Rewrite enum and text casting (#973)

* Rewrite enum and text casting

* Add doc tests

* Refactoring

src/entity/column.rs

@@ -1,5 +1,5 @@
-use crate::{EntityName, IdenStatic, Iterable};
-use sea_query::{Alias, BinOper, DynIden, Expr, SeaRc, SelectStatement, SimpleExpr, Value};
+use crate::{cast_text_as_enum, EntityName, IdenStatic, IntoSimpleExpr, Iterable};
+use sea_query::{BinOper, DynIden, Expr, SeaRc, SelectStatement, SimpleExpr, Value};
 use std::str::FromStr;
 
 /// Defines a Column for an Entity
@@ -100,13 +100,7 @@ macro_rules! bind_oper_with_enum_casting {
         where
             V: Into<Value>,
         {
-            let val = Expr::val(v);
-            let col_def = self.def();
-            let col_type = col_def.get_column_type();
-            let expr = match col_type.get_enum_name() {
-                Some(enum_name) => val.as_enum(Alias::new(enum_name)),
-                None => val.into(),
-            };
+            let expr = cast_text_as_enum(Expr::val(v), self);
             Expr::tbl(self.entity_name(), *self).binary(BinOper::$bin_op, expr)
         }
     };
@@ -305,6 +299,11 @@ pub trait ColumnTrait: IdenStatic + Iterable + FromStr {
 
     bind_subquery_func!(in_subquery);
     bind_subquery_func!(not_in_subquery);
+
+    /// Construct a [`SimpleExpr::Column`] wrapped in [`Expr`].
+    fn into_expr(self) -> Expr {
+        Expr::expr(self.into_simple_expr())
+    }
 }
 
 impl ColumnType {

src/executor/insert.rs

@@ -1,10 +1,8 @@
 use crate::{
-    error::*, ActiveModelTrait, ColumnTrait, ConnectionTrait, EntityTrait, Insert, IntoActiveModel,
-    Iterable, PrimaryKeyTrait, SelectModel, SelectorRaw, Statement, TryFromU64,
-};
-use sea_query::{
-    Alias, Expr, FromValueTuple, Iden, InsertStatement, IntoColumnRef, Query, ValueTuple,
+    cast_enum_as_text, error::*, ActiveModelTrait, ConnectionTrait, EntityTrait, Insert,
+    IntoActiveModel, Iterable, PrimaryKeyTrait, SelectModel, SelectorRaw, Statement, TryFromU64,
 };
+use sea_query::{Expr, FromValueTuple, Iden, InsertStatement, IntoColumnRef, Query, ValueTuple};
 use std::{future::Future, marker::PhantomData};
 
 /// Defines a structure to perform INSERT operations in an ActiveModel
@@ -149,16 +147,10 @@ where
     let db_backend = db.get_database_backend();
     let found = match db.support_returning() {
         true => {
-            let returning =
-                Query::returning().exprs(<A::Entity as EntityTrait>::Column::iter().map(|c| {
-                    let col = Expr::col(c);
-                    let col_def = ColumnTrait::def(&c);
-                    let col_type = col_def.get_column_type();
-                    match col_type.get_enum_name() {
-                        Some(_) => col.as_enum(Alias::new("text")),
-                        None => col.into(),
-                    }
-                }));
+            let returning = Query::returning().exprs(
+                <A::Entity as EntityTrait>::Column::iter()
+                    .map(|c| cast_enum_as_text(Expr::col(c), &c)),
+            );
             insert_statement.returning(returning);
             SelectorRaw::<SelectModel<<A::Entity as EntityTrait>::Model>>::from_statement(
                 db_backend.build(&insert_statement),

src/executor/update.rs

@@ -1,8 +1,8 @@
 use crate::{
-    error::*, ActiveModelTrait, ColumnTrait, ConnectionTrait, EntityTrait, IntoActiveModel,
+    cast_enum_as_text, error::*, ActiveModelTrait, ConnectionTrait, EntityTrait, IntoActiveModel,
     Iterable, SelectModel, SelectorRaw, Statement, UpdateMany, UpdateOne,
 };
-use sea_query::{Alias, Expr, FromValueTuple, Query, UpdateStatement};
+use sea_query::{Expr, FromValueTuple, Query, UpdateStatement};
 use std::future::Future;
 
