On Wed, Oct 26, 2022 at 01:38:51PM +0300, David Harel wrote:
[...]
> func errorCheckResult(err error) string {
> if err == nil {
> return ""
> }
> pqerr := err.(*pq.Error)
> switch pqerr.Get('C') {
> case "23505":
> return "Key violation"
> }
> return "Error unknown"
> }
>
> Now I want to be able to test my code thereby generating this type of error
> in the testing function.
> So I need to create an error variable of the type pq.Error and use it as a
> parameter to db.Mock. Something like:
>
> mockDB := wrapper.NewMockQuerier(ctrl)
> // The part that breaks
> err := fmt.Errorf("pq: %s", `duplicate key value violates unique constraint
> "treatment_pk"
> {"Severity":"ERROR","Code":"23505","Message":".....MoreStuff....."}`)
>
> mockDB.EXPECT().AppointmentUpdate(gomock.Any(), gomock.Any()).Return(err)
>
> Any idea?
Well, look at what you do:
fmt.Errorf("pq: %s", `some long text`)
creates a value of some (irrelevant) type implementing the standard interface
error and containing a string which is obtained by calling fmt.Sprintf on the
aguments. The "%s" verb in the format string means "get the string
representation of the matching argument and insert in into the format string
in place of the verb". Your argument is itself a string, and it is completely
opaque to fmt.Errorf - it's taken "as is" and is not interpreted in any way.
Please stop and think of this for a moment: even if the contents of this
string would be somehow interpreted, how would the code in package fmt guess
it has to produce a value of type pg.Error from that string, and how exactly?
So, if you need to create a *pq.Error, go on and do just that in your
mock. Based on [1], you could do something like
return &pq.Error{
Code: "23505",
Severity: "ERROR',
Message: `duplicate key value violates unique constraint "treatment_pk"`,
}
1.
https://github.com/lib/pq/blob/d65e6ae4bdd1c86b16cd6d2bcff4fe970dc697b4/error.go#L25
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/20221026124535.rlmptmaonqsvtsup%40carbon.
