pydantic · samuelcolvin · Oct 26, 2022 · Oct 25, 2022 · Oct 25, 2022 · Oct 25, 2022
diff --git a/README.md b/README.md
@@ -64,7 +64,7 @@ except ValidationError as e:
     1 validation error for model
     age
       Input should be greater than or equal to 18
-      [kind=greater_than_equal, context={ge: 18}, input_value=11, input_type=int]
+      [type=greater_than_equal, context={ge: 18}, input_value=11, input_type=int]
     """
 ```
 

diff --git a/pydantic_core/__init__.py b/pydantic_core/__init__.py
@@ -1,6 +1,6 @@
 from ._pydantic_core import (
     PydanticCustomError,
-    PydanticKindError,
+    PydanticKnownError,
     PydanticOmit,
     SchemaError,
     SchemaValidator,
@@ -17,6 +17,6 @@
     'SchemaError',
     'ValidationError',
     'PydanticCustomError',
-    'PydanticKindError',
+    'PydanticKnownError',
     'PydanticOmit',
 )
diff --git a/pydantic_core/_pydantic_core.pyi b/pydantic_core/_pydantic_core.pyi
@@ -2,7 +2,7 @@ import decimal
 import sys
 from typing import Any, TypedDict
 
-from pydantic_core.core_schema import CoreConfig, CoreSchema, ErrorKind
+from pydantic_core.core_schema import CoreConfig, CoreSchema, ErrorType
 
 if sys.version_info < (3, 11):
     from typing_extensions import NotRequired
@@ -16,7 +16,7 @@ __all__ = (
     'SchemaError',
     'ValidationError',
     'PydanticCustomError',
-    'PydanticKindError',
+    'PydanticKnownError',
     'PydanticOmit',
     'list_all_errors',
 )
@@ -42,7 +42,7 @@ class SchemaError(Exception):
     pass
 
 class ErrorDetails(TypedDict):
-    kind: str
+    type: str
     loc: 'list[int | str]'
     message: str
     input_value: Any
@@ -55,33 +55,33 @@ class ValidationError(ValueError):
     def errors(self, include_context: bool = True) -> 'list[ErrorDetails]': ...
 
 class PydanticCustomError(ValueError):
-    kind: str
+    type: str
     message_template: str
     context: 'dict[str, Any] | None'
 
-    def __init__(self, kind: str, message_template: str, context: 'dict[str, Any] | None' = None) -> None: ...
+    def __init__(self, error_type: str, message_template: str, context: 'dict[str, Any] | None' = None) -> None: ...
     def message(self) -> str: ...
 
-class PydanticKindError(ValueError):
-    kind: ErrorKind
+class PydanticKnownError(ValueError):
+    type: ErrorType
     message_template: str
     context: 'dict[str, str | int | float] | None'
 
     def __init__(
-        self, kind: ErrorKind, context: 'dict[str, str | int | float | decimal.Decimal] | None' = None
+        self, error_type: ErrorType, context: 'dict[str, str | int | float | decimal.Decimal] | None' = None
     ) -> None: ...
     def message(self) -> str: ...
 
 class PydanticOmit(Exception):
     def __init__(self) -> None: ...
 
-class ErrorKindInfo(TypedDict):
-    kind: ErrorKind
+class ErrorTypeInfo(TypedDict):
+    type: ErrorType
     message_template: str
     example_message: str
     example_context: 'dict[str, str | int | float] | None'
 
-def list_all_errors() -> 'list[ErrorKindInfo]':
+def list_all_errors() -> 'list[ErrorTypeInfo]':
     """
     Get information about all built-in errors.
