From 066d988de1ba44102cfb9df0b7ec0285f891246a Mon Sep 17 00:00:00 2001
From: Pavel <pavel.feldman@gmail.com>
Date: Sun, 2 Aug 2020 15:24:40 -0700
Subject: [PATCH] feat(gather): introduce sync gather for easier async tests
 migration

---
 playwright/sync_base.py | 34 +++++++++++++++++++++++++++++++++-
 tests/sync/test_sync.py | 10 ++++++++++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/playwright/sync_base.py b/playwright/sync_base.py
index 3247ee7fc9..c9577adfc6 100644
--- a/playwright/sync_base.py
+++ b/playwright/sync_base.py
@@ -13,7 +13,8 @@
 # limitations under the License.
 
 import asyncio
-from typing import Any, Callable, Coroutine, Generic, Optional, TypeVar, cast
+import sys
+from typing import Any, Callable, Coroutine, Dict, Generic, List, Optional, TypeVar, cast
 
 import greenlet
 
@@ -109,3 +110,34 @@ def once(self, event_name: str, handler: Any) -> None:
 
     def remove_listener(self, event_name: str, handler: Any) -> None:
         self._impl_obj.remove_listener(event_name, handler)
+
+    def _gather(self, actions: List[Callable]) -> List[Any]:
+        g_self = greenlet.getcurrent()
+        results: Dict[Callable, Any] = {}
+        exceptions: List[Exception] = []
+
+        def action_wrapper(action):
+            def body():
+                try:
+                    results[action] = action()
+                except Exception as e:
+                    results[action] = e
+                    exceptions.append(e)
+                g_self.switch()
+            return body
+
+        async def task():
+            for action in actions:
+                g = greenlet.greenlet(action_wrapper(action))
+                g.switch()
+
+        self._loop.create_task(task())
+
+        while len(results) < len(actions):
+            dispatcher_fiber_.switch()
+
+        asyncio._set_running_loop(self._loop)
+        if exceptions:
+            raise exceptions[0]
+
+        return list(map(lambda action: results[action], actions))
diff --git a/tests/sync/test_sync.py b/tests/sync/test_sync.py
index db69413fbe..ebe193537b 100644
--- a/tests/sync/test_sync.py
+++ b/tests/sync/test_sync.py
@@ -187,3 +187,13 @@ def test_sync_set_default_timeout(page):
     with pytest.raises(TimeoutError) as exc:
         page.waitForFunction("false")
     assert "Timeout 1ms exceeded." in exc.value.message
+
+
+def test_close_should_reject_all_promises(context):
+    new_page = context.newPage()
+    with pytest.raises(Error) as exc_info:
+        new_page._gather([
+            lambda: new_page.evaluate("() => new Promise(r => {})"),
+            lambda: new_page.close()
+        ])
+    assert "Protocol error" in exc_info.value.message