Add get_docval_macro method (#446)

* Add get_docval_macro method

* Update changelog

* Update get_docval_macro, add 'data' to macros

* Update test

CHANGELOG.md

@@ -9,6 +9,8 @@
 - Add support for creating and specifying multi-index columns in a `DynamicTable` using `add_column(...)`.
   @bendichter, @rly (#430)
 - Add capability to add a row to a column after IO. @bendichter (#426)
+- Add method `hdmf.utils.get_docval_macro` to get a tuple of the current values for a docval_macro, e.g., 'array_data'  
+  and 'scalar_data'. @rly (#456)
 
 ### Internal improvements
 - Refactor `HDF5IO.write_dataset` to be more readable. @rly (#428)

src/hdmf/utils.py

@@ -10,6 +10,7 @@
 __macros = {
     'array_data': [np.ndarray, list, tuple, h5py.Dataset],
     'scalar_data': [str, int, float, bytes],
+    'data': []
 }
 
 # code to signify how to handle positional arguments in docval
@@ -41,6 +42,19 @@ def _dec(cls):
     return _dec
 
 
+def get_docval_macro(key=None):
+    """
+    Return a deepcopy of the docval macros, i.e., strings that represent a customizable list of types for use in docval.
+
+    :param key: Name of the macro. If key=None, then a dictionary of all macros is returned. Otherwise, a tuple of
+                the types associated with the key is returned.
+    """
+    if key is None:
+        return _copy.deepcopy(__macros)
+    else:
+        return tuple(__macros[key])
+
+
 def __type_okay(value, argtype, allow_none=False):
     """Check a value against a type
 

tests/unit/utils_test/test_docval.py

@@ -1,6 +1,7 @@
 import numpy as np
 
-from hdmf.utils import docval, fmt_docval_args, get_docval, getargs, popargs, AllowPositional
+from hdmf.utils import (docval, fmt_docval_args, get_docval, getargs, popargs, AllowPositional, get_docval_macro,
+                        docval_macro)
 from hdmf.testing import TestCase
 
 
@@ -968,3 +969,24 @@ def test_arg_not_found_many_args(self):
         msg = "Argument not found in dict: 'c'"
         with self.assertRaisesWith(ValueError, msg):
             popargs('a', 'c', kwargs)
+
+
+class TestMacro(TestCase):
+
+    def test_macro(self):
+        self.assertTrue(isinstance(get_docval_macro(), dict))
+        self.assertSetEqual(set(get_docval_macro().keys()), {'array_data', 'scalar_data', 'data'})
+
+        self.assertTupleEqual(get_docval_macro('scalar_data'), (str, int, float, bytes))
+
+        @docval_macro('scalar_data')
+        class Dummy1:
+            pass
+
+        self.assertTupleEqual(get_docval_macro('scalar_data'), (str, int, float, bytes, Dummy1))
+
+        @docval_macro('dummy')
+        class Dummy2:
+            pass
+
+        self.assertTupleEqual(get_docval_macro('dummy'), (Dummy2, ))