DocTabs Indicator remains visible after last tab is removed

[pbrown12303]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

If you remove all tabs from DocTabs, the selected indicator for the last tab remains visible.

How to reproduce

Run the attached test case. The first time will fail because the testdata is not present. Copy the failed files to the testdata folder and rerun - it will now run and pass all tests. Now compare emptyTabs.xml to afterTabRemoval.xml. The indicator rectangle which has a size of zero in emptyTabs now has an actual size and position in afterTabRemoval. Performing a DocTabs.SelectItem(-1) or DocTabs.Refresh() has no effect.

Screenshots

Example code

package container

import (
	"testing"
	"time"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/test"
	"fyne.io/fyne/v2/widget"
)

func TestEntryTextSize(t *testing.T) {
	tabs := container.NewDocTabs()
	tabs.Resize(fyne.NewSize(100, 100))
	tab1 := &container.TabItem{Text: "Test1", Content: widget.NewLabel("Test1")}
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "emptyTabs.xml", tabs)
	tabs.Append(tab1)
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "oneTab.xml", tabs)
	tabs.Select(tab1)
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "afterOneTabSelected.xml", tabs)
	tabs.Remove(tab1)
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "afterTabRemoval.xml", tabs)
	tabs.Refresh()
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "afterRefresh.xml", tabs)
	tabs.SelectIndex(-1)
	time.Sleep(1000 * time.Millisecond)
	test.AssertObjectRendersToMarkup(t, "afterSelectMinusOne.xml", tabs)
}

Fyne version

2.3.5

Go compiler version

1.21.0

Operating system and version

Windows 10

Additional Information

Here's the full test project, including testdata:

fyneDocTabsIndicatorTest.zip

[andydotxyz]

Thanks to @pbrown12303 this is now fixed on develop and will go into v2.4.1