Create hash method for QgsPoint (Fix #8775)

m-kuhn · m-kuhn · commit 44b7767134e4 · 2013-10-12T12:26:10.000+02:00
diff --git a/python/core/qgspoint.sip b/python/core/qgspoint.sip
@@ -126,4 +126,9 @@ class QgsPoint
         PyErr_SetString(PyExc_IndexError, msg.toAscii().constData());
     }
 %End
+
+  long __hash__() const;
+%MethodCode
+  sipRes = qHash( *sipCpp );
+%End
 }; // class QgsPoint
diff --git a/src/core/qgspoint.h b/src/core/qgspoint.h
@@ -193,6 +193,7 @@ class CORE_EXPORT QgsPoint
     //! y coordinate
     double m_y;
 
+    friend uint qHash( const QgsPoint& pnt );
 
 }; // class QgsPoint
 
@@ -212,4 +213,13 @@ inline std::ostream& operator << ( std::ostream& os, const QgsPoint &p )
   return os;
 }
 
+inline uint qHash( const QgsPoint& p )
+{
+  uint hash;
+  uint h1 = qHash(( quint64 )p.m_x );
+  uint h2 = qHash(( quint64 )p.m_y );
+  hash = h1 ^( h2 << 1 );
+  return hash;
+}
+
 #endif //QGSPOINT_H
diff --git a/tests/src/python/test_qgspoint.py b/tests/src/python/test_qgspoint.py
@@ -49,6 +49,17 @@ def test_pointToString(self):
         myMessage = 'Expected: %s Got: %s' % (myExpectedValue, myActualValue)
         assert myExpectedValue == myActualValue, myMessage
 
+    def test_hash(self):
+        a = QgsPoint( 2.0, 1.0 )
+        b = QgsPoint( 2.0, 2.0 )
+        c = QgsPoint( 1.0, 2.0 )
+        d = QgsPoint( 1.0, 1.0 )
+        e = QgsPoint( 2.0, 1.0 )
+        assert a.__hash__() != b.__hash__()
+        assert e.__hash__() == a.__hash__()
+
+        mySet = set( [ a, b, c, d, e ] )
+        assert len( mySet ) == 4
 
 if __name__ == '__main__':
     unittest.main()
