Unpacking multiple levels can be specified by an optional argument of @…

…unpack and @unpackall

This is just proof of concept. Documentation has not been updated.

ddt.py

@@ -37,7 +37,7 @@
 # Public interface - Decorators
 
 
-def unpack(func):
+def unpack(arg):
     """
     Method decorator to unpack parameters from the next (syntactically)
     parameters set (``@data`` or ``@file_data`` decorator) by one level.
@@ -46,19 +46,33 @@ def unpack(func):
     and/or applied multiple times.
 
     """
-    getattr(func, PARAMS_SETS_ATTR)[0].unpack()
+    if isinstance(arg, int):
+        return lambda func: _unpack(arg, func)
+    else:
+        return _unpack(1, arg)
+
+
+def _unpack(count, func):
+    getattr(func, PARAMS_SETS_ATTR)[0].unpack(count)
     return func
 
 
-def unpackall(func):
+def unpackall(arg):
     """
     Method decorator to unpack parameters in all parameter sets by one level.
 
     Multiple levels are unpacked if ``@unpack`` and ``@unpackall`` are combined
     and/or applied multiple times.
 
     """
-    setattr(func, UNPACKALL_ATTR, getattr(func, UNPACKALL_ATTR, 0) + 1)
+    if isinstance(arg, int):
+        return lambda func: _unpackall(arg, func)
+    else:
+        return _unpackall(1, arg)
+
+
+def _unpackall(count, func):
+    setattr(func, UNPACKALL_ATTR, getattr(func, UNPACKALL_ATTR, 0) + count)
     return func
 
 
@@ -309,15 +323,15 @@ def __init__(self, *unnamed_values, **named_values):
         self.unnamed_values = unnamed_values
         self.named_values = named_values
 
-    def unpack(self):
+    def unpack(self, count=1):
         """
         Increases by one the number of times values should be unpacked before
         passing them to the test function.
 
         This method is called directly by the ``unpack`` decorator.
 
         """
-        self.unpack_count = self.unpack_count + 1
+        self.unpack_count = self.unpack_count + count
 
     def use_class(self, cls):  # pylint: disable=unused-argument
         """
@@ -381,15 +395,15 @@ def use_class(self, cls):
         self.pathbase = os.path.dirname(cls_path)
         return self
 
-    def unpack(self):
+    def unpack(self, count=1):
         """
         Increase by one the number of times values should be unpacked before
         passing them to the test function.
 
         This method is called directly by the @unpack decorator.
 
         """
-        self.unpack_count = self.unpack_count + 1
+        self.unpack_count = self.unpack_count + count
 
     def load_values(self):  # pylint: disable=unused-argument
         try:

test/test_ddt2_specification.py

@@ -512,3 +512,37 @@ def test(self, *args, **kwargs):
 
         method_name = 'test__0_u0158' if six.PY2 else 'test__0_\u0158'
         self.assertTrue(hasattr(tc, method_name))
+
+    def test__multi_level_unpack_by_decorator_argument(self):
+
+        @ddt.ddt
+        class SampleTestCase(object):
+            @ddt.data(A=['a', 'b'])
+            @ddt.unpack(2)
+            @ddt.data(B=[('c', 'd')])
+            @ddt.data(C=dict(x='e', y='f'))
+            def test(self, *args, **kwargs):
+                return args, kwargs
+
+        tc = SampleTestCase()
+
+        args, kwargs = tc.test__0_A__0_B__0_C()
+        self.assertEqual(args, (['a', 'b'], 'c', 'd', dict(x='e', y='f')))
+        self.assertEqual(kwargs, {})
+
+    def test__multi_level_unpackall_by_decorator_argument(self):
+
+        @ddt.ddt
+        class SampleTestCase(object):
+            @ddt.unpackall(2)
+            @ddt.data(A=['a', 'b'])
+            @ddt.data(B=[('c', 'd')])
+            @ddt.data(C=dict(x='e', y='f'))
+            def test(self, *args, **kwargs):
+                return args, kwargs
+
+        tc = SampleTestCase()
+
+        args, kwargs = tc.test__0_A__0_B__0_C()
+        self.assertEqual(args, ('a', 'b', 'c', 'd'))
+        self.assertEqual(kwargs, dict(x='e', y='f'))