add decimal validator

generate_self_schema.py

@@ -6,6 +6,7 @@
 """
 from __future__ import annotations as _annotations
 
+import decimal
 import importlib.util
 import re
 from collections.abc import Callable
@@ -23,6 +24,7 @@
     UnionType = Union[TypingUnionType, TypesUnionType]
 
 except ImportError:
+    TypesUnionType = None
     UnionType = TypingUnionType
 
 
@@ -46,8 +48,8 @@
 def get_schema(obj) -> core_schema.CoreSchema:
     if isinstance(obj, str):
         return {'type': obj}
-    elif obj in (datetime, timedelta, date, time, bool, int, float, str):
-        return {'type': obj.__name__}
+    elif obj in (datetime, timedelta, date, time, bool, int, float, str, decimal.Decimal):
+        return {'type': obj.__name__.lower()}
     elif is_typeddict(obj):
         return type_dict_schema(obj)
     elif obj == Any or obj == type:
@@ -57,7 +59,7 @@ def get_schema(obj) -> core_schema.CoreSchema:
 
     origin = get_origin(obj)
     assert origin is not None, f'origin cannot be None, obj={obj}, you probably need to fix generate_self_schema.py'
-    if origin is Union:
+    if origin is Union or origin is TypesUnionType:
         return union_schema(obj)
     elif obj is Callable or origin is Callable:
         return {'type': 'callable'}
@@ -79,6 +81,7 @@ def get_schema(obj) -> core_schema.CoreSchema:
         # can't really use 'is-instance' since this is used for the class_ parameter of 'is-instance' validators
         return {'type': 'any'}
     else:
+        print(origin)
         # debug(obj)
         raise TypeError(f'Unknown type: {obj!r}')
 

python/pydantic_core/core_schema.py

@@ -8,6 +8,7 @@
 import sys
 from collections.abc import Mapping
 from datetime import date, datetime, time, timedelta
+from decimal import Decimal
 from typing import TYPE_CHECKING, Any, Callable, Dict, Hashable, List, Optional, Set, Type, Union
 
 if sys.version_info < (3, 11):
@@ -658,6 +659,72 @@ def float_schema(
     )
 
 
+class DecimalSchema(TypedDict, total=False):
+    type: Required[Literal['decimal']]
+    gt: int | Decimal
+    ge: int | Decimal
+    lt: int | Decimal
+    le: int | Decimal
+    max_digits: int
+    decimal_places: int
+    multiple_of: int | Decimal
+    allow_inf_nan: bool  # whether 'NaN', '+inf', '-inf' should be forbidden. default: False
+    check_digits: bool  # FIXME document. default: False
+    strict: bool
+    ref: str
+    metadata: Any
+    serialization: SerSchema
+
+
+def decimal_schema(
+    *,
+    gt: int | Decimal | None = None,
+    ge: int | Decimal | None = None,
+    lt: int | Decimal | None = None,
+    le: int | Decimal | None = None,
+    max_digits: int | None = None,
+    decimal_places: int | None = None,
+    multiple_of: int | Decimal | None = None,
+    allow_inf_nan: bool = None,
+    check_digits: bool = None,
+    strict: bool | None = None,
+    ref: str | None = None,
+    metadata: Any = None,
+    serialization: SerSchema | None = None,
+) -> DecimalSchema:
+    """
+    Returns a schema that matches a decimal value, e.g.:
+
+    ```py
+    from decimal import Decimal
+    from pydantic_core import SchemaValidator, core_schema
+
+    schema = core_schema.decimal_schema(le=0.8, ge=0.2)
+    v = SchemaValidator(schema)
+    assert v.validate_python('0.5') == Decimal('0.5')
+    ```
+
+    Args:
+        FIXME document
+    """
+    return _dict_not_none(
+        type='decimal',
+        gt=gt,
+        ge=ge,
+        lt=lt,
+        le=le,
+        max_digits=max_digits,
+        decimal_places=decimal_places,
+        multiple_of=multiple_of,
+        allow_inf_nan=allow_inf_nan,
+        check_digits=check_digits,
+        strict=strict,
+        ref=ref,
+        metadata=metadata,
+        serialization=serialization,
+    )
+
+
 class StringSchema(TypedDict, total=False):
     type: Required[Literal['str']]
     pattern: str
@@ -3690,6 +3757,7 @@ def definition_reference_schema(
         BoolSchema,
         IntSchema,
         FloatSchema,
+        DecimalSchema,
         StringSchema,
         BytesSchema,
         DateSchema,
@@ -3743,6 +3811,7 @@ def definition_reference_schema(
     'bool',
     'int',
     'float',
+    'decimal',
     'str',
     'bytes',
     'date',

