implement BDD osm2pgsql tests with pytest-bdd

test/bdd/utils/grid.py

@@ -0,0 +1,34 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2025 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+A grid describing node placement in an area.
+Useful for visually describing geometries.
+"""
+
+
+class Grid:
+
+    def __init__(self, table, step, origin):
+        if step is None:
+            step = 0.00001
+        if origin is None:
+            origin = (0.0, 0.0)
+        self.grid = {}
+
+        y = origin[1]
+        for line in table:
+            x = origin[0]
+            for pt_id in line:
+                if pt_id:
+                    self.grid[pt_id] = (x, y)
+                x += step
+            y += step
+
+    def get(self, nodeid):
+        """ Get the coordinates for the given grid node.
+        """
+        return self.grid.get(nodeid)