QQuickRangeSlider: don't crash on press with null handles

The handle visuals should be optional. There were a few missing checks
for null pointers.

Change-Id: I13e38f373428dbe0c8e338442370fbe7bb02c15a
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/auto/controls/data/tst_rangeslider.qml b/tests/auto/controls/data/tst_rangeslider.qml
index 69ec6218..da6e24a1 100644
--- a/tests/auto/controls/data/tst_rangeslider.qml
+++ b/tests/auto/controls/data/tst_rangeslider.qml
@@ -896,4 +896,31 @@ TestCase {
         mouseMove(control, node.handle.x - 1, node.handle.y - 1)
         compare(node.hovered, false)
     }
+
+    function test_nullHandles() {
+        var control = createTemporaryObject(sliderComponent, testCase, {"second.value": 1})
+        verify(control)
+
+        verify(control.first.handle)
+        verify(control.second.handle)
+
+        control.first.handle = null
+        control.second.handle = null
+
+        mousePress(control, control.leftPadding, control.height / 2)
+        verify(control.first.pressed, true)
+        compare(control.second.pressed, false)
+
+        mouseRelease(control, control.leftPadding, control.height / 2)
+        compare(control.first.pressed, false)
+        compare(control.second.pressed, false)
+
+        mousePress(control, control.width - control.rightPadding, control.height / 2)
+        compare(control.first.pressed, false)
+        compare(control.second.pressed, true)
+
+        mouseRelease(control, control.width - control.rightPadding, control.height / 2)
+        compare(control.first.pressed, false)
+        compare(control.second.pressed, false)
+    }
 }