src/errors/mod.rs

@@ -8,7 +8,7 @@ mod value_exception;
 
 pub use self::line_error::{InputValue, ValError, ValLineError, ValResult};
 pub use self::location::LocItem;
-pub use self::types::{list_all_errors, ErrorMode, ErrorType};
+pub use self::types::{list_all_errors, ErrorMode, ErrorType, Number};
 pub use self::validation_exception::ValidationError;
 pub use self::value_exception::{PydanticCustomError, PydanticKnownError, PydanticOmit, PydanticUseDefault};
 

src/input/input_abstract.rs

@@ -152,6 +152,19 @@ pub trait Input<'a>: fmt::Debug + ToPyObject {
         self.strict_float()
     }
 
+    fn validate_decimal(&'a self, strict: bool, decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        if strict {
+            self.strict_decimal(decimal_type)
+        } else {
+            self.lax_decimal(decimal_type)
+        }
+    }
+    fn strict_decimal(&'a self, decimal_type: &'a PyType) -> ValResult<&'a PyAny>;
+    #[cfg_attr(has_no_coverage, no_coverage)]
+    fn lax_decimal(&'a self, decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        self.strict_decimal(decimal_type)
+    }
+
     fn validate_dict(&'a self, strict: bool) -> ValResult<GenericMapping<'a>> {
         if strict {
             self.strict_dict()

src/input/input_json.rs

@@ -1,11 +1,12 @@
 use std::borrow::Cow;
 
 use pyo3::prelude::*;
-use pyo3::types::PyDict;
+use pyo3::types::{PyDict, PyType};
 use speedate::MicrosecondsPrecisionOverflowBehavior;
 use strum::EnumMessage;
 
 use crate::errors::{ErrorType, InputValue, LocItem, ValError, ValResult};
+use crate::PydanticCustomError;
 
 use super::datetime::{
     bytes_as_date, bytes_as_datetime, bytes_as_time, bytes_as_timedelta, float_as_datetime, float_as_duration,
@@ -172,6 +173,25 @@ impl<'a> Input<'a> for JsonInput {
         }
     }
 
+    fn strict_decimal(&'a self, decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        match self {
+            JsonInput::String(str) => Ok(decimal_type.call1((str,))?),
+            _ =>
+            // FIXME make a known error
+            {
+                Err(ValError::new(
+                    ErrorType::new_custom_error(PydanticCustomError::py_new(
+                        decimal_type.py(),
+                        "decimal_type".into(),
+                        "Input should be a valid Decimal instance or decimal string in JSON".into(),
+                        None,
+                    )),
+                    self,
+                ))
+            }
+        }
+    }
+
     fn validate_dict(&'a self, _strict: bool) -> ValResult<GenericMapping<'a>> {
         match self {
             JsonInput::Object(dict) => Ok(dict.into()),
@@ -417,6 +437,10 @@ impl<'a> Input<'a> for String {
         }
     }
 
