Processing tests: allow topological geometry tests instead of exact tests

This is useful with geometry algorithms when the order of the coordinates of produced
geometries does not need to be exactly the same every time, but the output is still
topologically equivalent.

Author: wonder-sk

python/plugins/processing/tests/AlgorithmsTestBase.py

@@ -283,13 +283,14 @@ def check_results(self, results, context, params, expected):
 
                 compare = expected_result.get('compare', {})
                 pk = expected_result.get('pk', None)
+                topo_equal_check = expected_result.get('topo_equal_check', False)
 
                 if len(expected_lyrs) == 1:
-                    self.assertLayersEqual(expected_lyrs[0], result_lyr, compare=compare, pk=pk)
+                    self.assertLayersEqual(expected_lyrs[0], result_lyr, compare=compare, pk=pk, geometry={'topo_equal_check': topo_equal_check})
                 else:
                     res = False
                     for l in expected_lyrs:
-                        if self.checkLayersEqual(l, result_lyr, compare=compare, pk=pk):
+                        if self.checkLayersEqual(l, result_lyr, compare=compare, pk=pk, geometry={'topo_equal_check': topo_equal_check}):
                             res = True
                             break
                     self.assertTrue(res, 'Could not find matching layer in expected results')
@@ -319,6 +320,7 @@ def check_results(self, results, context, params, expected):
 
 
 class GenericAlgorithmsTest(unittest.TestCase):
+
     """
     General (non-provider specific) algorithm tests
     """

python/testing/__init__.py

@@ -104,6 +104,11 @@ def checkLayersEqual(self, layer_expected, layer_result, use_asserts=False, **kw
         except KeyError:
             precision = 14
 
+        try:
+            topo_equal_check = compare['geometry']['topo_equal_check']
+        except KeyError:
+            topo_equal_check = False
+
         def sort_by_pk_or_fid(f):
             if 'pk' in kwargs and kwargs['pk'] is not None:
                 key = kwargs['pk']
@@ -118,27 +123,13 @@ def sort_by_pk_or_fid(f):
         result_features = sorted(layer_result.getFeatures(request), key=sort_by_pk_or_fid)
 
         for feats in zip(expected_features, result_features):
-            if feats[0].hasGeometry():
-                geom0 = feats[0].geometry().constGet().asWkt(precision)
-            else:
-                geom0 = None
-            if feats[1].hasGeometry():
-                geom1 = feats[1].geometry().constGet().asWkt(precision)
-            else:
-                geom1 = None
-            if use_asserts:
-                _TestCase.assertEqual(
-                    self,
-                    geom0,
-                    geom1,
-                    'Features (Expected fid: {}, Result fid: {}) differ in geometry: \n\n Expected geometry:\n {}\n\n Result geometry:\n {}'.format(
-                        feats[0].id(),
-                        feats[1].id(),
-                        geom0,
-                        geom1
-                    )
-                )
-            elif geom0 != geom1:
+
+            eq = self.checkGeometriesEqual(feats[0].geometry(),
+                                           feats[1].geometry(),
+                                           feats[0].id(),
+                                           feats[1].id(),
+                                           use_asserts, precision, topo_equal_check)
+            if not eq and use_asserts:
                 return False
 
             for attr_expected, field_expected in zip(feats[0].attributes(), layer_expected.fields().toList()):
@@ -215,6 +206,34 @@ def assertFilesEqual(self, filepath_expected, filepath_result):
                 diff = list(diff)
                 self.assertEqual(0, len(diff), ''.join(diff))
 
+    def checkGeometriesEqual(self, geom0, geom1, geom0_id, geom1_id, use_asserts=False, precision=14, topo_equal_check=False):
+        """ Checks whether two geometries are the same - using either a strict check of coordinates (up to given precision)
+        or by using topological equality (where e.g. a polygon with clockwise is equal to a polygon with counter-clockwise
+        order of vertices) """
+        if not geom0.isNull() and not geom1.isNull():
+            if topo_equal_check:
+                equal = geom0.isGeosEqual(geom1)
+            else:
+                equal = geom0.constGet().asWkt(precision) == geom1.constGet().asWkt(precision)
+        elif geom0.isNull() and geom1.isNull():
+            equal = True
+        else:
+            equal = False
+
+        if use_asserts:
+            _TestCase.assertTrue(
+                self,
+                equal,
+                'Features (Expected fid: {}, Result fid: {}) differ in geometry: \n\n Expected geometry:\n {}\n\n Result geometry:\n {}'.format(
+                    geom0_id,
+                    geom1_id,
+                    geom0.constGet().asWkt(precision) if geom0 is not None else 'NULL',
+                    geom1.constGet().asWkt(precision) if geom1 is not None else 'NULL'
+                )
+            )
+        else:
+            return equal
+
 
 class _UnexpectedSuccess(Exception):