feat: many-to-one check, constrints check

tests/testdata/src/relations_check/positive.go

@@ -2,20 +2,39 @@ package relations_check
 
 type Student struct {
 	Id      uint     `gorm:"primaryKey"`
-	Courses []Course `gorm:"many2many:student_courses;"`
+	Courses []Course `gorm:"many2many:student_courses;constraint:OnDelete:CASCADE;"`
 }
 
 type Course struct {
 	Id       uint     `gorm:"primaryKey"`
-	Students []Course `gorm:"many2many:student_courses;"` // want "Invalid type `Course` in M2M relation \\(use \\[\\]\\*Student or self-reference\\)"
+	Students []Course `gorm:"many2many:student_courses;constraint:OnDelete:CASCADE"` // want "Invalid type `Course` in M2M relation \\(use \\[\\]\\*Student or self-reference\\)"
 }
 
 type Author struct {
 	Id       uint      `gorm:"primaryKey"`
-	Articles []Article `gorm:"many2many:author_articles;"`
+	Articles []Article `gorm:"many2many:author_articles;constraint:OnDelete:CASCADES;"`
 }
 
 type Article struct {
 	Id      uint   `gorm:"primaryKey"`
-	Authors Author `gorm:"many2many:author_articles;"` // want "M2M relation `author_articles` with bad type `Author` \\(should be a slice\\)"
+	Authors Author `gorm:"many2many:author_articles;constraint:OnDelete:CASCADE;"` // want "M2M relation `author_articles` with bad type `Author` \\(should be a slice\\)"
+}
+
+type Kuzbass struct {
+	Id     uint   `gorm:"primaryKey"`
+	Cities []City // want "Expected foreignKey `KuzbassId` in model `City` for 1:M relation with model `Kuzbass`"
+}
+
+type City struct {
+	Id      uint `gorm:"primaryKey"`
+	Kuzbass Kuzbass
+}
+
+type Federation struct {
+	Lands []Land `gorm:"constraint:OnDelete:CASCADE;"` // want ""
+}
+
+type Land struct {
+	Id           uint `gorm:"primaryKey"`
+	FederationId uint
 }