day17: coverage

day17/lib/classes.py

@@ -46,16 +46,19 @@ def __init__(self, num_rows: int, num_cols: int, cache_min: int, cache_max: int)
         ]
 
     def add_solution(self, step: Step) -> bool:
-        """adds solution to cache"""
+        """adds solution to cache returns whether an improvement was made"""
         tile_cache = self.cache[step.row][step.col]
         existing_item = tile_cache[step.direction, step.consecutive_steps]
         if existing_item is None:
             tile_cache[step.direction, step.consecutive_steps] = step
             return True
 
+        # due to the way that we run in BFS, we shouldn't be getting
+        # into this branch
         if step.total_cost < existing_item.total_cost:
-            tile_cache[step.direction, step.consecutive_steps] = step
-            return True
+            raise AssertionError("this shouldn't be possible")
+            # tile_cache[step.direction, step.consecutive_steps] = step
+            # return True
         return False
 
 
@@ -114,7 +117,7 @@ def solve(self) -> Step:
                 if (new_step := self.create_step(step, direction)) is not None:
                     steps_to_explore.put(new_step)
 
-        raise ValueError("No solution found!")
+        raise AssertionError("No solution found!")
 
     def is_oob(self, row: int, col: int) -> bool:
         """true if laser is out of bounds"""
@@ -169,4 +172,4 @@ def solve(self) -> Step:
             for direction in ALL_DIRECTIONS:
                 if (new_step := self.create_step(step, direction)) is not None:
                     steps_to_explore.put(new_step)
-        raise ValueError("No solution found!")
+        raise AssertionError("No solution found!")

day17/lib/direction.py

@@ -21,7 +21,7 @@ def __str__(self) -> str:
             return "v"
         elif self == Direction.WEST:
             return "<"
-        raise ValueError("invalid value")
+        raise AssertionError("invalid value")
 
     def opposite(self) -> "Direction":
         int_value = int(self)
@@ -36,7 +36,7 @@ def offset(self, row: int, col: int) -> tuple[int, int]:
             return (row + 1, col)
         if self == Direction.WEST:
             return (row, col - 1)
-        raise ValueError("direction not suppported", self)
+        raise AssertionError("direction not suppported", self)
 
     def offset_list(self, row: int, col: int, size: int = 4) -> list[tuple[int, int]]:
         offsets = range(1, size + 1)
@@ -48,7 +48,7 @@ def offset_list(self, row: int, col: int, size: int = 4) -> list[tuple[int, int]
             return [(row + i, col) for i in offsets]
         if self == Direction.WEST:
             return [(row, col - i) for i in offsets]
-        raise ValueError("direction not suppported", self)
+        raise AssertionError("direction not suppported", self)
 
 
 ALL_DIRECTIONS = list(Direction)