 /// Defines an update operation
@@ -91,16 +91,10 @@ where
 {
     match db.support_returning() {
         true => {
-            let returning =
-                Query::returning().exprs(<A::Entity as EntityTrait>::Column::iter().map(|c| {
-                    let col = Expr::col(c);
-                    let col_def = c.def();
-                    let col_type = col_def.get_column_type();
-                    match col_type.get_enum_name() {
-                        Some(_) => col.as_enum(Alias::new("text")),
-                        None => col.into(),
-                    }
-                }));
+            let returning = Query::returning().exprs(
+                <A::Entity as EntityTrait>::Column::iter()
+                    .map(|c| cast_enum_as_text(Expr::col(c), &c)),
+            );
             query.returning(returning);
             let db_backend = db.get_database_backend();
             let found: Option<<A::Entity as EntityTrait>::Model> =

src/query/combine.rs

@@ -1,12 +1,10 @@
 use crate::{
-    ColumnTrait, EntityTrait, IdenStatic, IntoSimpleExpr, Iterable, QueryTrait, Select, SelectTwo,
-    SelectTwoMany,
+    cast_enum_as_text, ColumnTrait, EntityTrait, IdenStatic, Iterable, QueryTrait, Select,
+    SelectTwo, SelectTwoMany,
 };
 use core::marker::PhantomData;
 pub use sea_query::JoinType;
-use sea_query::{
-    Alias, ColumnRef, DynIden, Expr, Iden, Order, SeaRc, SelectExpr, SelectStatement, SimpleExpr,
-};
+use sea_query::{Alias, ColumnRef, Iden, Order, SeaRc, SelectExpr, SelectStatement, SimpleExpr};
 
 macro_rules! select_def {
     ( $ident: ident, $str: expr ) => {
@@ -148,18 +146,10 @@ where
     F: EntityTrait,
     S: QueryTrait<QueryStatement = SelectStatement>,
 {
-    let text_type = SeaRc::new(Alias::new("text")) as DynIden;
     for col in <F::Column as Iterable>::iter() {
-        let col_def = col.def();
-        let col_type = col_def.get_column_type();
         let alias = format!("{}{}", SelectB.as_str(), col.as_str());
-        let expr = Expr::expr(col.into_simple_expr());
-        let expr = match col_type.get_enum_name() {
-            Some(_) => expr.as_enum(text_type.clone()),
-            None => expr.into(),
-        };
         selector.query().expr(SelectExpr {
-            expr,
+            expr: cast_enum_as_text(col.into_expr(), &col),
             alias: Some(SeaRc::new(Alias::new(&alias))),
             window: None,
         });

src/query/helper.rs

@@ -38,11 +38,34 @@ pub trait QuerySelect: Sized {
     ///     r#"SELECT "cake"."name" FROM "cake""#
     /// );
     /// ```
+    ///
+    /// Enum column will be casted into text (PostgreSQL only)
+    ///
+    /// ```
+    /// use sea_orm::{entity::*, query::*, tests_cfg::lunch_set, DbBackend};
+    ///
+    /// assert_eq!(
+    ///     lunch_set::Entity::find()
+    ///         .select_only()
+    ///         .column(lunch_set::Column::Tea)
+    ///         .build(DbBackend::Postgres)
+    ///         .to_string(),
+    ///     r#"SELECT CAST("lunch_set"."tea" AS text) FROM "lunch_set""#
+    /// );
+    /// assert_eq!(
+    ///     lunch_set::Entity::find()
+    ///         .select_only()
+    ///         .column(lunch_set::Column::Tea)
+    ///         .build(DbBackend::MySql)
+    ///         .to_string(),
+    ///     r#"SELECT `lunch_set`.`tea` FROM `lunch_set`"#
+    /// );
+    /// ```
     fn column<C>(mut self, col: C) -> Self
     where
         C: ColumnTrait,
     {
-        self.query().expr(col.into_simple_expr());
+        self.query().expr(cast_enum_as_text(col.into_expr(), &col));
         self
     }
 
