IntelliJ Go type inference failing

I'm having an issue where both IntelliJ and Goland type inference fails.

The code compiles, runs through various go linters and go formatters fine, but IntelliJ claims it is not valid type inference. Have commented on the row where type inference fails.


package main

type UserCreated struct {
    UserID   string `json:"event_id"`
    Username  string `json:"username"`
}

type UserProfilePictureUpdated struct {
    UserID string `json:"event_id"`
    PictureURL string `json:"picture_url"`
}

// Marker interface
type ProjectionHandlers[TState any] interface {
    IsEventHandlers()
}

type UserProjectionHandlers[TState any] interface {
    ProjectionHandlers[TState]

    UserCreated(state TState, event UserCreated) (TState, error)
    UserProfilePictureUpdated(state TState, event UserProfilePictureUpdated) (TState, error)
}



type Projector[TEventHandlers ProjectionHandlers[TState], TState any] struct {
    initialState TState
    handlers     TEventHandlers
}

func NewEventProcessor[TEventHandlers ProjectionHandlers[TState], TState any](
    initialState TState,
    handlers TEventHandlers,
) *Projector[TEventHandlers, TState] {
    return &Projector[TEventHandlers, TState]{
       initialState: initialState,
       handlers:     handlers,
    }
}

type UserProjector[THandlers UserProjectionHandlers[TState], TState any] = Projector[THandlers, TState]

func NewUserProjector[THandlers UserProjectionHandlers[TState], TState any](
    initialState TState,
    handlers THandlers,
) *UserProjector[THandlers, TState] {
    // This fails type conversion in IntelliJ
    // Cannot use 'NewEventProcessor(initialState, handlers)' (type *Projector[TEventHandlers, TState]) as the type *UserProjector[THandlers, TState]
    return NewEventProcessor(initialState, handlers)
    
    // THe below works 
    //return (*UserProjector[THandlers, TState])(NewEventProcessor(initialState, handlers))
}


type UserNameProjectionState struct {
    Username string `json:"username"`
}

type UserNameProjectorHandlers struct{}
// IsCategoryHandler implements the CategoryHandlers marker interface
func (h UserNameProjectorHandlers) IsEventHandlers() {}

func NewUserNameProjectorHandlers() UserNameProjectorHandlers {
    return UserNameProjectorHandlers{}
}


func (h UserNameProjectorHandlers) UserCreated(
    state UserNameProjectionState,
    event UserCreated,
) (UserNameProjectionState, error) {
    // Initialize the user in the map
    state.Username = event.Username
    return state, nil
}

func (h UserNameProjectorHandlers) UserProfilePictureUpdated(
    state UserNameProjectionState,
    _ UserProfilePictureUpdated,
) (UserNameProjectionState, error) {
    return state, nil
}

type UserNameProjector = UserProjector[UserNameProjectorHandlers, UserNameProjectionState]

func NewUserNameProjector() *UserNameProjector {
    initialState := UserNameProjectionState{
       Username: "",
    }
    handlers := NewUserNameProjectorHandlers()

    return NewUserProjector(initialState, handlers)
}


func main() {
    // Example usage
    projector := NewUserNameProjector()

    // create a UserCreated event
    event := UserCreated{
       UserID:   "123",
       Username: "john_doe",
    }
    state, err := projector.handlers.UserCreated(projector.initialState, event)

    if err != nil {
       panic(err)
    }
    println("Name:", state.Username)

}