     """
diff --git a/pydantic_core/core_schema.py b/pydantic_core/core_schema.py
@@ -736,16 +736,10 @@ def nullable_schema(
     return dict_not_none(type='nullable', schema=schema, strict=strict, ref=ref, extra=extra)
 
 
-class CustomError(TypedDict, total=False):
-    kind: Required[str]
-    message: str
-    context: Dict[str, Union[str, int]]
-
-
 class UnionSchema(TypedDict, total=False):
     type: Required[Literal['union']]
     choices: Required[List[CoreSchema]]
-    custom_error_kind: str
+    custom_error_type: str
     custom_error_message: str
     custom_error_context: Dict[str, Union[str, int, float]]
     strict: bool
@@ -755,7 +749,7 @@ class UnionSchema(TypedDict, total=False):
 
 def union_schema(
     *choices: CoreSchema,
-    custom_error_kind: str | None = None,
+    custom_error_type: str | None = None,
     custom_error_message: str | None = None,
     custom_error_context: dict[str, str | int] | None = None,
     strict: bool | None = None,
@@ -765,7 +759,7 @@ def union_schema(
     return dict_not_none(
         type='union',
         choices=choices,
-        custom_error_kind=custom_error_kind,
+        custom_error_type=custom_error_type,
         custom_error_message=custom_error_message,
         custom_error_context=custom_error_context,
         strict=strict,
@@ -780,7 +774,7 @@ class TaggedUnionSchema(TypedDict, total=False):
     discriminator: Required[
         Union[str, List[Union[str, int]], List[List[Union[str, int]]], Callable[[Any], Optional[str]]]
     ]
-    custom_error_kind: str
+    custom_error_type: str
     custom_error_message: str
     custom_error_context: Dict[str, Union[str, int, float]]
     strict: bool
@@ -792,7 +786,7 @@ def tagged_union_schema(
     choices: Dict[str, CoreSchema],
     discriminator: str | list[str | int] | list[list[str | int]] | Callable[[Any], str | None],
     *,
-    custom_error_kind: str | None = None,
+    custom_error_type: str | None = None,
     custom_error_message: str | None = None,
     custom_error_context: dict[str, int | str | float] | None = None,
     strict: bool | None = None,
@@ -803,7 +797,7 @@ def tagged_union_schema(
         type='tagged-union',
         choices=choices,
         discriminator=discriminator,
-        custom_error_kind=custom_error_kind,
+        custom_error_type=custom_error_type,
         custom_error_message=custom_error_message,
         custom_error_context=custom_error_context,
         strict=strict,
@@ -989,7 +983,7 @@ def recursive_reference_schema(schema_ref: str) -> RecursiveReferenceSchema:
 class CustomErrorSchema(TypedDict, total=False):
     type: Required[Literal['custom_error']]
     schema: Required[CoreSchema]
-    custom_error_kind: Required[str]
+    custom_error_type: Required[str]
     custom_error_message: str
     custom_error_context: Dict[str, Union[str, int, float]]
     ref: str
@@ -998,7 +992,7 @@ class CustomErrorSchema(TypedDict, total=False):
 
 def custom_error_schema(
     schema: CoreSchema,
-    custom_error_kind: str,
+    custom_error_type: str,
     *,
     custom_error_message: str | None = None,
     custom_error_context: dict[str, str | int | float] | None = None,
@@ -1008,7 +1002,7 @@ def custom_error_schema(
     return dict_not_none(
         type='custom_error',
         schema=schema,
-        custom_error_kind=custom_error_kind,
+        custom_error_type=custom_error_type,
         custom_error_message=custom_error_message,
         custom_error_context=custom_error_context,
         ref=ref,
@@ -1067,9 +1061,9 @@ def json_schema(schema: CoreSchema | None = None, *, ref: str | None = None, ext
     JsonSchema,
 ]
 
-# used in _pydantic_core.pyi::PydanticKindError
+# used in _pydantic_core.pyi::PydanticKnownError
 # to update this, call `pytest -k test_all_errors` and copy the output
-ErrorKind = Literal[
+ErrorType = Literal[
     'json_invalid',
     'json_type',
     'recursion_loop',

diff --git a/src/errors/line_error.rs b/src/errors/line_error.rs
@@ -4,8 +4,8 @@ use pyo3::PyDowncastError;
 
 use crate::input::{Input, JsonInput};
 
-use super::kinds::ErrorKind;
 use super::location::{LocItem, Location};
+use super::types::ErrorType;
 use super::validation_exception::{pretty_py_line_errors, PyLineError};
 
 pub type ValResult<'a, T> = Result<T, ValError<'a>>;
@@ -36,16 +36,16 @@ impl<'a> From<Vec<ValLineError<'a>>> for ValError<'a> {
 }
 
 impl<'a> ValError<'a> {
-    pub fn new(kind: ErrorKind, input: &'a impl Input<'a>) -> ValError<'a> {
-        Self::LineErrors(vec![ValLineError::new(kind, input)])
+    pub fn new(error_type: ErrorType, input: &'a impl Input<'a>) -> ValError<'a> {
+        Self::LineErrors(vec![ValLineError::new(error_type, input)])
     }
 
-    pub fn new_with_loc(kind: ErrorKind, input: &'a impl Input<'a>, loc: impl Into<LocItem>) -> ValError<'a> {
-        Self::LineErrors(vec![ValLineError::new_with_loc(kind, input, loc)])
+    pub fn new_with_loc(error_type: ErrorType, input: &'a impl Input<'a>, loc: impl Into<LocItem>) -> ValError<'a> {
+        Self::LineErrors(vec![ValLineError::new_with_loc(error_type, input, loc)])
     }
 
-    pub fn new_custom_input(kind: ErrorKind, input_value: InputValue<'a>) -> ValError<'a> {
-        Self::LineErrors(vec![ValLineError::new_custom_input(kind, input_value)])
+    pub fn new_custom_input(error_type: ErrorType, input_value: InputValue<'a>) -> ValError<'a> {
+        Self::LineErrors(vec![ValLineError::new_custom_input(error_type, input_value)])
     }
 
     /// helper function to call with_outer on line items if applicable
@@ -81,32 +81,32 @@ pub fn pretty_line_errors(py: Python, line_errors: Vec<ValLineError>) -> String
 /// I don't like the name `ValLineError`, but it's the best I could come up with (for now).
