feat: add backpack with find method (#1657)

* feat: add backpack with find method

* code review

aimmo-game-worker/simulation/avatar_state.py

@@ -1,20 +1,19 @@
 from collections import namedtuple
-from simulation.location import Location
 from typing import Dict
 
+from .backpack import Backpack
+from .location import Location
+
 
 def create_avatar_state(avatar_state_json: Dict):
     avatar_state_dict = avatar_state_json.copy()
     avatar_state_dict["location"] = Location(**avatar_state_json["location"])
 
     # check backpack as it doesn't always exist (i.e. worksheet 1)
-    if avatar_state_json.get("backpack"):
+    if "backpack" in avatar_state_json:
         # use namedtuple for artefacts to allow accessing fields by name
-        avatar_state_dict["backpack"] = [
-            namedtuple("Artefact", artefact.keys())(*artefact.values())
-            for artefact in avatar_state_json["backpack"]
-        ]
+        avatar_state_dict["backpack"] = Backpack(
+            [namedtuple("Artefact", artefact.keys())(*artefact.values()) for artefact in avatar_state_json["backpack"]]
+        )
 
-    return namedtuple("AvatarState", avatar_state_dict.keys())(
-        *avatar_state_dict.values()
-    )
+    return namedtuple("AvatarState", avatar_state_dict.keys())(*avatar_state_dict.values())

aimmo-game-worker/simulation/backpack.py

@@ -0,0 +1,24 @@
+from collections import namedtuple
+from multiprocessing.sharedctypes import Value
+from typing import TypeVar, List
+
+T = TypeVar("T")
+
+
+class Backpack(List[T]):
+    """
+    A list of artefacts that has a `find` method to find the first index of an artefact type.
+    """
+
+    def find(self, artefact_type: str) -> int:
+        """
+        Finds the first artefact of type `artefact_type` and returns its index or -1 if there's no artefact of that
+        type.
+
+        Args:
+            artefact_type: The type of artefact to find.
+
+        Returns:
+            The index of the artefact or -1 if it doesn't exist.
+        """
+        return next((i for i, artefact in enumerate(self) if artefact.type == artefact_type), -1)

aimmo-game-worker/tests/tests_simulation/test_avatar_state.py

@@ -9,10 +9,22 @@ def avatar_state_json():
     return {"location": {"x": 0, "y": 0}, "backpack": [{"type": "key"}]}
 
 
+@pytest.fixture
+def avatar_state_json_no_backpack():
+    return {"location": {"x": 1, "y": 1}}
+
+
 def test_create_avatar_state(avatar_state_json):
     avatar_state = create_avatar_state(avatar_state_json)
     avatar_loc = avatar_state_json["location"]
 
     assert avatar_state.location == Location(avatar_loc["x"], avatar_loc["y"])
-
     assert avatar_state.backpack[0].type == avatar_state_json["backpack"][0]["type"]
+
+
+def test_create_avatar_state_no_backpack(avatar_state_json_no_backpack):
+    avatar_state = create_avatar_state(avatar_state_json_no_backpack)
+    avatar_loc = avatar_state_json_no_backpack["location"]
+
+    assert avatar_state.location == Location(avatar_loc["x"], avatar_loc["y"])
+    assert not hasattr(avatar_state, "backpack")

aimmo-game-worker/tests/tests_simulation/test_backpack.py

@@ -0,0 +1,46 @@
+from collections import namedtuple
+import pytest
+
+from simulation.backpack import Backpack
+
+Artefact = namedtuple("Artefact", "type")
+
+
+@pytest.fixture
+def keyboard_artefact():
+    return Artefact("keyboard")
+
+
+@pytest.fixture
+def phone_artefact():
+    return Artefact("phone")
+
+
+@pytest.fixture
+def coins_artefact():
+    return Artefact("coins")
+
+
+@pytest.fixture
+def orb_artefact():
+    return Artefact("orb")
+
+
+@pytest.fixture
+def empty_backpack():
+    return Backpack()
+
+
+@pytest.fixture
+def backpack(keyboard_artefact, phone_artefact, coins_artefact):
+    return Backpack(
+        [keyboard_artefact, keyboard_artefact, phone_artefact, coins_artefact, phone_artefact, coins_artefact]
+    )
+
+
+def test_backpack_find(empty_backpack, backpack, keyboard_artefact, phone_artefact, coins_artefact, orb_artefact):
+    assert empty_backpack.find("test") == -1
+    assert backpack.find(keyboard_artefact.type) == 0
+    assert backpack.find(phone_artefact.type) == 2
+    assert backpack.find(coins_artefact.type) == 3
+    assert backpack.find(orb_artefact.type) == -1