feat: added BrowserType.connect slow_mo param (microsoft#674)

kumaraditya303 · web-flow · commit 5fb729bc9cf7 · 2021-05-11T20:37:21.000+02:00
diff --git a/playwright/_impl/_browser_type.py b/playwright/_impl/_browser_type.py
@@ -178,7 +178,9 @@ async def connect(
         if timeout is None:
             timeout = 30000
 
-        transport = WebSocketTransport(self._connection._loop, ws_endpoint, headers)
+        transport = WebSocketTransport(
+            self._connection._loop, ws_endpoint, headers, slow_mo
+        )
         connection = Connection(
             self._connection._dispatcher_fiber,
             self._connection._object_factory,
diff --git a/playwright/_impl/_transport.py b/playwright/_impl/_transport.py
@@ -149,13 +149,15 @@ def __init__(
         loop: asyncio.AbstractEventLoop,
         ws_endpoint: str,
         headers: Dict[str, str] = None,
+        slow_mo: float = None,
     ) -> None:
         super().__init__(loop)
         Transport.__init__(self, loop)
 
         self._stopped = False
         self.ws_endpoint = ws_endpoint
         self.headers = headers
+        self.slow_mo = slow_mo
 
     def request_stop(self) -> None:
         self._stopped = True
@@ -179,6 +181,8 @@ async def run(self) -> None:
         while not self._stopped:
             try:
                 message = await self._connection.recv()
+                if self.slow_mo is not None:
+                    await asyncio.sleep(self.slow_mo / 1000)
                 if self._stopped:
                     self.on_error_future.set_exception(
                         Error("Playwright connection closed")
diff --git a/tests/sync/test_browsertype_connect.py b/tests/sync/test_browsertype_connect.py
@@ -12,12 +12,28 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import time
+
 import pytest
 
 from playwright.sync_api import BrowserType, Error
 from tests.server import Server
 
 
+def test_browser_type_connect_slow_mo(
+    server: Server, browser_type: BrowserType, launch_server
+):
+    remote_server = launch_server()
+    browser = browser_type.connect(remote_server.ws_endpoint, slow_mo=100)
+    browser_context = browser.new_context()
+    page = browser_context.new_page()
+    t1 = time.monotonic()
+    assert page.evaluate("11 * 11") == 121
+    assert (time.monotonic() - t1) >= 0.100
+    page.goto(server.EMPTY_PAGE)
+    browser.close()
+
+
 def test_browser_type_connect_should_be_able_to_reconnect_to_a_browser(
     server: Server, browser_type: BrowserType, launch_server
 ):
