See Changelog.

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Highlights

• Hypothesis plugin for testing, #2097 by @Zac-HD
• support for NamedTuple and TypedDict, #2216 by @PrettyWood
• Support Annotated hints on model fields, #2147 by @JacobHayes
• frozen parameter on Config to allow models to be hashed, #1880 by @rhuille

Changes

• Breaking Change, remove old deprecation aliases from v1, #2415 by @samuelcolvin:
  • remove notes on migrating to v1 in docs
  • remove Schema which was replaced by Field
  • remove Config.case_insensitive which was replaced by Config.case_sensitive (default False)
  • remove Config.allow_population_by_alias which was replaced by Config.allow_population_by_field_name
  • remove model.fields which was replaced by model.__fields__
  • remove model.to_string() which was replaced by str(model)
  • remove model.__values__ which was replaced by model.__dict__
• Breaking Change: always validate only first sublevel items with each_item. There were indeed some edge cases with some compound types where the validated items were the last sublevel ones, #1933 by @PrettyWood
• Update docs extensions to fix local syntax highlighting, #2400 by @daviskirk
• fix: allow utils.lenient_issubclass to handle typing.GenericAlias objects like list[str] in python >= 3.9, #2399 by @daviskirk
• Improve field declaration for pydantic dataclass by allowing the usage of pydantic Field or 'metadata' kwarg of dataclasses.field, #2384 by @PrettyWood
• Making typing-extensions a required dependency, #2368 by @samuelcolvin
• Make resolve_annotations more lenient, allowing for missing modules, #2363 by @samuelcolvin
• Allow configuring models through class kwargs, #2356 by @MrMrRobat
• Prevent Mapping subclasses from always being coerced to dict, #2325 by @ofek
• fix: allow None for type Optional[conset / conlist], #2320 by @PrettyWood
• Support empty tuple type, #2318 by @PrettyWood
• fix: python_requires metadata to require >=3.6.1, #2306 by @hukkinj1
• Properly encode Decimal with, or without any decimal places, #2293 by @hultner
• fix: update __fields_set__ in BaseModel.copy(update=…), #2290 by @PrettyWood
• fix: keep order of fields with BaseModel.construct(), #2281 by @PrettyWood
• Support generating schema for Generic fields, #2262 by @maximberg
• Fix validate_decorator so **kwargs doesn't exclude values when the keyword has the same name as the *args or **kwargs names, #2251 by @cybojenix
• Prevent overriding positional arguments with keyword arguments in validate_arguments, as per behaviour with native functions, #2249 by @cybojenix
• add documentation for con* type functions, #2242 by @tayoogunbiyi
• Support custom root type (aka __root__) when using parse_obj() with nested models, #2238 by @PrettyWood
• Support custom root type (aka __root__) with from_orm(), #2237 by @PrettyWood
• ensure cythonized functions are left untouched when creating models, based on #1944 by @kollmats, #2228 by @samuelcolvin
• Resolve forward refs for stdlib dataclasses converted into pydantic ones, #2220 by @PrettyWood
• Add support for NamedTuple and TypedDict types. Those two types are now handled and validated when used inside BaseModel or pydantic dataclass. Two utils are also added create_model_from_namedtuple and create_model_from_typeddict, #2216 by @PrettyWood
• Do not ignore annotated fields when type is Union[Type[...], ...], #2213 by @PrettyWood
• Raise a user-friendly TypeError when a root_validator does not return a dict (e.g. None), #2209 by @masalim2
• Add a FrozenSet[str] type annotation to the allowed_schemes argument on the strict_url field type, #2198 by @Midnighter
• add allow_mutation constraint to Field, #2195 by @sblack-usu
• Allow Field with a default_factory to be used as an argument to a function decorated with validate_arguments, #2176 by @thomascobb
• Allow non-existent secrets directory by only issuing a warning, #2175 by @davidolrik
• fix URL regex to parse fragment without query string, #2168 by @andrewmwhite
• fix: ensure to always return one of the values in Literal field type, #2166 by @PrettyWood
• Support typing.Annotated hints on model fields. A Field may now be set in the type hint with Annotated[..., Field(...); all other annotations are ignored but still visible with get_type_hints(..., include_extras=True), #2147 by @JacobHayes
• Added StrictBytes type as well as strict=False option to ConstrainedBytes, #2136 by @rlizzo
• added Config.anystr_lower and to_lower kwarg to constr and conbytes, #2134 by @tayoogunbiyi
• Support plain typing.Tuple type, #2132 by @PrettyWood
• Add a bound method validate to functions decorated with validate_arguments to validate parameters without actually calling the function, #2127 by @PrettyWood
• Add the ability to customize settings sources (add / disable / change priority order), #2107 by @kozlek
• Fix mypy complaints about most custom pydantic types, #2098 by @PrettyWood
• Add a Hypothesis plugin for easier property-based testing with Pydantic's custom types - usage details here, #2097 by @Zac-HD
• add validator for None, NoneType or Literal[None], #2095 by @PrettyWood
• Handle properly fields of type Callable with a default value, #2094 by @PrettyWood
• Updated create_model return type annotation to return type which inherits from __base__ argument, #2071 by @uriyyo
• Add merged json_encoders inheritance, #2064 by @art049
• allow overwriting ClassVars in sub-models without having to re-annotate them, #2061 by @layday
• add default encoder for Pattern type, #2045 by @PrettyWood
• Add NonNegativeInt, NonPositiveInt, NonNegativeFloat, NonPositiveFloat, #1975 by @mdavis-xyz
• Use % for percentage in string format of colors, #1960 by @EdwardBetts
• Fixed issue causing KeyError to be raised when building schema from multiple BaseModel with the same names declared in separate classes, #1912 by @JSextonn
• Add rediss (Redis over SSL) protocol to RedisDsn Allow URLs without user part (e.g., rediss://:pass@localhost), #1911 by @TrDex
• Add a new frozen boolean parameter to Config (default: False). Setting frozen=True does everything that allow_mutation=False does, and also generates a __hash__() method for the model. This makes instances of the model potentially hashable if all the attributes are hashable, #1880 by @rhuille
• fix schema generation with multiple Enums having the same name, #1857 by @PrettyWood
• Added support for 13/19 digits VISA credit cards in PaymentCardNumber type, #1416 by @AlexanderSov
• fix: prevent RecursionError while using recursive GenericModels, #1370 by @xppt
• use enum for typing.Literal in JSON schema, #1350 by @PrettyWood
• Fix: some recursive models did not require update_forward_refs and silently behaved incorrectly, #1201 by @PrettyWood
• Fix bug where generic models with fields where the typevar is nested in another type a: List[T] are considered to be concrete. This allows these models to be subclassed and composed as expected, #947 by @daviskirk
• Add Config.copy_on_model_validation flag. When set to False, pydantic will keep models used as fields untouched on validation instead of reconstructing (copying) them, #265 by @PrettyWood