Reveals the bug

Author: aaltat

atest/DynamicTypesAnnotationsLibrary.py

@@ -148,3 +148,7 @@ def enum_conversion(self, param: Optional[penum] = None):
     def keyword_with_deco_and_signature(self, arg1: bool = False, arg2: bool = False):
         """Test me doc here"""
         return f"{arg1}: {type(arg1)}, {arg2}: {type(arg2)}"
+
+    @keyword
+    def keyword_optional_with_none(self, arg: Optional[str] = None):
+        return f"arg: {arg}, type: {type(arg)}"

atest/tests_types.robot

@@ -1,5 +1,6 @@
 *** Settings ***
 Library        DynamicTypesLibrary.py
+Library        DynamicTypesAnnotationsLibrary.py    xxx
 Suite Setup    Import DynamicTypesAnnotationsLibrary In Python 3 Only
 
 *** Test Cases ***
@@ -73,6 +74,16 @@ Enum Conversion To Invalid Value Should Fail
     Run Keyword And Expect Error    ValueError: Argument 'param' got value 'not ok' that*
     ...    Enum Conversion    not ok
 
+Type Conversion With Optional And None
+    ${types} =    Keyword Optional With None
+    Should Contain    ${types}    arg: None,
+    Should Contain    ${types}    <class 'NoneType'>
+    ${types} =    Keyword Optional With None    None
+    Should Contain    ${types}    arg: None,
+    Should Contain    ${types}    <class 'str'>
+    ${types} =    Keyword Optional With None    ${None}
+    Should Contain    ${types}    arg: None,
+    Should Contain    ${types}    <class 'NoneType'>
 
 *** Keywords ***
 Import DynamicTypesAnnotationsLibrary In Python 3 Only

utest/test_get_keyword_types.py

@@ -180,3 +180,8 @@ def test_keyword_self_and_keyword_only_types(lib_types):
 def test_keyword_with_decorator_arguments(lib_types):
     types = lib_types.get_keyword_types('keyword_with_deco_and_signature')
     assert types == {'arg1': bool, 'arg2': bool}
+
+
+def test_keyword_optional_with_none_1(lib_types):
+    types = lib_types.get_keyword_types('keyword_optional_with_none')
+    assert types == {'arg': Union[str, type(None)]}