@@ -532,3 +555,33 @@ pub(crate) fn unpack_table_alias(table_ref: &TableRef) -> Option<DynIden> {
         | TableRef::DatabaseSchemaTableAlias(_, _, _, alias) => Some(SeaRc::clone(alias)),
     }
 }
+
+#[derive(Iden)]
+struct Text;
+
+pub(crate) fn cast_enum_as_text<C>(expr: Expr, col: &C) -> SimpleExpr
+where
+    C: ColumnTrait,
+{
+    cast_enum_text_inner(expr, col, |col, _| col.as_enum(Text))
+}
+
+pub(crate) fn cast_text_as_enum<C>(expr: Expr, col: &C) -> SimpleExpr
+where
+    C: ColumnTrait,
+{
+    cast_enum_text_inner(expr, col, |col, enum_name| col.as_enum(enum_name))
+}
+
+fn cast_enum_text_inner<C, F>(expr: Expr, col: &C, f: F) -> SimpleExpr
+where
+    C: ColumnTrait,
+    F: Fn(Expr, DynIden) -> SimpleExpr,
+{
+    let col_def = col.def();
+    let col_type = col_def.get_column_type();
+    match col_type.get_enum_name() {
+        Some(enum_name) => f(expr, SeaRc::new(Alias::new(enum_name))),
+        None => expr.into(),
+    }
+}

src/query/insert.rs

@@ -1,9 +1,9 @@
 use crate::{
-    ActiveModelTrait, ColumnTrait, EntityName, EntityTrait, IntoActiveModel, Iterable,
+    cast_text_as_enum, ActiveModelTrait, EntityName, EntityTrait, IntoActiveModel, Iterable,
     PrimaryKeyTrait, QueryTrait,
 };
 use core::marker::PhantomData;
-use sea_query::{Alias, Expr, InsertStatement, OnConflict, ValueTuple};
+use sea_query::{Expr, InsertStatement, OnConflict, ValueTuple};
 
 /// Performs INSERT operations on a ActiveModel
 #[derive(Debug)]
@@ -134,14 +134,7 @@ where
             }
             if av_has_val {
                 columns.push(col);
-                let val = Expr::val(av.into_value().unwrap());
-                let col_def = col.def();
-                let col_type = col_def.get_column_type();
-                let expr = match col_type.get_enum_name() {
-                    Some(enum_name) => val.as_enum(Alias::new(enum_name)),
-                    None => val.into(),
-                };
-                values.push(expr);
+                values.push(cast_text_as_enum(Expr::val(av.into_value().unwrap()), &col));
             }
         }
         self.query.columns(columns);

src/query/join.rs

@@ -1,9 +1,9 @@
 use crate::{
-    join_tbl_on_condition, unpack_table_ref, ColumnTrait, EntityTrait, IdenStatic, Iterable,
+    cast_enum_as_text, join_tbl_on_condition, unpack_table_ref, EntityTrait, IdenStatic, Iterable,
     Linked, QuerySelect, Related, Select, SelectA, SelectB, SelectTwo, SelectTwoMany,
 };
 pub use sea_query::JoinType;
-use sea_query::{Alias, Condition, DynIden, Expr, IntoIden, SeaRc, SelectExpr};
+use sea_query::{Alias, Condition, Expr, IntoIden, SeaRc, SelectExpr};
 
 impl<E> Select<E>
 where
@@ -92,22 +92,15 @@ where
                 .join_as(JoinType::LeftJoin, table_ref, to_tbl, condition);
         }
         slf = slf.apply_alias(SelectA.as_str());
-        let text_type = SeaRc::new(Alias::new("text")) as DynIden;
         let mut select_two = SelectTwo::new_without_prepare(slf.query);
         for col in <T::Column as Iterable>::iter() {
-            let col_def = col.def();
-            let col_type = col_def.get_column_type();
             let alias = format!("{}{}", SelectB.as_str(), col.as_str());
             let expr = Expr::tbl(
                 Alias::new(&format!("r{}", l.link().len() - 1)).into_iden(),
                 col.into_iden(),
             );
-            let expr = match col_type.get_enum_name() {
-                Some(_) => expr.as_enum(text_type.clone()),
-                None => expr.into(),
-            };
             select_two.query().expr(SelectExpr {
-                expr,
+                expr: cast_enum_as_text(expr, &col),
                 alias: Some(SeaRc::new(Alias::new(&alias))),
                 window: None,
             });

src/query/select.rs

@@ -1,8 +1,11 @@
-use crate::{ColumnTrait, EntityTrait, Iterable, QueryFilter, QueryOrder, QuerySelect, QueryTrait};
+use crate::{
+    cast_enum_as_text, ColumnTrait, EntityTrait, Iterable, QueryFilter, QueryOrder, QuerySelect,
+    QueryTrait,
+};
 use core::fmt::Debug;
 use core::marker::PhantomData;
 pub use sea_query::JoinType;
-use sea_query::{Alias, DynIden, Expr, IntoColumnRef, SeaRc, SelectStatement, SimpleExpr};
+use sea_query::{IntoColumnRef, SelectStatement, SimpleExpr};
 
