Add support of 'Self'

Author: the-glu

src/implicitdict/__init__.py

@@ -4,7 +4,15 @@
 from dataclasses import dataclass
 from datetime import datetime as datetime_type
 from types import UnionType
-from typing import Literal, Optional, Union, get_args, get_origin, get_type_hints  # pyright:ignore[reportDeprecated]
+from typing import (  # pyright:ignore[reportDeprecated]
+    Literal,
+    Optional,
+    Self,
+    Union,
+    get_args,
+    get_origin,
+    get_type_hints,
+)
 
 import arrow
 import pytimeparse
@@ -101,7 +109,7 @@ def parse(cls, source: dict, parse_type: type):
             if key in hints:
                 # This entry has an explicit type
                 try:
-                    kwargs[key] = _parse_value(value, hints[key])
+                    kwargs[key] = _parse_value(value, hints[key], parse_type)
                 except _PARSING_ERRORS as e:
                     raise _bubble_up_parse_error(e, key)
             else:
@@ -175,7 +183,7 @@ def has_field_with_value(self, field_name: str) -> bool:
         return field_name in self and self[field_name] is not None
 
 
-def _parse_value(value, value_type: type):
+def _parse_value(value, value_type: type, root_type: type):
     generic_type = get_origin(value_type)
     if generic_type:
         # Type is generic
@@ -192,7 +200,7 @@ def _parse_value(value, value_type: type):
             result = []
             for i, v in enumerate(value_list):
                 try:
-                    result.append(_parse_value(v, arg_types[0]))
+                    result.append(_parse_value(v, arg_types[0], root_type))
                 except _PARSING_ERRORS as e:
                     raise _bubble_up_parse_error(e, f"[{i}]")
             return result
@@ -201,9 +209,9 @@ def _parse_value(value, value_type: type):
             # value is a dict of some kind
             result = {}
             for k, v in value.items():
-                parsed_key = k if arg_types[0] is str else _parse_value(k, arg_types[0])
+                parsed_key = k if arg_types[0] is str else _parse_value(k, arg_types[0], root_type)
                 try:
-                    parsed_value = _parse_value(v, arg_types[1])
+                    parsed_value = _parse_value(v, arg_types[1], root_type)
                 except _PARSING_ERRORS as e:
                     raise _bubble_up_parse_error(e, k)
                 result[parsed_key] = parsed_value
@@ -220,7 +228,7 @@ def _parse_value(value, value_type: type):
                 # omitting the field's value
                 return None
             else:
-                return _parse_value(value, arg_types[0])
+                return _parse_value(value, arg_types[0], root_type)
 
         elif generic_type is Literal and len(arg_types) == 1:
             # Type is a Literal (parsed value must match specified value)
@@ -231,12 +239,15 @@ def _parse_value(value, value_type: type):
         else:
             raise ValueError(f"Automatic parsing of {value_type} type is not yet implemented")
 
+    elif value_type == Self:
+        # value is outself type
+        return ImplicitDict.parse(value, root_type)
     elif issubclass(value_type, ImplicitDict):
         # value is an ImplicitDict
         return ImplicitDict.parse(value, value_type)
 
     if hasattr(value_type, "__orig_bases__") and value_type.__orig_bases__:
-        return value_type(_parse_value(value, value_type.__orig_bases__[0]))
+        return value_type(_parse_value(value, value_type.__orig_bases__[0], root_type))
 
     else:
         # value is a non-generic type that is not an ImplicitDict

src/implicitdict/jsonschema.py

@@ -6,7 +6,7 @@
 from dataclasses import dataclass
 from datetime import datetime
 from types import UnionType
-from typing import Literal, TypeAlias, Union, cast, get_args, get_origin, get_type_hints
+from typing import Literal, Self, TypeAlias, Union, cast, get_args, get_origin, get_type_hints
 
 from . import ImplicitDict, StringBasedDateTime, StringBasedTimeDelta, _fullname, _get_fields
 
