Breaking change since v1.24.4: Custom serializer on nil-slices

[maja42]

I already reported this at https://github.com/go-gorm/postgres/issues/159 a while ago, but it was ignored until now, probably because it's an issue in gorm itself. Since it's turning more and more into an issue for me, I decided to report it here as well:

go (simplified):

type ArgumentList []interface{}   // custom slice-type

// Never called, if `a` is nil (since v1.24.4):
func (a ArgumentList) Value() (driver.Value, error) {
    js, _ := a.MarshalJSON() // Returns a json-array. Nil-slices return "[]".
    return datatypes.JSON(js).Value()
}

func (a *ArgumentList) Scan(value interface{}) error {
    var js datatypes.JSON
    js.Scan(value)
    return json.Unmarshal(js, a)
}

Before 1.4.6, my serializers converted nil-slices to empty json-arrays ([] string). Now, they are ignored, nil gets converted into a PostgreSQL null, and my not-null-constraints are triggered. This prevents me from updating the gorm-dependency.

[maja42]

The "workaround" for this (to support go get -u ./... in go modules) gets longer with each new gorm version:

in go.mod:

exclude gorm.io/gorm v1.24.4
exclude gorm.io/gorm v1.24.5
exclude gorm.io/gorm v1.24.6
exclude gorm.io/gorm v1.24.7
exclude gorm.io/gorm v1.25.0
exclude gorm.io/gorm v1.25.1

exclude gorm.io/driver/postgres v1.4.6
exclude gorm.io/driver/postgres v1.4.7
exclude gorm.io/driver/postgres v1.4.8
exclude gorm.io/driver/postgres v1.5.0

[github-actions[bot]]

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[black-06]

This is related to the postgres-driver, see https://github.com/jackc/pgx/issues/1566 for more infomation.

[github-actions[bot]]

This issue has been automatically marked as stale because it has been open 360 days with no activity. Remove stale label or comment or this will be closed in 180 days