add default coerce to any Select2Field

flask_admin/_types.py

@@ -264,6 +264,10 @@ class T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK(T_FIELD_ARGS_VALIDATORS):
     allow_blank: NotRequired[bool]
 
 
+class T_FIELD_ARGS_VALIDATORS_SELECTABLE(T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK):
+    coerce: NotRequired[t.Callable[[t.Any], t.Any]]
+
+
 class T_FIELD_ARGS_VALIDATORS_FILES(T_FIELD_ARGS_VALIDATORS):
     base_path: NotRequired[str]
     allow_overwrite: NotRequired[bool]

flask_admin/contrib/peewee/view.py

@@ -26,6 +26,7 @@
 from flask_admin.model.form import InlineFormAdmin
 
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_FILTER
 from ..._types import T_PEEWEE_MODEL
 from ..._types import T_WIDGET
@@ -338,7 +339,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from

flask_admin/contrib/sqla/form.py

@@ -9,6 +9,8 @@
 from sqlalchemy import Boolean
 from sqlalchemy import Column
 from sqlalchemy.orm import ColumnProperty
+from sqlalchemy.sql.type_api import TypeEngine
+from sqlalchemy_utils import ChoiceType
 from wtforms import fields
 from wtforms import Form
 from wtforms import HiddenField
@@ -36,6 +38,7 @@
 from ..._types import T_FIELD_ARGS_VALIDATORS
 from ..._types import T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_INSTRUMENTED_ATTRIBUTE
 from ..._types import T_MODEL_VIEW
 from ..._types import T_ORM_MODEL
@@ -230,7 +233,7 @@ def convert(
         if isinstance(prop, FieldPlaceholder):
             return form.recreate_field(prop.field)
 
-        kwargs: T_FIELD_ARGS_VALIDATORS_ALLOW_BLANK = {"validators": [], "filters": []}
+        kwargs: T_FIELD_ARGS_VALIDATORS_SELECTABLE = {"validators": [], "filters": []}
 
         if field_args:
             kwargs.update(field_args)  # type: ignore[typeddict-item]
@@ -360,7 +363,11 @@ def convert(
             form_choices = getattr(self.view, "form_choices", None)
             if mapper.class_ == self.view.model and form_choices:
                 choices = form_choices.get(prop.key)
+
                 if choices:
+                    if "coerce" not in kwargs:
+                        kwargs["coerce"] = coerce_factory(column.type)
+
                     return form.Select2Field(  # type: ignore[misc]
                         choices=choices,
                         allow_blank=column.nullable,  # type: ignore[arg-type]
@@ -655,6 +662,18 @@ def avoid_empty_strings(value: T) -> T | None:
     return value if value else None
 
 
+def coerce_factory(type_: TypeEngine[t.Any]) -> t.Callable[[t.Any], t.Any]:
+    """
+    Return a function to coerce a column, for use by Select2Field.
+    :param type_: Column type
+    """
+
+    if isinstance(type_, ChoiceType):
+        return choice_type_coerce_factory(type_)
+    else:
+        return type_.python_type
+
+
 def choice_type_coerce_factory(type_: T_CHOICE_TYPE) -> t.Callable[[t.Any], t.Any]:
     """
     Return a function to coerce a ChoiceType column, for use by Select2Field.
@@ -671,8 +690,10 @@ def choice_type_coerce_factory(type_: T_CHOICE_TYPE) -> t.Callable[[t.Any], t.An
     def choice_coerce(value: t.Any) -> t.Any:
         if value is None:
             return None
+
         if isinstance(value, choice_cls):
             return getattr(value, key)
+
         return type_.python_type(value)
 
     return choice_coerce
@@ -699,7 +720,10 @@ def get_form(
     base_class: type[form.BaseForm] = form.BaseForm,
     only: t.Collection[str | T_INSTRUMENTED_ATTRIBUTE] | None = None,
     exclude: t.Collection[str | T_INSTRUMENTED_ATTRIBUTE] | None = None,
-    field_args: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+    field_args: dict[
+        str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+    ]
+    | None = None,
     hidden_pk: bool = False,
     ignore_hidden: bool = True,
     extra_fields: dict[str | T_INSTRUMENTED_ATTRIBUTE, UnboundField[t.Any]]

