Fix incorrect scrolling when Wrap is set to true

_examples/wrap_autoscroll.go

@@ -0,0 +1,70 @@
+// Copyright 2014 The gocui Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"errors"
+	"fmt"
+	"log"
+
+	"github.com/awesome-gocui/gocui"
+)
+
+var tabCount = 0
+
+func main() {
+	g, err := gocui.NewGui(gocui.OutputNormal, true)
+	if err != nil {
+		log.Panicln(err)
+	}
+	defer g.Close()
+
+	g.SetManagerFunc(layout)
+
+	if err := g.SetKeybinding("", gocui.KeyCtrlC, gocui.ModNone, quit); err != nil {
+		log.Panicln(err)
+	}
+	if err := g.SetKeybinding("", gocui.KeyTab, gocui.ModNone, print); err != nil {
+		log.Panicln(err)
+	}
+
+	if err := g.MainLoop(); err != nil && !errors.Is(err, gocui.ErrQuit) {
+		log.Panicln(err)
+	}
+}
+
+func layout(g *gocui.Gui) error {
+	maxX, maxY := g.Size()
+	if v, err := g.SetView("main", maxX/2-7, maxY/2-1, maxX/2+7, maxY/2+4, 0); err != nil {
+		if !errors.Is(err, gocui.ErrUnknownView) {
+			return err
+		}
+
+		if _, err := g.SetCurrentView("main"); err != nil {
+			return err
+		}
+		v.Clear()
+		v.Autoscroll = true
+		v.Wrap = true
+
+		fmt.Fprintln(v, "Hello world!")
+	}
+
+	return nil
+}
+
+func print(g *gocui.Gui, v *gocui.View) error {
+	tabCount++
+	if tabCount%10 == 0 {
+		fmt.Fprintln(v, tabCount, "Hello!")
+	} else {
+		fmt.Fprintln(v, tabCount, "Hello Cruel World !")
+	}
+	return nil
+}
+
+func quit(g *gocui.Gui, v *gocui.View) error {
+	return gocui.ErrQuit
+}

view.go

@@ -572,7 +572,7 @@ func (v *View) draw() error {
 	linesToRender := v.viewLines()
 
 	if v.Autoscroll && len(linesToRender) > maxY {
-		v.oy = len(v.lines) - maxY
+		v.oy = len(linesToRender) - maxY - 1
 	}
 
 	newCache := []cellCache{}