Cleaner handling for unsupported type annotation

    * In preparation for #8

simplecli/simplecli.py

@@ -42,6 +42,10 @@ class DefaultIfBool:
     pass
 
 
+class UnsupportedType(TypeError):
+    pass
+
+
 _wrapped = False
 ValueType = Union[type[DefaultIfBool], type[Empty], bool, float, int, str]
 ArgDict = dict[str, ValueType]
@@ -65,14 +69,6 @@ def __init__(self, *argv: Any, **kwargs: Any) -> None:
                 raise TypeError("needs 'name' argument")
             kwargs["name"] = argv[0]
             argv = ()
-        if kwargs["annotation"] not in get_args(ValueType):
-            if get_origin(kwargs["annotation"]) not in (Union, UnionType):
-                if kwargs["annotation"] is not Empty:
-                    raise ValueError(
-                        "annotation type "
-                        f"'{type(kwargs['annotation']).__name__}' "
-                        "is not currently supported!"
-                    )
         param_description = str(kwargs.pop("description", ""))
         param_line = str(kwargs.pop("line", ""))
         param_value = kwargs.pop("value", Empty)
@@ -90,6 +86,16 @@ def __init__(self, *argv: Any, **kwargs: Any) -> None:
         # Overrides required as these values are generally unused
         if not self.description:
             self.parse_or_prepend(param_line)
+        annotation = kwargs["annotation"]
+        if annotation not in get_args(ValueType):
+            if get_origin(annotation) not in (Union, UnionType):
+                if annotation is not Empty:
+                    pretty_annotation = (
+                        annotation
+                        if type(annotation) is type
+                        else annotation.__class__.__name__
+                    )
+                    raise UnsupportedType(kwargs["name"], pretty_annotation)
 
     def __eq__(self, other: object) -> bool:
         if not isinstance(other, Param):
@@ -376,7 +382,21 @@ def wrap(func: Callable[..., Any]) -> Callable[..., Any]:
     _wrapped = True
     filename = sys.argv[0]
     argv = sys.argv[1:]
-    params = extract_code_params(code=func)
+    try:
+        params = extract_code_params(code=func)
+    except UnsupportedType as e:
+        source = inspect.findsource(func)
+        offset = source[1] + 1
+        offset += [
+            index
+            for index, line in enumerate(source[0][source[1] :])
+            if re.search(rf"[\(\s]{e.args[0]}:", line)
+        ][0]
+        exit(
+            f"File {'"' + filename + '"'}, line {offset}\n"
+            f"{source[0][offset - 1].rstrip()}\n"
+            f"UnsupportedType: {e.args[1]}"
+        )
     pos_args, kw_args = clean_args(argv)
     params.append(
         Param("help", description="Show this message", internal_only=True)

tests/test_param.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 import pytest
 import re
-from simplecli.simplecli import DefaultIfBool, Empty, Param
+from simplecli.simplecli import DefaultIfBool, Empty, Param, UnsupportedType
 from tests.utils import skip_if_uniontype_unsupported
 from typing import Optional, Union
 
@@ -92,7 +92,7 @@ def test_set_value():
     p2 = Param(name="testparam2", annotation=bool, default=True)
     assert p2.value is True
 
-    with pytest.raises(ValueError, match="list"):
+    with pytest.raises(UnsupportedType, match="list"):
         Param(name="testparam3", annotation=[str, bool])
 
     p3 = Param(name="testparam3", annotation=str)

tests/test_wrap.py

@@ -266,3 +266,14 @@ def code1(foo):
     with pytest.raises(SystemExit, match="function parameters need type"):
         code1.__globals__["__name__"] = "__main__"
         simplecli.wrap(code1)
+
+
+def test_wrap_unsupported_type(monkeypatch):
+    monkeypatch.setattr(sys, "argv", ["filename", "--foo"])
+
+    def code1(foo: [str, int]):
+        pass
+
+    with pytest.raises(SystemExit, match="UnsupportedType: list"):
+        code1.__globals__["__name__"] = "__main__"
+        simplecli.wrap(code1)