fix(download): support download.failure() is None (#2409)

fix(download): support download.failure() == Node

playwright/_impl/_artifact.py

@@ -42,7 +42,10 @@ async def save_as(self, path: Union[str, Path]) -> None:
         await stream.save_as(path)
 
     async def failure(self) -> Optional[str]:
-        return patch_error_message(await self._channel.send("failure"))
+        reason = await self._channel.send("failure")
+        if reason is None:
+            return None
+        return patch_error_message(reason)
 
     async def delete(self) -> None:
         await self._channel.send("delete")

playwright/_impl/_helper.py

@@ -229,7 +229,7 @@ def patch_error_message(message: str) -> str:
     if match:
         message = to_snake_case(match.group(1)) + match.group(2)
     message = message.replace(
-        "Pass { acceptDownloads: true }", "Pass { accept_downloads: True }"
+        "Pass { acceptDownloads: true }", "Pass 'accept_downloads=True'"
     )
     return message
 

tests/async/test_download.py

@@ -65,6 +65,7 @@ async def test_should_report_downloads_with_accept_downloads_false(
         == f"<Download url={download.url!r} suggested_filename={download.suggested_filename!r}>"
     )
     assert await download.path()
+    assert await download.failure() is None
 
 
 async def test_should_report_downloads_with_accept_downloads_true(
@@ -180,9 +181,13 @@ async def test_should_error_when_saving_with_downloads_disabled(
     with pytest.raises(Error) as exc:
         await download.save_as(user_path)
     assert (
-        "Pass { accept_downloads: True } when you are creating your browser context"
+        "Pass 'accept_downloads=True' when you are creating your browser context"
         in exc.value.message
     )
+    assert (
+        "Pass 'accept_downloads=True' when you are creating your browser context."
+        == await download.failure()
+    )
     await page.close()