Add test dynamic loading.

Author: T4rk1n

tests/integration/renderer/test_libraries.py

@@ -0,0 +1,53 @@
+from dash import Dash, html, Input, Output
+import dash_test_components as dt
+import dash_generator_test_component_standard as dgs
+
+
+def test_rblib001_dynamic_loading(dash_duo):
+    app = Dash(__name__)
+
+    app.layout = html.Div(
+        [
+            html.Button("Insert", id="insert-btn"),
+            html.Div(id="output"),
+            dgs.MyStandardComponent(id="dgs"),
+        ]
+    )
+
+    @app.callback(
+        Output("output", "children"),
+        [Input("insert-btn", "n_clicks")],
+        prevent_initial_call=True,
+    )
+    def update_output(_):
+        import dash_generator_test_component_nested as dn
+
+        return [
+            dt.StyledComponent(value="Styled", id="styled"),
+            dn.MyNestedComponent(value="nested", id="nested"),
+        ]
+
+    dash_duo.start_server(app)
+
+    def assert_unloaded(namespace):
+        assert dash_duo.driver.execute_script(
+            f"return window['{namespace}'] === undefined"
+        )
+
+    def assert_loaded(namespace):
+        assert dash_duo.driver.execute_script(
+            f"return window['{namespace}'] !== undefined"
+        )
+
+    assert_unloaded(dt.package_name)
+    assert_unloaded(dgs.package_name)
+    assert_unloaded("dash_generator_test_component_nested")
+    dash_duo.wait_for_element("#dgs")
+    assert_unloaded(dt.package_name)
+    assert_loaded(dgs.package_name)
+
+    dash_duo.wait_for_element("#insert-btn").click()
+
+    dash_duo.wait_for_element("#styled")
+    assert_loaded(dt.package_name)
+    assert_loaded("dash_generator_test_component_nested")