Wrap Scan errors

[injeniero]

Here the returned error from the scanner is converted to string, I would like it to be wrapped so you can search for it later using errors.Is
https://github.com/jackc/pgx/blob/master/pgtype/pgtype.go#L2048

- return fmt.Errorf("unable to encode %#v into %s format for %s (OID %d): %s", value, format, dataTypeName, oid, err)
+ return fmt.Errorf("unable to encode %#v into %s format for %s (OID %d): %w", value, format, dataTypeName, oid, err)

This would be used like:

func (s *MyType) Scan(value interface{}) error {
	if value == nil {
		return nil
	}
	...

	return fmt.Errorf("unknown type: %s, %w", value, ErrInvalidMyType)
}

then somewhere else in the code:

db.Insert(ctx, myType)
if errors.Is(err, ErrInvalidProductSupport) {
   //do something for this special case
} else {
   // unknown error type
}

[jackc]

Seems reasonable.

[injeniero]

@jackc what would be the next step to get this done?

Thanks!

[jackc]

You can create a PR.

[injeniero]

PR created: #1573