diff --git a/tests/unit/processing/test_builtin.py b/tests/unit/processing/test_builtin.py
index a7bae37..9172567 100644
--- a/tests/unit/processing/test_builtin.py
+++ b/tests/unit/processing/test_builtin.py
@@ -234,12 +234,9 @@ def test_process_typing() -> None:
     flat_config = Config(flat_dict, [processing])
     flat_config = processing.premerge(flat_config)
     flat_config.dict["param1"] = 3
-    flat_config.dict["param2"] = {"a": None, "b": [{"c": 1}]}
-    flat_config.dict = flatten(flat_config.dict)
+    flat_config.dict["param2"] = [None, {"b": 1, "c": 2.1}]
     flat_config = processing.postmerge(flat_config)
-    check.equal(
-        flat_config.dict, {"param1": 3, "param2.a": None, "param2.b": [{"c": 1}]}
-    )
+    check.equal(flat_config.dict, {"param1": 3, "param2": [None, {"b": 1, "c": 2.1}]})
     check.equal(
         flat_config.process_list[0].forced_types,  # type: ignore
         {
@@ -252,10 +249,18 @@ def test_process_typing() -> None:
         {"param1": "int", "param2": "List[Optional[Dict[str, int|float]]]"},
     )
     flat_config = processing.endbuild(flat_config)  # no error
+    flat_config.dict["param1"] = "3"
+    flat_config.dict["param2"] = [{"d": "2.3"}, None]
+    flat_config = processing.endbuild(flat_config)  # no error
+    check.equal(flat_config.dict["param1"], 3)
+    check.equal(flat_config.dict["param2"], [{"d": 2.3}, None])
     flat_config = processing.presave(flat_config)
     check.equal(
         flat_config.dict,
-        {"param1@type:int": 3, "param2.a": None, "param2.b": [{"c": 1}]},
+        {
+            "param1@type:int": 3,
+            "param2@type:List[Optional[Dict[str, int|float]]]": [{"d": 2.3}, None],
+        },
     )
     processing.forced_types = {}  # Reset forced types
     processing.type_desc = {}  # Reset type description
diff --git a/tests/unit/processing/test_type_parser.py b/tests/unit/processing/test_type_parser.py
index 432ecd7..3413bec 100644
--- a/tests/unit/processing/test_type_parser.py
+++ b/tests/unit/processing/test_type_parser.py
@@ -5,6 +5,7 @@
 import pytest_check as check
 
 from cliconfig.processing._type_parser import (
+    _convert_type,
     _isinstance,
     _parse_dict,
     _parse_list,
@@ -14,24 +15,30 @@
 )
 
 
-def test_type_parser_isinstance() -> None:
-    """Test _parse_type and _isinstance."""
+def test_type_routines() -> None:
+    """Test _parse_type, _isinstance and _convert_type."""
     type_ = _parse_type("None")
     check.equal(type_, (type(None),))
     check.is_true(_isinstance(None, type_))
     check.is_false(_isinstance([None], type_))
+    check.equal(_convert_type("unchanged", type_), "unchanged")
 
     type_ = _parse_type("List[float]")
     check.equal(type_, (("list", (float,)),))
 
-    type_ = _parse_type("list|dict")
-    check.equal(type_, (list, dict))
+    type_ = _parse_type("dict|list")
+    check.equal(type_, (dict, list))
     check.is_true(_isinstance([2.0, True], type_))
+    check.equal(_convert_type((0, 1), type_), [0, 1])
 
     type_ = _parse_type("Dict[str, List[float]]")
     check.equal(type_, (("dict", (str,), (("list", (float,)),)),))
     check.is_true(_isinstance({"a": [1.0, 2.0]}, type_))
     check.is_false(_isinstance({"a": [1.0, 2.0], "b": [1.0, 2]}, type_))
+    check.equal(
+        _convert_type({"a": [1.0, 2.0], "b": [1.0, 2]}, type_),
+        {"a": [1.0, 2.0], "b": [1.0, 2.0]},
+    )
 
     type_ = _parse_type("Dict[str|bool, int|float]")
     check.equal(type_, (("dict", (str, bool), (int, float)),))
@@ -65,7 +72,15 @@ def test_type_parser_isinstance() -> None:
     check.is_true(_isinstance({1: {"a": 2.0}}, type_))
     check.is_false(_isinstance({"a": [None, 1.0], "b": {False: 1, True: "1"}}, type_))
 
+    type_ = _parse_type("Dict[int, Optional[Dict[str, float]]]")
+    check.equal(
+        _convert_type({"0": {1: True, 2: "2.3"}, "1": {3: 3, 4: 4}}, type_),
+        {0: {"1": 1.0, "2": 2.3}, 1: {"3": 3.0, "4": 4.0}},
+    )
+    check.equal(_convert_type({"str": None}, type_), {"str": None})
+
     # Wrong type description
+    check.equal(_convert_type({"str": None}, ("list")), {"str": None})  # type: ignore
     with pytest.raises(ValueError, match="Unknown type: 'unknown'"):
         _parse_type("unknown")
     desc = "str, List[float]"