final tweak of proc macro

This commit is contained in:
Joe Ardent 2023-06-14 15:44:54 -07:00
parent f456e07559
commit b59dfb5bf0

View file

@ -5,13 +5,13 @@ use syn::{parse_macro_input, ItemStruct};
#[proc_macro_derive(OptionalOptionalUser)]
pub fn derive_optional_optional_user(input: TokenStream) -> TokenStream {
let input = parse_macro_input!(input as ItemStruct);
let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
let name = &input.ident;
let has_user = input
.fields
.iter()
.find(|f| {
if let Some(ident) = f.ident.clone() {
if let Some(ref ident) = f.ident {
ident == "user"
} else {
false
@ -19,19 +19,25 @@ pub fn derive_optional_optional_user(input: TokenStream) -> TokenStream {
})
.is_some();
let user_is_option_user = if has_user {
let (use_any, user_is_option_user) = if has_user {
(
quote!(
&&::std::any::TypeId::of::<::std::option::Option<crate::User>>() == self.user.type_id()
use ::std::any::Any;
),
quote!(
::std::any::TypeId::of::<::std::option::Option<crate::User>>()
== self.user.type_id()
),
)
} else {
quote!()
(quote!(), quote!(false))
};
let output = quote!(
impl #name {
fn has_optional_user(&self) -> bool {
use ::std::any::Any;
#has_user #user_is_option_user
impl #impl_generics #name #ty_generics #where_clause {
pub fn has_optional_user(&self) -> bool {
#use_any
#user_is_option_user
}
}
);