Add default_expr support for ColumnDef (#1474)

* Add default_expr support for ColumnDef

* added test for attribute `default_value`

* Implements `PartialEq` for `sea_query::SimpleExpr`

* RcOrArc

* Re-export `sea_query::Expr` in `sea_orm::entity::prelude`

* Add default_expr support for ColumnDef

* added test for attribute `default_value`

* Implements `PartialEq` for `sea_query::SimpleExpr`

* RcOrArc

* Re-export `sea_query::Expr` in `sea_orm::entity::prelude`

* Deprecate `ColumnDef::default_value()`

* Add `ColumnDef::default()`

---------

Co-authored-by: Billy Chan <ccw.billy.123@gmail.com>

sea-orm-macros/src/derives/entity_model.rs

@@ -137,7 +137,15 @@ pub fn expand_derive_entity_model(data: Data, attrs: Vec<Attribute>) -> syn::Res
                             } else if meta.path.is_ident("default_value") {
                                 default_value = Some(meta.value()?.parse::<Lit>()?);
                             } else if meta.path.is_ident("default_expr") {
-                                default_expr = Some(meta.value()?.parse::<Lit>()?);
+                                let lit = meta.value()?.parse()?;
+                                if let Lit::Str(litstr) = lit {
+                                    let value_expr: TokenStream = syn::parse_str(&litstr.value())?;
+                                    default_expr = Some(value_expr);
+                                } else {
+                                    return Err(
+                                        meta.error(format!("Invalid column_type {:?}", lit))
+                                    );
+                                }
                             } else if meta.path.is_ident("column_name") {
                                 let lit = meta.value()?.parse()?;
                                 if let Lit::Str(litstr) = lit {
@@ -264,10 +272,10 @@ pub fn expand_derive_entity_model(data: Data, attrs: Vec<Attribute>) -> syn::Res
                         match_row = quote! { #match_row.unique() };
                     }
                     if let Some(default_value) = default_value {
-                        match_row = quote! { #match_row.default_value(#default_value) };
+                        match_row = quote! { #match_row.default(#default_value) };
                     }
                     if let Some(default_expr) = default_expr {
-                        match_row = quote! { #match_row.default_expr(#default_expr) };
+                        match_row = quote! { #match_row.default(#default_expr) };
                     }
                     columns_trait.push(match_row);
                 }

src/entity/column.rs

@@ -15,7 +15,7 @@ pub struct ColumnDef {
     pub(crate) null: bool,
     pub(crate) unique: bool,
     pub(crate) indexed: bool,
-    pub(crate) default_value: Option<Value>,
+    pub(crate) default: Option<SimpleExpr>,
 }
 
 macro_rules! bind_oper {
@@ -310,7 +310,7 @@ impl ColumnTypeTrait for ColumnType {
             null: false,
             unique: false,
             indexed: false,
-            default_value: None,
+            default: None,
         }
     }
 
@@ -362,11 +362,21 @@ impl ColumnDef {
     }
 
     /// Set the default value
+    #[deprecated(since = "0.12.0", note = "Please use [`ColumnDef::default`]")]
     pub fn default_value<T>(mut self, value: T) -> Self
     where
         T: Into<Value>,
     {
-        self.default_value = Some(value.into());
+        self.default = Some(value.into().into());
+        self
+    }
+
+    /// Set the default value or expression of a column
+    pub fn default<T>(mut self, default: T) -> Self
+    where
+        T: Into<SimpleExpr>,
+    {
+        self.default = Some(default.into());
         self
     }
 
@@ -493,7 +503,7 @@ mod tests {
     #[test]
     #[cfg(feature = "macros")]
     fn entity_model_column_1() {
-        use crate::entity::*;
+        use crate::prelude::*;
 
         mod hello {
             use crate as sea_orm;
@@ -521,6 +531,12 @@ mod tests {
                 pub eight: u32,
                 #[sea_orm(unique, indexed, nullable)]
                 pub nine: u64,
+                #[sea_orm(default_expr = "Expr::current_timestamp()")]
+                pub ten: DateTimeUtc,
+                #[sea_orm(default_value = 7)]
+                pub eleven: u8,
+                #[sea_orm(default_value = "twelve_value")]
+                pub twelve: String,
             }
 
             #[derive(Copy, Clone, Debug, EnumIter, DeriveRelation)]
@@ -562,6 +578,20 @@ mod tests {
             hello::Column::Nine.def(),
             ColumnType::BigUnsigned.def().unique().indexed().nullable()
         );
+        assert_eq!(
+            hello::Column::Ten.def(),
+            ColumnType::TimestampWithTimeZone
+                .def()
+                .default(Expr::current_timestamp())
+        );
+        assert_eq!(
+            hello::Column::Eleven.def(),
+            ColumnType::TinyUnsigned.def().default(7)
+        );
+        assert_eq!(
+            hello::Column::Twelve.def(),
+            ColumnType::String(None).def().default("twelve_value")
+        );
     }
 
     #[test]

src/entity/prelude.rs

@@ -1,6 +1,6 @@
 pub use crate::{
     error::*,
-    sea_query::{BlobSize, DynIden, RcOrArc, SeaRc},
+    sea_query::{BlobSize, DynIden, Expr, RcOrArc, SeaRc},
     ActiveEnum, ActiveModelBehavior, ActiveModelTrait, ColumnDef, ColumnTrait, ColumnType,
     ColumnTypeTrait, ConnectionTrait, CursorTrait, DatabaseConnection, DbConn, EntityName,
     EntityTrait, EnumIter, ForeignKeyAction, Iden, IdenStatic, Linked, LoaderTrait, ModelTrait,

src/schema/entity.rs

@@ -210,8 +210,8 @@ where
     if orm_column_def.unique {
         column_def.unique_key();
     }
-    if let Some(value) = orm_column_def.default_value {
-        column_def.default(value);
+    if let Some(default) = orm_column_def.default {
+        column_def.default(default);
     }
     for primary_key in E::PrimaryKey::iter() {
         if column.to_string() == primary_key.into_column().to_string() {