feat: null_safety test

tests/testdata/src/null_safety/negative.go

@@ -0,0 +1,29 @@
+package null_safety
+
+type Order1 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// not nullable - not nullable
+	CustomerId uint `gorm:"not null;foreignKey:CustomerId;"`
+}
+
+type Order2 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// nullable - nullable
+	CustomerId *uint `gorm:"null;foreignKey:CustomerId;"`
+}
+
+type Order3 struct {
+	Id uint `gorm:"primaryKey"`
+	// nullable - unspecified
+	Status      *string
+	Description string
+}
+
+type Order4 struct {
+	Id uint `gorm:"primaryKey"`
+	// not nullable - unspecified
+	Status      *string
+	Description string
+}

tests/testdata/src/null_safety/positive.go

@@ -0,0 +1,29 @@
+package null_safety
+
+type Order5 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// not nullable - nullable
+	CustomerId uint `gorm:"null;foreignKey:CustomerId;"` // want "Null safety error in \"Order5\" model, field \"CustomerId\": column nullable policy doesn't match to tag nullable policy"
+}
+
+type Order6 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// nullable - not nullable
+	CustomerId *uint `gorm:"not null;foreignKey:CustomerId;"` // want "Null safety error in \"Order6\" model, field \"CustomerId\": column nullable policy doesn't match to tag nullable policy"
+}
+
+type Order7 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// not nullable - not nullable, nullable
+	CustomerId uint `gorm:"not null;foreignKey:CustomerId;null;"` // want "Null safety error: tags \"null\" and \"not null\" are specified at one field"
+}
+
+type Order8 struct {
+	Id          uint `gorm:"primaryKey"`
+	Description string
+	// nullable - not nullable, nullable
+	CustomerId *uint `gorm:"not null;foreignKey:CustomerId;null;"` // want "Null safety error: tags \"null\" and \"not null\" are specified at one field"
+}