Merge pull request #37 from fwfurtado/issue-29

Added supporting to type hint in curried decorator

fn/func.py

@@ -1,5 +1,8 @@
 from functools import partial, update_wrapper, wraps
-from inspect import getargspec
+from sys import version_info
+
+
+_has_type_hint_support = version_info[:2] >= (3, 5)
 
 
 def identity(arg):
@@ -69,6 +72,17 @@ def curried(func):
     >>> sum5(1, 2, 3)(4, 5)
     15
     """
+
+    def _args_len(func):
+        if _has_type_hint_support:
+            from inspect import signature
+            args = signature(func).parameters
+        else:
+            from inspect import getargspec
+            args = getargspec(func).args
+
+        return len(args)
+
     @wraps(func)
     def _curried(*args, **kwargs):
         f = func
@@ -78,9 +92,7 @@ def _curried(*args, **kwargs):
                 count += len(f.args)
             f = f.func
 
-        spec = getargspec(f)
-
-        if count == len(spec.args) - len(args):
+        if count == _args_len(f) - len(args):
             return func(*args, **kwargs)
 
         para_func = partial(func, *args, **kwargs)

fn/monad.py

@@ -48,9 +48,9 @@ def parameter(self, name):
     from fn.monad import Option
 
     request = dict(url="face.png", mimetype="PNG")
-    tp = Option(request.get("type", None)) \ # check "type" key first
-      .or_call(from_mimetype, request) \ # or.. check "mimetype" key
-      .or_call(from_extension, request) \ # or... get "url" and check extension
+    tp = Option(request.get("type", None)) \\ # check "type" key first
+      .or_call(from_mimetype, request) \\ # or... check "mimetype" key
+      .or_call(from_extension, request) \\# or... get "url" and check extension
       .get_or("application/undefined")
 
 """

tests/test_curry.py

@@ -1,10 +1,17 @@
 import unittest
 
-from fn.func import curried
+from fn.func import curried, _has_type_hint_support
 
 
 class Curriedtest(unittest.TestCase):
 
+    def _assert_instance(self, expected, acutal):
+        self.assertEqual(expected.__module__, acutal.__module__)
+        self.assertEqual(expected.__name__, acutal.__name__)
+
+        if _has_type_hint_support:
+            self.assertEqual(expected.__annotations__, acutal.__annotations__)
+
     def test_curried_wrapper(self):
 
         @curried
@@ -15,16 +22,38 @@ def _child(a, b, c, d):
         def _moma(a, b):
             return _child(a, b)
 
-        def _assert_instance(expected, acutal):
-            self.assertEqual(expected.__module__, acutal.__module__)
-            self.assertEqual(expected.__name__, acutal.__name__)
-
         res1 = _moma(1)
-        _assert_instance(_moma, res1)
+        self._assert_instance(_moma, res1)
+        res2 = res1(2)
+        self._assert_instance(_child, res2)
+        res3 = res2(3)
+        self._assert_instance(_child, res3)
+        res4 = res3(4)
+
+        self.assertEqual(res4, 10)
+
+    @unittest.skipIf(not _has_type_hint_support, "Type hint aren't supported")
+    def test_curried_with_annotations_when_they_are_supported(self):
+
+        def _custom_sum(a, b, c, d):
+            return a + b + c + d
+
+        _custom_sum.__annotations__ = {
+                                        'a': int,
+                                        'b': int,
+                                        'c': int,
+                                        'd': int,
+                                        'return': int
+                                      }
+
+        custom_sum = curried(_custom_sum)
+
+        res1 = custom_sum(1)
+        self._assert_instance(custom_sum, res1)
         res2 = res1(2)
-        _assert_instance(_child, res2)
+        self._assert_instance(custom_sum, res2)
         res3 = res2(3)
-        _assert_instance(_child, res3)
+        self._assert_instance(custom_sum, res3)
         res4 = res3(4)
 
         self.assertEqual(res4, 10)