Wrong type checking on TypedDict with optional parameters

[NixBiks]

Environment data

• Language Server version: 2020.6.1
• OS and version: Debian GNU/Linux 10 (buster)
• Python version (& distribution if applicable, e.g. Anaconda): Python 3.8.3

Expected behaviour

I'd expect pylance to not flag any issues with the following code that passes just fine.

from typing import Optional, List, TypedDict


class SubOrder(TypedDict):
    name: str


class Order(TypedDict):
    name: str
    sub_orders: Optional[List[SubOrder]]


assert Order(name="Pizza") == {"name": "Pizza"}
assert Order(name="Pizza", sub_orders=[SubOrder(name="Pasta")]) == {
    "name": "Pizza",
    "sub_orders": [{"name": "Pasta"}],
}

Actual behaviour

However I get the following message regarding the line with Order(name="Pizza").

Argument missing for parameter "sub_orders"

Another issue is that the IntelliSense doesn't seem to work either. It just shows Order(*kwargs, **kwargs) when I start typing Order(

[FrozenBob]

This behavior is correct. "Runs fine" doesn't say anything about whether your static types are correct, and your static types are not in fact correct. Your Order is defined as requiring an entry for 'sub_orders'. That entry may be set to None, but it must not be entirely absent.

[NixBiks]

Hmm okay. Is it possible to achieve what I want then? I've tried fiddling with Union of two Order types, one with sub_orders and one without. No luck though.

[erictraut]

If you want to specify that some of the keys within the TypedDict can be completely absent, you can use total=False in its definition, like this:

class Order(TypedDict, total=False):
    name: str
    sub_orders: Optional[List[SubOrder]]

For more details about TypedDict, see PEP 589 documentation.

[NixBiks]

Alright thanks for your answers and a great product