+# Check that moving line A does not affect lines
+#=========================================================================
+aSession.startOperation()
+aLineAEndPoint.setValue(90., 0.)
+aSession.finishOperation()
+# Check that constarint keep features' values
+assert ((aLineAStartPoint.x(), aLineAStartPoint.y()) == (aLineCEndPoint.x(), aLineCEndPoint.y()))
+assert ((aLineBStartPoint.x(), aLineBStartPoint.y()) == (aLineAEndPoint.x(), aLineAEndPoint.y()))
+assert ((aLineCStartPoint.x(), aLineCStartPoint.y()) == (aLineBEndPoint.x(), aLineBEndPoint.y()))
+#=========================================================================
+# Check that moving line B does not affect lines