Python: Add some confusing (but valid) property tests

python/ql/test/library-tests/descriptors/Methods.expected

@@ -1,6 +1,6 @@
-| 55 | classmethod() | 56 | Function c1 |
-| 62 | classmethod() | 59 | Function c2 |
-| 63 | classmethod() | 59 | Function c2 |
-| 65 | staticmethod() | 66 | Function s1 |
-| 72 | staticmethod() | 69 | Function s2 |
-| 73 | staticmethod() | 69 | Function s2 |
+| 104 | classmethod() | 105 | Function c1 |
+| 111 | classmethod() | 108 | Function c2 |
+| 112 | classmethod() | 108 | Function c2 |
+| 114 | staticmethod() | 115 | Function s1 |
+| 121 | staticmethod() | 118 | Function s2 |
+| 122 | staticmethod() | 118 | Function s2 |

python/ql/test/library-tests/descriptors/test.py

@@ -43,6 +43,13 @@ class WithoutDecoratorOnlyGetter(object):
 
     x = property(getx)
 
+class WithoutDecoratorOnlyGetterKWArg(object):
+
+    def getx(self):
+        return 42
+
+    x = property(fget=getx)
+
 class WithoutDecoratorOnlySetter(object):
 
     def setx(self, value):
@@ -50,6 +57,48 @@ class WithoutDecoratorOnlySetter(object):
 
     x = property(fset=setx) # TODO: Not handled
 
+class WithDecoratorOnlySetter(object):
+
+    x = property()
+
+    @x.setter
+    def x(self, value):
+        print('{} setting value to {}'.format(self.__class__, value))
+
+class FunkyButValid(object):
+
+    def delx(self):
+        print("deleting x")
+
+    x = property(fdel=delx)
+
+    @x.setter
+    def y(self, value):
+        print('setting value to {}'.format(value))
+
+    @y.getter
+    def z(self):
+        return 42
+
+
+wat = FunkyButValid()
+try:
+    wat.x
+except AttributeError as e:
+    print("x can't be read")
+del wat.x
+
+try:
+    wat.y
+except AttributeError as e:
+    print("y can't be read")
+wat.y = 1234
+del wat.y
+
+print(wat.z)
+wat.z = 10
+del wat.z
+
 class D(object):
 
     @classmethod