Add type annotations

[rpdelaney]

Is your feature request related to a problem? Please describe.

Consider this class:

from steam.steamid import SteamID

from typing import Generator, List, Tuple, Union

bans: List[str] = []

class Player:
    def __init__(self, name: str, steamid_64: str) -> None:
        self.name = name
        self.steamid_64 = steamid_64

    @property
    def steamid(self) -> str:
        try:
            return SteamID(self.steamid_64).as_steam2
        except ValueError:
            return ""

    @property
    def valid_steamid(self) -> bool:
        try:
            return SteamID.is_valid(SteamID(self.steamid_64))
        except ValueError:
            return False

    @property
    def is_banned(self) -> bool:
        return self.steamid in bans

    @property
    def url(self) -> str:
        try:
            return SteamID(self.steamid_64).community_url
        except ValueError:
            return ""

    def __iter__(self) -> Generator[Tuple[str, Union[int, str]], None, None]:
        yield "name", self.name
        yield "steamid64", self.steamid_64
        yield "steamid", self.steamid
        yield "valid_steamid", self.valid_steamid
        yield "is_banned", self.is_banned
        yield "url", self.url

Because the instance methods in the steam module are untyped, mypy gives errors:

foo.py:16:13: error: Returning Any from function declared to return "str"  [no-any-return]
foo.py:23:13: error: Returning Any from function declared to return "bool"  [no-any-return]
foo.py:34:13: error: Returning Any from function declared to return "str"  [no-any-return]
Found 3 errors in 1 file (checked 1 source file)

To silence the warnings, I must coerce the returned expressions:

diff --git i/foo.py w/foo.py
index f1f6722..d15cbb6 100644
--- i/foo.py
+++ w/foo.py
@@ -13,14 +13,14 @@ class Player:
     @property
     def steamid(self) -> str:
         try:
-            return SteamID(self.steamid_64).as_steam2
+            return str(SteamID(self.steamid_64).as_steam2)
         except ValueError:
             return ""

     @property
     def valid_steamid(self) -> bool:
         try:
-            return SteamID.is_valid(SteamID(self.steamid_64))
+            return bool(SteamID.is_valid(SteamID(self.steamid_64)))
         except ValueError:
             return False

@@ -31,7 +31,7 @@ class Player:
     @property
     def url(self) -> str:
         try:
-            return SteamID(self.steamid_64).community_url
+            return str(SteamID(self.steamid_64).community_url)
         except ValueError:
             return ""

Describe the solution you'd like

• steam should return typed values.

This would aid consumers in type checking their code that depends on steam.

• Stretch goal: add type checking to this repository.

That would guard against returning wrong types as the module develops.

Describe alternatives you've considered

• Do nothing.

The easiest option. It's not so inconvenient to coerce or annotate types in my code. But the tools are available in python, and I think it's worth considering.

Thanks for reading. Happy to answer questions.

[Gobot1234]

This is being worked on (see #286) but it will have to wait until V3 as Python 2 support won't be dropped until then.