[py][bidi]: add test for downloadEnd event (#16325)

Author: navin772

py/test/selenium/webdriver/common/bidi_browsing_context_tests.py

@@ -807,6 +807,49 @@ def on_download_will_begin(info):
     driver.browsing_context.remove_event_handler("download_will_begin", callback_id)
 
 
+@pytest.mark.xfail_firefox
+def test_add_event_handler_download_end(driver, pages):
+    """Test adding event handler for download_end event."""
+    events_received = []
+
+    def on_download_end(info):
+        events_received.append(info)
+
+    callback_id = driver.browsing_context.add_event_handler("download_end", on_download_end)
+    assert callback_id is not None
+
+    context_id = driver.current_window_handle
+    url = pages.url("downloads/download.html")
+    driver.browsing_context.navigate(context=context_id, url=url, wait=ReadinessState.COMPLETE)
+
+    driver.find_element(By.ID, "file-1").click()
+
+    driver.find_element(By.ID, "file-2").click()
+    WebDriverWait(driver, 5).until(lambda d: len(events_received) == 2)
+
+    assert len(events_received) == 2
+
+    for ev in events_received:
+        assert ev.download_params is not None
+        assert ev.download_params.status == "complete"
+        assert ev.download_params.context == context_id
+        assert ev.download_params.timestamp is not None
+
+    # we assert that atleast "file_1" is present in the downloaded file since multiple downloads
+    # will have numbered suffix like file_1 (1)
+    assert any(
+        "downloads/file_1.txt" in ev.download_params.url and "file_1" in ev.download_params.filepath
+        for ev in events_received
+    )
+
+    assert any(
+        "downloads/file_2.jpg" in ev.download_params.url and "file_2" in ev.download_params.filepath
+        for ev in events_received
+    )
+
+    driver.browsing_context.remove_event_handler("download_end", callback_id)
+
+
 def test_add_event_handler_with_specific_contexts(driver):
     """Test adding event handler with specific browsing contexts."""
     events_received = []