Add contents_near() spatial query to Zone

src/mudlib/zone.py

@@ -67,3 +67,37 @@ class Zone(Object):
     def contents_at(self, x: int, y: int) -> list[Object]:
         """Return all contents at the given coordinates."""
         return [obj for obj in self._contents if obj.x == x and obj.y == y]
+
+    def contents_near(self, x: int, y: int, range_: int) -> list[Object]:
+        """Return all contents within range_ tiles of (x, y).
+
+        Uses wrapping-aware Manhattan distance for toroidal zones.
+        Includes objects at exactly (x, y).
+
+        Args:
+            x: X coordinate of center point
+            y: Y coordinate of center point
+            range_: Maximum Manhattan distance (inclusive)
+
+        Returns:
+            List of all objects within range
+        """
+        nearby = []
+        for obj in self._contents:
+            # Skip objects without coordinates
+            if obj.x is None or obj.y is None:
+                continue
+
+            dx_dist = abs(obj.x - x)
+            dy_dist = abs(obj.y - y)
+
+            if self.toroidal:
+                # Use wrapping-aware distance
+                dx_dist = min(dx_dist, self.width - dx_dist)
+                dy_dist = min(dy_dist, self.height - dy_dist)
+
+            manhattan_dist = dx_dist + dy_dist
+            if manhattan_dist <= range_:
+                nearby.append(obj)
+
+        return nearby

tests/test_zone.py

@@ -200,3 +200,82 @@ def test_contents_at_multiple():
     assert rock in result
     assert gem in result
     assert len(result) == 2
+
+
+# --- contents_near ---
+
+
+def test_contents_near_empty():
+    """contents_near returns empty list when nothing nearby."""
+    terrain = [["." for _ in range(10)] for _ in range(10)]
+    zone = Zone(name="test", width=10, height=10, terrain=terrain)
+    assert zone.contents_near(5, 5, 3) == []
+
+
+def test_contents_near_includes_exact_position():
+    """contents_near includes objects at the exact coordinates."""
+    terrain = [["." for _ in range(10)] for _ in range(10)]
+    zone = Zone(name="test", width=10, height=10, terrain=terrain)
+    obj = Object(name="rock", location=zone, x=5, y=5)
+    result = zone.contents_near(5, 5, 3)
+    assert obj in result
+
+
+def test_contents_near_within_range():
+    """contents_near returns objects within Manhattan distance range."""
+    terrain = [["." for _ in range(20)] for _ in range(20)]
+    zone = Zone(name="test", width=20, height=20, terrain=terrain)
+    center = Object(name="center", location=zone, x=10, y=10)
+    nearby1 = Object(name="nearby1", location=zone, x=11, y=10)  # distance 1
+    nearby2 = Object(name="nearby2", location=zone, x=10, y=12)  # distance 2
+    nearby3 = Object(name="nearby3", location=zone, x=12, y=12)  # distance 4
+    far = Object(name="far", location=zone, x=15, y=15)  # distance 10
+
+    result = zone.contents_near(10, 10, 3)
+    assert center in result
+    assert nearby1 in result
+    assert nearby2 in result
+    assert nearby3 not in result  # distance 4 > range 3
+    assert far not in result
+
+
+def test_contents_near_wrapping_toroidal():
+    """contents_near uses wrapping-aware distance on toroidal zones."""
+    terrain = [["." for _ in range(10)] for _ in range(10)]
+    zone = Zone(name="test", width=10, height=10, terrain=terrain, toroidal=True)
+    # Object at (1, 1), query at (9, 9)
+    # Without wrapping: dx=8, dy=8
+    # With wrapping: dx=min(8, 10-8)=2, dy=min(8, 10-8)=2, total=4
+    obj = Object(name="wrapped", location=zone, x=1, y=1)
+    result = zone.contents_near(9, 9, 5)
+    assert obj in result  # within range due to wrapping
+
+    result_tight = zone.contents_near(9, 9, 3)
+    assert obj not in result_tight  # outside tighter range
+
+
+def test_contents_near_no_wrapping_bounded():
+    """contents_near uses straight distance on bounded zones."""
+    terrain = [["." for _ in range(10)] for _ in range(10)]
+    zone = Zone(name="test", width=10, height=10, terrain=terrain, toroidal=False)
+    # Object at (1, 1), query at (9, 9)
+    # Straight distance: dx=8, dy=8, total=16
+    obj = Object(name="far", location=zone, x=1, y=1)
+    result = zone.contents_near(9, 9, 5)
+    assert obj not in result  # too far on bounded zone
+
+
+def test_contents_near_multiple():
+    """contents_near returns all objects within range."""
+    terrain = [["." for _ in range(20)] for _ in range(20)]
+    zone = Zone(name="test", width=20, height=20, terrain=terrain)
+    obj1 = Object(name="obj1", location=zone, x=10, y=10)
+    obj2 = Object(name="obj2", location=zone, x=11, y=10)
+    obj3 = Object(name="obj3", location=zone, x=10, y=11)
+    Object(name="far", location=zone, x=20, y=20)  # far away
+
+    result = zone.contents_near(10, 10, 2)
+    assert len(result) == 3
+    assert obj1 in result
+    assert obj2 in result
+    assert obj3 in result