flow.Filter gets representation, equality and unequality operators.

lena/flow/filter.py

@@ -56,3 +56,14 @@ def run(self, flow):
         # for val in flow:
         #     if self._selector(val):
         #         yield event
+
+    def __eq__(self, other):
+        if isinstance(other, Filter):
+            return self._selector == other._selector
+        return NotImplemented
+
+    def __ne__(self, other):
+        return not (self == other)
+
+    def __repr__(self):
+        return "Filter({})".format(repr(self._selector))

tests/flow/test_filter.py

@@ -39,3 +39,11 @@ def test_filter():
     data3 = [histogram([1, 2])]
     f3 = Filter(histogram)
     assert list(f3.run(data3)) == data3
+
+    # representation works
+    assert repr(f3) == "Filter(Selector(histogram))"
+
+    # equality works
+    f4 = Filter(fun)
+    assert f4 == f2
+    assert f3 != f4