entc/gen: allow setting default-func for id fields (#1290)

entc/gen/type.go

@@ -738,7 +738,7 @@ func (t *Type) checkField(tf *Field, f *load.Field) (err error) {
 		err = fmt.Errorf("invalid type for field %s", f.Name)
 	case f.Nillable && !f.Optional:
 		err = fmt.Errorf("nillable field %q must be optional", f.Name)
-	case f.Unique && f.Default && f.Info.Type != field.TypeUUID:
+	case f.Unique && f.Default && f.DefaultKind != reflect.Func:
 		err = fmt.Errorf("unique field %q cannot have default value", f.Name)
 	case t.fields[f.Name] != nil:
 		err = fmt.Errorf("field %q redeclared for type %q", f.Name, t.Name)

entc/integration/customid/ent/migrate/schema.go

@@ -38,7 +38,7 @@ var (
 		{Name: "before_id", Type: field.TypeFloat64, Nullable: true},
 		{Name: "after_id", Type: field.TypeFloat64, Nullable: true},
 		{Name: "model", Type: field.TypeString},
-		{Name: "pet_cars", Type: field.TypeString, Nullable: true, Size: 25},
+		{Name: "pet_cars", Type: field.TypeString, Nullable: true, Size: 36},
 	}
 	// CarsTable holds the schema information for the "cars" table.
 	CarsTable = &schema.Table{
@@ -102,8 +102,8 @@ var (
 	}
 	// PetsColumns holds the columns for the "pets" table.
 	PetsColumns = []*schema.Column{
-		{Name: "id", Type: field.TypeString, Unique: true, Size: 25},
-		{Name: "pet_best_friend", Type: field.TypeString, Unique: true, Nullable: true, Size: 25},
+		{Name: "id", Type: field.TypeString, Unique: true, Size: 36},
+		{Name: "pet_best_friend", Type: field.TypeString, Unique: true, Nullable: true, Size: 36},
 		{Name: "user_pets", Type: field.TypeInt, Nullable: true},
 	}
 	// PetsTable holds the schema information for the "pets" table.
@@ -197,8 +197,8 @@ var (
 	}
 	// PetFriendsColumns holds the columns for the "pet_friends" table.
 	PetFriendsColumns = []*schema.Column{
-		{Name: "pet_id", Type: field.TypeString, Size: 25},
-		{Name: "friend_id", Type: field.TypeString, Size: 25},
+		{Name: "pet_id", Type: field.TypeString, Size: 36},
+		{Name: "friend_id", Type: field.TypeString, Size: 36},
 	}
 	// PetFriendsTable holds the schema information for the "pet_friends" table.
 	PetFriendsTable = &schema.Table{

entc/integration/customid/ent/pet/pet.go

@@ -80,6 +80,8 @@ func ValidColumn(column string) bool {
 }
 
 var (
+	// DefaultID holds the default value on creation for the "id" field.
+	DefaultID func() string
 	// IDValidator is a validator for the "id" field. It is called by the builders before save.
 	IDValidator func(string) error
 )

entc/integration/customid/ent/pet_create.go

@@ -30,6 +30,14 @@ func (pc *PetCreate) SetID(s string) *PetCreate {
 	return pc
 }
 
+// SetNillableID sets the "id" field if the given value is not nil.
+func (pc *PetCreate) SetNillableID(s *string) *PetCreate {
+	if s != nil {
+		pc.SetID(*s)
+	}
+	return pc
+}
+
 // SetOwnerID sets the "owner" edge to the User entity by ID.
 func (pc *PetCreate) SetOwnerID(id int) *PetCreate {
 	pc.mutation.SetOwnerID(id)
@@ -109,6 +117,7 @@ func (pc *PetCreate) Save(ctx context.Context) (*Pet, error) {
 		err  error
 		node *Pet
 	)
+	pc.defaults()
 	if len(pc.hooks) == 0 {
 		if err = pc.check(); err != nil {
 			return nil, err
@@ -147,6 +156,14 @@ func (pc *PetCreate) SaveX(ctx context.Context) *Pet {
 	return v
 }
 
+// defaults sets the default values of the builder before save.
+func (pc *PetCreate) defaults() {
+	if _, ok := pc.mutation.ID(); !ok {
+		v := pet.DefaultID()
+		pc.mutation.SetID(v)
+	}
+}
+
 // check runs all checks and user-defined validators on the builder.
 func (pc *PetCreate) check() error {
 	if v, ok := pc.mutation.ID(); ok {
@@ -276,6 +293,7 @@ func (pcb *PetCreateBulk) Save(ctx context.Context) ([]*Pet, error) {
 	for i := range pcb.builders {
 		func(i int, root context.Context) {
 			builder := pcb.builders[i]
+			builder.defaults()
 			var mut Mutator = MutateFunc(func(ctx context.Context, m Mutation) (Value, error) {
 				mutation, ok := m.(*PetMutation)
 				if !ok {

entc/integration/customid/ent/runtime.go

@@ -59,6 +59,8 @@ func init() {
 	_ = petFields
 	// petDescID is the schema descriptor for id field.
 	petDescID := petFields[0].Descriptor()
+	// pet.DefaultID holds the default value on creation for the id field.
+	pet.DefaultID = petDescID.Default.(func() string)
 	// pet.IDValidator is a validator for the "id" field. It is called by the builders before save.
 	pet.IDValidator = func() func(string) error {
 		validators := petDescID.Validators

entc/integration/customid/ent/schema/pet.go

@@ -8,6 +8,7 @@ import (
 	"entgo.io/ent"
 	"entgo.io/ent/schema/edge"
 	"entgo.io/ent/schema/field"
+	"github.com/google/uuid"
 )
 
 // Pet holds the schema definition for the Pet entity.
@@ -19,10 +20,11 @@ type Pet struct {
 func (Pet) Fields() []ent.Field {
 	return []ent.Field{
 		field.String("id").
-			MaxLen(25).
+			MaxLen(36).
 			NotEmpty().
 			Unique().
-			Immutable(),
+			Immutable().
+			DefaultFunc(uuid.NewString),
 	}
 }