[processing] Update the comparison implementation in voronoi.py (fixes #18219)

havatv · nyalldawson · commit ca0017410b84 · 2018-08-08T04:48:26.000+10:00
When "translating" the cmp function of Site and Halfedge to Python 3, the __lt__ function was forgotten.  It has been added.
diff --git a/python/plugins/processing/algs/qgis/voronoi.py b/python/plugins/processing/algs/qgis/voronoi.py
@@ -397,7 +397,7 @@ def __lt__(self, other):
             return False
         elif self.x < other.x:
             return True
-        elif self.x > other.x:
+        else:
             return False
 
     def distance(self, other):
@@ -512,7 +512,7 @@ def __lt__(self, other):
             return False
         elif self.vertex.x < other.vertex.x:
             return True
-        elif self.vertex.x > other.vertex.x:
+        else:
             return False
 
     def leftreg(self, default):
@@ -905,4 +905,4 @@ def cmp(a, b):
 
     In python 2 cmp() was a built in function but in python 3 is gone.
     """
-    return (a > b) - (a < b)
+    return (b < a) - (a < b)