 #[cfg_attr(debug_assertions, derive(Debug))]
 pub struct ValLineError<'a> {
-    pub kind: ErrorKind,
+    pub error_type: ErrorType,
     // location is reversed so that adding an "outer" location item is pushing, it's reversed before showing to the user
     pub location: Location,
     pub input_value: InputValue<'a>,
 }
 
 impl<'a> ValLineError<'a> {
-    pub fn new(kind: ErrorKind, input: &'a impl Input<'a>) -> ValLineError<'a> {
+    pub fn new(error_type: ErrorType, input: &'a impl Input<'a>) -> ValLineError<'a> {
         Self {
-            kind,
+            error_type,
             input_value: input.as_error_value(),
             location: Location::default(),
         }
     }
 
-    pub fn new_with_loc(kind: ErrorKind, input: &'a impl Input<'a>, loc: impl Into<LocItem>) -> ValLineError<'a> {
+    pub fn new_with_loc(error_type: ErrorType, input: &'a impl Input<'a>, loc: impl Into<LocItem>) -> ValLineError<'a> {
         Self {
-            kind,
+            error_type,
             input_value: input.as_error_value(),
             location: Location::new_some(loc.into()),
         }
     }
 
-    pub fn new_custom_input(kind: ErrorKind, input_value: InputValue<'a>) -> ValLineError<'a> {
+    pub fn new_custom_input(error_type: ErrorType, input_value: InputValue<'a>) -> ValLineError<'a> {
         Self {
-            kind,
+            error_type,
             input_value,
             location: Location::default(),
         }
@@ -119,16 +119,16 @@ impl<'a> ValLineError<'a> {
         self
     }
 
-    // change the kind on a error in place
-    pub fn with_kind(mut self, kind: ErrorKind) -> Self {
-        self.kind = kind;
+    // change the error_type on a error in place
+    pub fn with_type(mut self, error_type: ErrorType) -> Self {
+        self.error_type = error_type;
         self
     }
 
     /// a bit like clone but change the lifetime to match py, used by ValError.duplicate above
     pub fn duplicate<'py>(&'a self, py: Python<'py>) -> ValLineError<'py> {
         ValLineError {
-            kind: self.kind.clone(),
+            error_type: self.error_type.clone(),
             input_value: InputValue::<'py>::from(self.input_value.to_object(py)),
             location: self.location.clone(),
         }

diff --git a/src/errors/location.rs b/src/errors/location.rs
@@ -1,7 +1,8 @@
+use pyo3::once_cell::GILOnceCell;
 use std::fmt;
 
 use pyo3::prelude::*;
-use pyo3::types::PyList;
+use pyo3::types::PyTuple;
 
 /// Used to store individual items of the error location, e.g. a string for key/field names
 /// or a number for array indices.
@@ -85,11 +86,15 @@ impl Default for Location {
     }
 }
 
+static EMPTY_TUPLE: GILOnceCell<PyObject> = GILOnceCell::new();
+
 impl ToPyObject for Location {
     fn to_object(&self, py: Python<'_>) -> PyObject {
         match self {
-            Self::List(loc) => loc.iter().rev().collect::<Vec<_>>().to_object(py),
-            Self::Empty => PyList::empty(py).to_object(py),
+            Self::List(loc) => PyTuple::new(py, loc.iter().rev()).to_object(py),
+            Self::Empty => EMPTY_TUPLE
+                .get_or_init(py, || PyTuple::empty(py).to_object(py))
+                .clone_ref(py),
         }
     }
 }

diff --git a/src/errors/mod.rs b/src/errors/mod.rs
@@ -1,16 +1,16 @@
 use pyo3::prelude::*;
 
-mod kinds;
 mod line_error;
 mod location;
+mod types;
 mod validation_exception;
 mod value_exception;
 
-pub use self::kinds::{list_all_errors, ErrorKind};
 pub use self::line_error::{pretty_line_errors, InputValue, ValError, ValLineError, ValResult};
 pub use self::location::LocItem;
+pub use self::types::{list_all_errors, ErrorType};
 pub use self::validation_exception::ValidationError;
-pub use self::value_exception::{PydanticCustomError, PydanticKindError, PydanticOmit};
+pub use self::value_exception::{PydanticCustomError, PydanticKnownError, PydanticOmit};
 
 pub fn py_err_string(py: Python, err: PyErr) -> String {
     let value = err.value(py);