 /// Defines a structure to perform select operations
 #[derive(Clone, Debug)]
@@ -119,18 +122,8 @@ where
     }
 
     fn column_list(&self) -> Vec<SimpleExpr> {
-        let table = SeaRc::new(E::default()) as DynIden;
-        let text_type = SeaRc::new(Alias::new("text")) as DynIden;
         E::Column::iter()
-            .map(|col| {
-                let expr = Expr::tbl(table.clone(), col);
-                let col_def = col.def();
-                let col_type = col_def.get_column_type();
-                match col_type.get_enum_name() {
-                    Some(_) => expr.as_enum(text_type.clone()),
-                    None => expr.into(),
-                }
-            })
+            .map(|col| cast_enum_as_text(col.into_expr(), &col))
             .collect()
     }
 

src/query/update.rs

@@ -1,9 +1,9 @@
 use crate::{
-    ActiveModelTrait, ColumnTrait, EntityTrait, Iterable, PrimaryKeyToColumn, QueryFilter,
-    QueryTrait,
+    cast_text_as_enum, ActiveModelTrait, ColumnTrait, EntityTrait, Iterable, PrimaryKeyToColumn,
+    QueryFilter, QueryTrait,
 };
 use core::marker::PhantomData;
-use sea_query::{Alias, Expr, IntoIden, SimpleExpr, UpdateStatement};
+use sea_query::{Expr, IntoIden, SimpleExpr, UpdateStatement};
 
 /// Defines a structure to perform UPDATE query operations on a ActiveModel
 #[derive(Clone, Debug)]
@@ -109,13 +109,7 @@ where
             }
             let av = self.model.get(col);
             if av.is_set() {
-                let val = Expr::val(av.into_value().unwrap());
-                let col_def = col.def();
-                let col_type = col_def.get_column_type();
-                let expr = match col_type.get_enum_name() {
-                    Some(enum_name) => val.as_enum(Alias::new(enum_name)),
-                    None => val.into(),
-                };
+                let expr = cast_text_as_enum(Expr::val(av.into_value().unwrap()), &col);
                 self.query.value_expr(col, expr);
             }
         }

src/tests_cfg/lunch_set.rs

@@ -0,0 +1,23 @@
+use super::sea_orm_active_enums::*;
+use crate as sea_orm;
+use crate::entity::prelude::*;
+
+#[derive(Clone, Debug, PartialEq, Eq, DeriveEntityModel)]
+#[sea_orm(table_name = "lunch_set")]
+pub struct Model {
+    #[sea_orm(primary_key)]
+    pub id: i32,
+    pub name: String,
+    pub tea: Tea,
+}
+
+#[derive(Copy, Clone, Debug, EnumIter)]
+pub enum Relation {}
+
+impl RelationTrait for Relation {
+    fn def(&self) -> RelationDef {
+        panic!("No RelationDef")
+    }
+}
+
+impl ActiveModelBehavior for ActiveModel {}

src/tests_cfg/mod.rs

@@ -8,7 +8,9 @@ pub mod entity_linked;
 pub mod filling;
 pub mod fruit;
 pub mod indexes;
+pub mod lunch_set;
 pub mod rust_keyword;
+pub mod sea_orm_active_enums;
 pub mod vendor;
 
 pub use cake::Entity as Cake;
@@ -17,5 +19,6 @@ pub use cake_filling::Entity as CakeFilling;
 pub use cake_filling_price::Entity as CakeFillingPrice;
 pub use filling::Entity as Filling;
 pub use fruit::Entity as Fruit;
+pub use lunch_set::Entity as LunchSet;
 pub use rust_keyword::Entity as RustKeyword;
 pub use vendor::Entity as Vendor;

src/tests_cfg/sea_orm_active_enums.rs

@@ -0,0 +1,11 @@
+use crate as sea_orm;
+use crate::entity::prelude::*;
+
+#[derive(Debug, Clone, PartialEq, Eq, EnumIter, DeriveActiveEnum)]
+#[sea_orm(rs_type = "String", db_type = "Enum", enum_name = "tea")]
+pub enum Tea {
+    #[sea_orm(string_value = "EverydayTea")]
+    EverydayTea,
+    #[sea_orm(string_value = "BreakfastTea")]
+    BreakfastTea,
+}