		gOpts.dirfirst = true
+		app.nav.renew(app.nav.height)
+	case "nodirfirst":
+		gOpts.dirfirst = false
+		app.nav.renew(app.nav.height)
+	case "dirfirst!":
+		gOpts.dirfirst = !gOpts.dirfirst
+		app.nav.renew(app.nav.height)
 	case "scrolloff":
 		n, err := strconv.Atoi(e.val)
 		if err != nil {

nav.go

@@ -107,9 +107,11 @@ func organizeFiles(fi []os.FileInfo) []os.FileInfo {
 		log.Printf("unknown sorting type: %s", gOpts.sortby)
 	}
 
-	// TODO: these should be optional
+	if gOpts.dirfirst {
+		sort.Stable(ByDir(fi))
+	}
+	//TODO this should be optional
 	sort.Stable(ByNum(fi))
-	sort.Stable(ByDir(fi))
 
 	return fi
 }

opts.go

@@ -10,6 +10,7 @@ var gOpts struct {
 	shell     string
 	showinfo  string
 	sortby    string
+	dirfirst  bool
 	ratios    []int
 	keys      map[string]Expr
 	cmds      map[string]Expr
@@ -23,6 +24,7 @@ func init() {
 	gOpts.shell = envShell
 	gOpts.showinfo = "none"
 	gOpts.sortby = "name"
+	gOpts.dirfirst = true
 	gOpts.ratios = []int{1, 2, 3}
 
 	gOpts.keys = make(map[string]Expr)