+    fn strict_decimal(&'a self, _decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        todo!()
+    }
+
     #[cfg_attr(has_no_coverage, no_coverage)]
     fn validate_dict(&'a self, _strict: bool) -> ValResult<GenericMapping<'a>> {
         Err(ValError::new(ErrorType::DictType, self))

src/input/input_python.rs

@@ -13,7 +13,7 @@ use speedate::MicrosecondsPrecisionOverflowBehavior;
 
 use crate::errors::{ErrorType, InputValue, LocItem, ValError, ValResult};
 use crate::tools::{extract_i64, safe_repr};
-use crate::{ArgsKwargs, PyMultiHostUrl, PyUrl};
+use crate::{ArgsKwargs, PyMultiHostUrl, PyUrl, PydanticCustomError};
 
 use super::datetime::{
     bytes_as_date, bytes_as_datetime, bytes_as_time, bytes_as_timedelta, date_as_datetime, float_as_datetime,
@@ -352,6 +352,64 @@ impl<'a> Input<'a> for PyAny {
         }
     }
 
+    fn strict_decimal(&'a self, decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        let py = self.py();
+
+        // Fast path for existing decimal objects
+        if self.is_exact_instance(decimal_type) {
+            return Ok(self);
+        }
+
+        // Try subclasses of decimals, they will be upcast to Decimal
+        if self.is_instance(decimal_type)? {
+            match decimal_type.call1((self,)) {
+                Ok(decimal) => return Ok(decimal),
+                Err(e) if e.is_instance(py, py.import("decimal")?.getattr("DecimalException")?) => {}
+                Err(e) => return Err(ValError::InternalErr(e)),
+            }
+        }
+
+        // FIXME make a known error
+        Err(ValError::new(
+            ErrorType::new_custom_error(PydanticCustomError::py_new(
+                self.py(),
+                "decimal_type".into(),
+                "Input should be a valid Decimal instance or decimal string in JSON".into(),
+                None,
+            )),
+            self,
+        ))
+    }
+
+    fn lax_decimal(&'a self, decimal_type: &'a PyType) -> ValResult<&'a PyAny> {
+        let py = self.py();
+
+        // Fast path for existing decimal objects
+        if self.is_exact_instance(decimal_type) {
+            return Ok(self);
+        }
+
+        // The decimal constructor will accept list and tuple types, but we don't want
+        // to accept them.
+        if !(self.is_instance_of::<PyTuple>() || self.is_instance_of::<PyList>()) {
+            match decimal_type.call1((self,)) {
+                Ok(decimal) => return Ok(decimal),
+                Err(e) if e.is_instance(py, py.import("decimal")?.getattr("DecimalException")?) => {}
+                Err(e) => return Err(ValError::InternalErr(e)),
+            }
+        };
+
+        Err(ValError::new(
+            ErrorType::new_custom_error(PydanticCustomError::py_new(
+                py,
+                "decimal_parsing".into(),
+                "input should be a valid decimal".into(),
+                None,
+            )),
+            self,
+        ))
+    }
+
     fn strict_dict(&'a self) -> ValResult<GenericMapping<'a>> {
         if let Ok(dict) = self.downcast::<PyDict>() {
             Ok(dict.into())

src/serializers/shared.rs

@@ -114,6 +114,7 @@ combined_serializer! {
         Int: super::type_serializers::simple::IntSerializer;
         Bool: super::type_serializers::simple::BoolSerializer;
         Float: super::type_serializers::simple::FloatSerializer;
+        Decimal: super::type_serializers::decimal::DecimalSerializer;
         Str: super::type_serializers::string::StrSerializer;
         Bytes: super::type_serializers::bytes::BytesSerializer;
         Datetime: super::type_serializers::datetime_etc::DatetimeSerializer;
@@ -228,6 +229,7 @@ impl PyGcTraverse for CombinedSerializer {
             CombinedSerializer::Int(inner) => inner.py_gc_traverse(visit),
             CombinedSerializer::Bool(inner) => inner.py_gc_traverse(visit),
             CombinedSerializer::Float(inner) => inner.py_gc_traverse(visit),
+            CombinedSerializer::Decimal(inner) => inner.py_gc_traverse(visit),
             CombinedSerializer::Str(inner) => inner.py_gc_traverse(visit),
             CombinedSerializer::Bytes(inner) => inner.py_gc_traverse(visit),
             CombinedSerializer::Datetime(inner) => inner.py_gc_traverse(visit),