Merge branch 'yaramo2' into operations

Author: arneboockmeyer

test/node_test.py

@@ -1,5 +1,8 @@
 from itertools import product
 
+from pytest import raises
+
+from yaramo.geo_node import Wgs84GeoNode
 from yaramo.model import Node
 
 from .helper import create_edge, create_node
@@ -134,3 +137,17 @@ def test_anschluss():
             assert switch.connected_on_right == right, (
                 "right node " f"{coords_str(switch.connected_on_right)} incorrect"
             )
+
+
+def test_implausible_anschluss():
+    """Assert that detection of "Anschluss" (head, left, right) raises
+    an exception on really implausible geographies."""
+    head = create_node(0, 0)  # layout:
+    point = create_node(2, 2)  #      l
+    left = create_node(1, 3)  #       s r
+    right = create_node(3, 2)  #     h
+
+    point.connected_nodes.extend((head, left, right))
+
+    with raises(Exception) as exception:
+        point.calc_anschluss_of_all_nodes()

yaramo/node.py

@@ -155,37 +155,42 @@ def get_anschluss_for_edge(self, edge: "Edge") -> EdgeConnectionDirection:
     def calc_anschluss_of_all_edges(self):
         """Calculates and sets the 'Anschluss' or connection side of
         the connected_nodes based on their geo location."""
-
         if len(self.connected_edges) == 1:
             self.connected_edge_on_head = self.connected_edges[0]
             return
+        almost_zero = sys.float_info.epsilon
 
-        def get_arc_between_geo_nodes(geo_node_a: "GeoNode", geo_node_b: "GeoNode") -> float:
+        def get_rad_between_nodes(geo_node_a: GeoNode, geo_node_b: GeoNode) -> float:
             """
             Returns the angle of an (maybe imaginary) line between
-            :param:`node_a` and :param:`node_b`.
+            :param:`geo_node_a` and :param:`geo_node_b`.
             """
             return atan2(geo_node_b.y - geo_node_a.y, geo_node_b.x - geo_node_a.x)
 
         # Determine which node is head, left, and right by trying the
         # permutations and checking for plausibility.
         for head, left, right in permutations(self.connected_edges):
 
-            head_angle_abs = get_arc_between_geo_nodes(head.get_next_geo_node(self), self.geo_node)
-            left_angle_abs = get_arc_between_geo_nodes(self.geo_node, left.get_next_geo_node(self))
+            head_angle_abs = get_rad_between_nodes(head.get_next_geo_node(self), self.geo_node)
+            left_angle_abs = get_rad_between_nodes(self.geo_node, left.get_next_geo_node(self))
             left_angle_rel = left_angle_abs - head_angle_abs
-            if cos(left_angle_rel) <= sys.float_info.epsilon:
+            if cos(left_angle_rel) <= almost_zero:
                 # left turn more than (or almost) 90°
                 continue
 
-            right_angle_abs = get_arc_between_geo_nodes(
-                self.geo_node, right.get_next_geo_node(self)
-            )
+            right_angle_abs = get_rad_between_nodes(self.geo_node, right.get_next_geo_node(self))
             right_angle_rel = right_angle_abs - head_angle_abs
-            if cos(right_angle_rel) <= sys.float_info.epsilon:
-                # left turn more than (or almost) 90°
+            if cos(right_angle_rel) <= almost_zero:
+                # right turn more than (or almost) 90°
                 continue
 
+            if cos(left_angle_abs - right_angle_abs) <= almost_zero:
+                # turn from left to right less than (or almost) 90°
+                raise Exception(
+                    f"Node {self} has three connected nodes but "
+                    "geometrically, it does not look like a switch."
+                )
+
             if sin(left_angle_rel) < sin(right_angle_rel):
                 # Left and right mixed up. Although the permutations do
                 # contain the correct combination, fixing this right