Fix "Unpin" button not showing up in overlayed widgets

Changelog

@@ -4,9 +4,7 @@
  - Co-installable with Qt6
  - Adds support for non-detachable central widget, MainWindowOption_HasCentralWidget. (#225)
  - Fix corrupt layout when restoring old JSON
-
-* v1.4.1 (unreleased)
- -
+ - Fix "Unpin" button not showing up in overlayed widgets
 
 * v1.4.0 (16 July 2021)
   - No longer supports Qt versions less than 5.12

src/private/TitleBar.cpp

@@ -285,7 +285,7 @@ bool TitleBar::supportsMinimizeButton() const
 bool TitleBar::supportsAutoHideButton() const
 {
     // Only dock widgets docked into the MainWindow can minimize
-    return m_supportsAutoHide && m_frame && m_frame->isInMainWindow();
+    return m_supportsAutoHide && m_frame && (m_frame->isInMainWindow() || m_frame->isOverlayed());
 }
 
 bool TitleBar::hasIcon() const

tests/tst_docks.cpp

@@ -5258,6 +5258,31 @@ void TestDocks::tst_deleteOnCloseWhenOnSideBar()
     QVERIFY(dock1);
 }
 
+void TestDocks::tst_sidebarOverlayShowsAutohide()
+{
+    // Tests that overlayed widgets show the "Disable auto-hide" button
+
+    EnsureTopLevelsDeleted e;
+    KDDockWidgets::Config::self().setFlags(KDDockWidgets::Config::Flag_AutoHideSupport);
+
+    auto m1 = createMainWindow(QSize(1000, 1000), MainWindowOption_None, "MW1");
+    auto dw1 = new DockWidgetType(QStringLiteral("1"));
+
+    m1->addDockWidget(dw1, Location_OnBottom);
+    QVERIFY(dw1->titleBar()->supportsAutoHideButton());
+
+    m1->moveToSideBar(dw1);
+    m1->overlayOnSideBar(dw1);
+
+    QVERIFY(dw1->isOverlayed());
+
+    auto titleBar = dw1->titleBar();
+    QVERIFY(titleBar->isVisible());
+    QVERIFY(titleBar->supportsAutoHideButton());
+
+    delete dw1;
+}
+
 void TestDocks::tst_sidebarOverlayGetsHiddenOnClick()
 {
     EnsureTopLevelsDeleted e;

tests/tst_docks.h

@@ -261,6 +261,7 @@ private Q_SLOTS:
     void tst_restoreSideBar();
     void tst_toggleActionOnSideBar();
     void tst_deleteOnCloseWhenOnSideBar();
+    void tst_sidebarOverlayShowsAutohide();
     void tst_sidebarOverlayGetsHiddenOnClick();
     void tst_floatRemovesFromSideBar();
     void tst_overlayedGeometryIsSaved();