go-swagger: Models do not show fields from the struct.

Problem statement

calling swagger generate spec -o ./swagger.yaml -m in the go-swagger/fixtures/goparsing/petstore directory produces the following definitions for the models that do not contain the members of the struct.

definitions:
    order:
        title: An Order for one or more pets by a user.
        x-go-name: Order
        x-go-package: github.com/go-swagger/go-swagger/fixtures/goparsing/petstore/models
    pet:
        description: It is used to describe the animals available in the store.
        title: A Pet is the main product in the store.
        x-go-name: Pet
        x-go-package: github.com/go-swagger/go-swagger/fixtures/goparsing/petstore/models
    tag:
        description: It is used to describe the animals available in the store.
        title: A Tag is an extra piece of data to provide more information about a pet.
        x-go-name: Tag
        x-go-package: github.com/go-swagger/go-swagger/fixtures/goparsing/petstore/models
    user:
        description: A User can purchase pets
        x-go-name: User
        x-go-package: github.com/go-swagger/go-swagger/fixtures/goparsing/petstore/models

I would expect that the definition for Order would show the fields and the required ones

// An Order for one or more pets by a user.
// swagger:model order
type Order struct {
	// the ID of the order
	//
	// required: true
	ID int64 `json:"id"`

	// the id of the user who placed the order.
	//
	// required: true
	UserID int64 `json:"userId"`

	// the time at which this order was made.
	//
	// required: true
	OrderedAt strfmt.DateTime `json:"orderedAt"`

	// the items for this order
	// mininum items: 1
	Items []struct {

		// the id of the pet to order
		//
		// required: true
		PetID int64 `json:"petId"`

		// the quantity of this pet to order
		//
		// required: true
		// minimum: 1
		Quantity int32 `json:"qty"`
	} `json:"items"`
}

Am I calling the generation here incorrectly?

Environment

petstore % swagger version version: v0.30.3 commit: ecf6f05b6ecc1b1725c8569534f133fa27e9de6bgo go version go1.19.3 darwin/arm64 OS: macOS