chore: Validate hand length

poker/models.py

@@ -1,6 +1,8 @@
+from __future__ import annotations
+
 from pydantic import BaseModel, validator
 
-from poker.constants import Suit, Value
+from poker.constants import Rank, Suit, Value
 
 
 class Card(BaseModel):
@@ -13,18 +15,37 @@ class Card(BaseModel):
         """Hash function."""
         return hash(f"{self.value} {self.suit}")
 
+    def __le__(self, other: Card) -> bool:
+        """Less than or equal to."""
+        return self.value <= other.value
 
-HandType = tuple[Card, Card, Card, Card, Card]
+    def __lt__(self, other: Card) -> bool:
+        """Strictly less than."""
+        return self.value < other.value
 
 
 class Hand(BaseModel):
     """Hand domain model class."""
 
-    cards: HandType
+    cards: list[Card]
 
     @validator("cards")
-    def validate_unique(cls, cards: HandType) -> HandType:
+    def validate_unique(cls, cards: list[Card]) -> list[Card]:
         """Validate hand comprises unique cards."""
         if len(cards) != len(set(cards)):
             raise ValueError("Hand contains duplicate cards.")
         return cards
+
+    @validator("cards")
+    def validate_length(cls, cards: list[Card]) -> list[Card]:
+        """Validate hand has five cards."""
+        if len(cards) != 5:
+            raise ValueError("Hand must have five cards.")
+        return cards
+
+
+class RankedHand(Hand):
+    """Ranked hand  domain model class."""
+
+    rank: Rank
+    description: str