Test default value case for RepresentationMixin (#3923)

Parameters with default values take a different path in
RepresentationMixin and that path was previously not tested.

# Changed Behaviour

none

## Type of change

- Code maintenance/cleanup

Author: benclifford

parsl/tests/test_utils/test_representation_mixin.py

@@ -9,6 +9,12 @@ def __init__(self, x, y):
         self.y = y
 
 
+class GoodReprDefaults(RepresentationMixin):
+    def __init__(self, x, y="default 2"):
+        self.x = x
+        self.y = y
+
+
 class BadRepr(RepresentationMixin):
     """This class incorrectly subclasses RepresentationMixin.
     It does not store the parameter x on self.
@@ -31,6 +37,33 @@ def test_repr_good():
     assert p2 in r
 
 
+@pytest.mark.local
+def test_repr_good_defaults_overridden():
+    p1 = "parameter 1"
+    p2 = "the second parameter"
+
+    # repr should not raise an exception
+    r = repr(GoodReprDefaults(p1, p2))
+
+    # representation should contain both values supplied
+    # at object creation.
+    assert p1 in r
+    assert p2 in r
+
+
+@pytest.mark.local
+def test_repr_good_defaults_defaulted():
+    p1 = "parameter 1"
+
+    # repr should not raise an exception
+    r = repr(GoodReprDefaults(p1))
+
+    # representation should contain one value supplied
+    # at object creation, and the other defaulted.
+    assert p1 in r
+    assert "default 2" in r
+
+
 @pytest.mark.local
 def test_repr_bad():
     p1 = "parameter 1"