@@ -170,6 +170,12 @@ def _schema_for(
 
     schema_vars = schema_vars_resolver(value_type)
 
+    if value_type == Self:
+        if not schema_vars.path_to:
+            raise NotImplementedError(f"SchemaVarsResolver for {value_type} didn't returned a path_to function")
+
+        return {"$ref": schema_vars.path_to(context, context)}, False
+
     if issubclass(value_type, ImplicitDict):
         make_json_schema(value_type, schema_vars_resolver, schema_repository)
 

tests/test_jsonschema.py

@@ -1,4 +1,5 @@
 import json
+from typing import Self
 
 import jsonschema
 
@@ -8,11 +9,13 @@
 
 from .test_types import (
     ContainerData,
+    HiddenReferencingSelf,
     InheritanceData,
     NestedDefinitionsData,
     NormalUsageData,
     OptionalData,
     PropertiesData,
+    ReferencingSelf,
     SpecialSubclassesContainer,
     SpecialTypesData,
 )
@@ -28,10 +31,26 @@ def path_to(t_dest: type, t_src: type) -> str:
 
 
 def _verify_schema_validation(obj, obj_type: type[ImplicitDict]) -> None:
+    def _root_resolver(t: type) -> SchemaVars:
+        """Special resolver that references '#' for Self at root of the schema"""
+
+        if t == Self:
+
+            def path_to(t_dest: type, t_src: type) -> str:
+                if t_src == obj_type:
+                    return "#"
+                else:
+                    return "#/definitions/" + t_dest.__module__ + t_dest.__qualname__
+
+            full_name = t.__module__ + t.__qualname__
+            return SchemaVars(name=full_name, path_to=path_to)
+
+        return _resolver(t)
+
     repo = {}
-    implicitdict.jsonschema.make_json_schema(obj_type, _resolver, repo)
+    implicitdict.jsonschema.make_json_schema(obj_type, _root_resolver, repo)
 
-    name = _resolver(obj_type).name
+    name = _root_resolver(obj_type).name
     schema = repo[name]
     del repo[name]
     if repo:
@@ -113,3 +132,13 @@ def test_special_types():
 def test_nested_definitions():
     data = NestedDefinitionsData.example_value()
     _verify_schema_validation(data, NestedDefinitionsData)
+
+
+def test_self():
+    data = ReferencingSelf.example_value()
+    _verify_schema_validation(data, ReferencingSelf)
+
+
+def test_hidden_self():
+    data = HiddenReferencingSelf.example_value()
+    _verify_schema_validation(data, HiddenReferencingSelf)

tests/test_types.py

@@ -2,7 +2,7 @@
 # comments)
 import enum
 from datetime import UTC, datetime
-from typing import List, Optional  # noqa UP035
+from typing import List, Optional, Self  # noqa UP035
 
 from implicitdict import ImplicitDict, StringBasedDateTime, StringBasedTimeDelta
 
@@ -210,3 +210,47 @@ def example_value():
             },
             NestedDefinitionsData,
         )
+
+
+class ReferencingSelf(ImplicitDict):
+    foo: str
+    bar: Self | None
+
+    @staticmethod
+    def example_value():
+        return ImplicitDict.parse(
+            {
+                "foo": "foo",
+                "bar": {
+                    "foo": "subfoo",
+                },
+            },
+            ReferencingSelf,
+        )
+
+
+class HiddenReferencingSelf(ImplicitDict):
+    baz: ReferencingSelf
+    bazs: list[ReferencingSelf]
+
+    @staticmethod
+    def example_value():
+        return ImplicitDict.parse(
+            {
+                "baz": {
+                    "foo": "foo",
+                    "bar": {
+                        "foo": "subfoo",
+                    },
+                },
+                "bazs": [
+                    {
+                        "foo": "foo",
+                        "bar": {
+                            "foo": "subfoo",
+                        },
+                    }
+                ],
+            },
+            HiddenReferencingSelf,
+        )