flask_admin/contrib/sqla/view.py

@@ -39,6 +39,7 @@
 from ..._types import T_COLUMN
 from ..._types import T_COLUMN_LIST
 from ..._types import T_FIELD_ARGS_VALIDATORS_FILES
+from ..._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from ..._types import T_FILTER
 from ..._types import T_INSTRUMENTED_ATTRIBUTE
 from ..._types import T_SQLALCHEMY_COLUMN
@@ -892,7 +893,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from

flask_admin/form/fields.py

@@ -4,6 +4,7 @@
 import time
 import typing as t
 from enum import Enum
+from inspect import isclass
 
 from wtforms import fields
 from wtforms.form import BaseForm
@@ -196,6 +197,9 @@ def process_formdata(self, valuelist: t.Sequence[str] | None) -> None:
                 self.data = None
             else:
                 try:
+                    if isclass(self.coerce) and issubclass(self.coerce, Enum):
+                        self.coerce = self._enum_coerce_factory(self.coerce)
+
                     self.data = self.coerce(valuelist[0])
                 except ValueError as err:
                     raise ValueError(
@@ -208,6 +212,28 @@ def pre_validate(self, form: BaseForm) -> None:
 
         super().pre_validate(form)
 
+    def _enum_coerce_factory(self, type_: type[Enum]) -> t.Callable[[t.Any], t.Any]:
+        """
+        Return a function to coerce an Enum column, for use by Select2Field.
+        :param type_: Enum class
+        """
+
+        def enum_coerce(value: t.Any) -> t.Any:
+            if value is None:
+                return None
+
+            if isinstance(value, type_):
+                return value
+
+            ename = getattr(value, "name", value)
+            ename = str(value).replace(type_.__name__ + ".", "")
+            try:
+                return type_[ename]
+            except KeyError:
+                return type_(value)
+
+        return enum_coerce
+
 
 class Select2TagsField(fields.StringField):
     """`Select2Tags <http://ivaynberg.github.com/select2/#tags>`_ styled text field.

flask_admin/model/base.py

@@ -28,6 +28,7 @@
 from .._types import T_COLUMN_LIST
 from .._types import T_COLUMN_TYPE_FORMATTERS
 from .._types import T_FIELD_ARGS_VALIDATORS_FILES
+from .._types import T_FIELD_ARGS_VALIDATORS_SELECTABLE
 from .._types import T_FILTER
 from .._types import T_INSTRUMENTED_ATTRIBUTE
 from .._types import T_ORM_MODEL
@@ -654,7 +655,10 @@ class MyModelView(BaseModelView):
 
     """
 
-    form_args: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None
+    form_args: (
+        dict[str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE]
+        | None
+    ) = None
     """
         Dictionary of form field arguments. Refer to WTForms documentation for
         list of possible options.
@@ -1389,7 +1393,10 @@ def scaffold_form(self) -> type[Form]:
     def scaffold_list_form(
         self,
         widget: type[T_WIDGET] | None = None,
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None,
+        validators: dict[
+            str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+        ]
+        | None = None,
     ) -> type[Form]:
         """
         Create form for the `index_view` using only the columns from
@@ -1442,7 +1449,12 @@ class MyModelView(BaseModelView):
                 def get_list_form(self):
                     return self.scaffold_list_form(widget=CustomWidget)
         """
-        validators: dict[str, T_FIELD_ARGS_VALIDATORS_FILES] | None = None
+        validators: (
+            dict[
+                str, T_FIELD_ARGS_VALIDATORS_FILES | T_FIELD_ARGS_VALIDATORS_SELECTABLE
+            ]
+            | None
+        ) = None
         if self.form_args:
             # get only validators, other form_args can break FieldList wrapper
             validators = dict(