add pytest for ui.open with new_tab

tests/test_open.py

@@ -0,0 +1,18 @@
+import pytest
+
+from nicegui import ui
+
+from .screen import Screen
+
+
+@pytest.mark.parametrize('new_tab', [False, True])
+def test_open_page(screen: Screen, new_tab: bool):
+    @ui.page('/test_page')
+    def page():
+        ui.label('Test page')
+    ui.button('Open test page', on_click=lambda: ui.open('/test_page', new_tab=new_tab))
+
+    screen.open('/')
+    screen.click('Open test page')
+    screen.switch_to(1 if new_tab else 0)
+    screen.should_contain('Test page')