preserve annotations in canned functions

regression test for annotations, keyword-only defaults

Author: minrk

ipyparallel/serialize/canning.py

@@ -194,10 +194,15 @@ def __init__(self, f):
             self.defaults = None
 
         if f.__kwdefaults__:
-            self.kwdefaults = can(f.__kwdefaults__)
+            self.kwdefaults = can_dict(f.__kwdefaults__)
         else:
             self.kwdefaults = None
 
+        if f.__annotations__:
+            self.annotations = can_dict(f.__annotations__)
+        else:
+            self.annotations = None
+
         closure = py3compat.get_closure(f)
         if closure:
             self.closure = tuple(can(cell) for cell in closure)
@@ -225,16 +230,23 @@ def get_object(self, g=None):
             defaults = None
 
         if self.kwdefaults:
-            kwdefaults = uncan(self.kwdefaults)
+            kwdefaults = uncan_dict(self.kwdefaults)
         else:
             kwdefaults = None
+        if self.annotations:
+            annotations = uncan_dict(self.annotations)
+        else:
+            annotations = {}
 
         if self.closure:
             closure = tuple(uncan(cell, g) for cell in self.closure)
         else:
             closure = None
         newFunc = FunctionType(self.code, g, self.__name__, defaults, closure)
-        newFunc.__kwdefaults__ = kwdefaults
+        if kwdefaults:
+            newFunc.__kwdefaults__ = kwdefaults
+        if annotations:
+            newFunc.__annotations__ = annotations
         return newFunc
 
 

ipyparallel/tests/test_canning.py

@@ -21,6 +21,10 @@ def loads(obj):
     return uncan(pickle.loads(obj))
 
 
+def roundtrip(obj):
+    return loads(dumps(obj))
+
+
 def test_no_closure():
     @interactive
     def foo():
@@ -109,3 +113,20 @@ def foo(arg1, arg2, kwarg1, kwarg2):
     loaded.buffers = buffers
     pfoo2 = uncan(loaded)
     assert pfoo2() == partial_foo()
+
+
+def test_keyword_only_arguments():
+    def compute(a, *, b=3):
+        return a * b
+
+    assert compute(2) == 6
+    compute_2 = roundtrip(compute)
+    assert compute_2(2) == 6
+
+
+def test_annotations():
+    def f(a: int):
+        return a
+
+    f2 = roundtrip(f)
+    assert f2.__annotations__ == f.__annotations__