Implement NewTypedDict and strip TypedDict quals in Attrs/Members

- Add NewTypedDict type and evaluator that creates TypedDicts from
  Member arguments, mirroring NewProtocol
- Strip NotRequired/ReadOnly/Required from type annotations in
  get_annotated_type_hints and move them to quals (Required is
  stripped silently since it's the default)

Author: msullivan

tests/test_ts_utility.py

@@ -70,9 +70,9 @@ class TodoTD(TypedDict):
 # PartialTD<T>
 # Like Partial, but for TypedDicts: wraps all fields in NotRequired
 # rather than making them T | None.
-type PartialTD[T] = typing.NewProtocol[
+type PartialTD[T] = typing.NewTypedDict[
     *[
-        typing.Member[p.name, NotRequired[p.type], p.quals]
+        typing.Member[p.name, p.type, p.quals | Literal["NotRequired"]]
         for p in typing.Iter[typing.Attrs[T]]
     ]
 ]
@@ -112,10 +112,10 @@ class Partial[tests.test_ts_utility.Todo]:
 
 def test_partial_td():
     tgt = eval_typing(PartialTD[TodoTD])
-    fmt = format_helper.format_class(tgt)
-    assert fmt == textwrap.dedent("""\
-        class PartialTD[tests.test_ts_utility.TodoTD]:
-            title: typing.NotRequired[str]
-            description: typing.NotRequired[str]
-            completed: typing.NotRequired[bool]
-    """)
+    assert tgt.__required_keys__ == frozenset()
+    assert tgt.__optional_keys__ == {"title", "description", "completed"}
+    assert tgt.__annotations__ == {
+        "title": NotRequired[str],
+        "description": NotRequired[str],
+        "completed": NotRequired[bool],
+    }

typemap/type_eval/_eval_operators.py

@@ -41,6 +41,7 @@
     Member,
     Members,
     NewProtocol,
+    NewTypedDict,
     Overloaded,
     Param,
     RaiseError,
@@ -116,11 +117,20 @@ def get_annotated_type_hints(cls, *, ctx, attrs_only=False, **kwargs):
         for k, ty in annos.items():
             quals = set()
 
-            # Strip ClassVar/Final from ty and add them to quals
+            # Strip ClassVar/Final/NotRequired/ReadOnly/Required from ty
+            # and add them to quals
             while True:
-                for form in [typing.ClassVar, typing.Final]:
+                for form in [
+                    typing.ClassVar,
+                    typing.Final,
+                    typing.NotRequired,
+                    typing.ReadOnly,
+                    typing.Required,
+                ]:
                     if _typing_inspect.is_special_form(ty, form):
-                        quals.add(form.__name__)
+                        # Required is the default; strip but don't add a qual
+                        if form is not typing.Required:
+                            quals.add(form.__name__)
                         ty = (
                             typing.get_args(ty)[0]
                             if typing.get_args(ty)
@@ -1282,3 +1292,39 @@ def _eval_NewProtocol(*etyps: Member, ctx):
         cls.__init__ = dct['__init__']
 
     return cls
+
+
+def _add_td_quals(typ, quals):
+    for qual in (typing.NotRequired, typing.ReadOnly):
+        if type_eval.issubtype(typing.Literal[qual.__name__], quals):
+            typ = qual[typ]
+    return typ
+
+
+@type_eval.register_evaluator(NewTypedDict)
+@_lift_evaluated
+def _eval_NewTypedDict(*etyps: Member, ctx):
+    annos = {}
+
+    members = [typing.get_args(prop) for prop in etyps]
+    for tname, typ, quals, _init, _ in members:
+        name = _eval_literal(tname, ctx)
+        typ = _eval_types(typ, ctx)
+        tquals = _eval_types(quals, ctx)
+        annos[name] = _add_td_quals(typ, tquals)
+
+    td_name = "NewTypedDict"
+    module_name = __name__
+
+    ctx = type_eval._get_current_context()
+    if ctx.current_generic_alias:
+        if isinstance(ctx.current_generic_alias, types.GenericAlias):
+            td_name = str(ctx.current_generic_alias)
+        else:
+            td_name = f"{ctx.current_generic_alias.__name__}[...]"
+        module_name = ctx.current_generic_alias.__module__
+
+    cls = typing.TypedDict(td_name, annos)  # type: ignore[misc]
+    cls.__module__ = module_name
+
+    return cls

typemap/typing.py

@@ -292,6 +292,10 @@ class NewProtocol[*T]:
     pass
 
 
+class NewTypedDict[*T]:
+    pass
+
+
 class UpdateClass[*Ms]:
     pass