use proc_macro2::{Span, TokenStream};
use quote::{format_ident, quote};
use syn::{
parse::{Parse, ParseStream},
punctuated::Punctuated,
Fields, ImplGenerics, Index, ItemStruct, LitStr, Path, Token,
};
pub struct IdentifierInput {
pub dollar_crate: Path,
pub id: LitStr,
}
impl Parse for IdentifierInput {
fn parse(input: ParseStream<'_>) -> syn::Result<Self> {
let dollar_crate = input.parse()?;
let _: Token![,] = input.parse()?;
let id = input.parse()?;
Ok(Self { dollar_crate, id })
}
}
pub fn expand_id_zst(input: ItemStruct) -> syn::Result<TokenStream> {
let id = &input.ident;
let owned = format_ident!("Owned{id}");
let owned_decl = expand_owned_id(&input);
let meta = input.attrs.iter().filter(|attr| attr.path().is_ident("ruma_id")).try_fold(
IdZstMeta::default(),
|meta, attr| {
let list: Punctuated<IdZstMeta, Token![,]> =
attr.parse_args_with(Punctuated::parse_terminated)?;
list.into_iter().try_fold(meta, IdZstMeta::merge)
},
)?;
let extra_impls = if let Some(validate) = meta.validate {
expand_checked_impls(&input, validate)
} else {
assert!(
input.generics.params.is_empty(),
"generic unchecked IDs are not currently supported"
);
expand_unchecked_impls(&input)
};
let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
assert_eq!(where_clause, None, "where clauses on identifier types are not currently supported");
let as_str_docs = format!("Creates a string slice from this `{id}`.");
let as_bytes_docs = format!("Creates a byte slice from this `{id}`.");
let as_str_impl = match &input.fields {
Fields::Named(_) | Fields::Unit => {
syn::Error::new(Span::call_site(), "Only tuple structs are supported currently.")
.into_compile_error()
}
Fields::Unnamed(u) => {
let last_idx = Index::from(u.unnamed.len() - 1);
quote! { &self.#last_idx }
}
};
let id_ty = quote! { #id #ty_generics };
let owned_ty = quote! { #owned #ty_generics };
let as_str_impls = expand_as_str_impls(id_ty.clone(), &impl_generics);
let box_partial_eq_string = expand_partial_eq_string(quote! { Box<#id_ty> }, &impl_generics);
Ok(quote! {
#owned_decl
#[automatically_derived]
impl #impl_generics #id_ty {
pub(super) const fn from_borrowed(s: &str) -> &Self {
unsafe { std::mem::transmute(s) }
}
pub(super) fn from_box(s: Box<str>) -> Box<Self> {
unsafe { Box::from_raw(Box::into_raw(s) as _) }
}
pub(super) fn from_rc(s: std::rc::Rc<str>) -> std::rc::Rc<Self> {
unsafe { std::rc::Rc::from_raw(std::rc::Rc::into_raw(s) as _) }
}
pub(super) fn from_arc(s: std::sync::Arc<str>) -> std::sync::Arc<Self> {
unsafe { std::sync::Arc::from_raw(std::sync::Arc::into_raw(s) as _) }
}
pub(super) fn into_owned(self: Box<Self>) -> Box<str> {
unsafe { Box::from_raw(Box::into_raw(self) as _) }
}
#[doc = #as_str_docs]
#[inline]
pub fn as_str(&self) -> &str {
#as_str_impl
}
#[doc = #as_bytes_docs]
#[inline]
pub fn as_bytes(&self) -> &[u8] {
self.as_str().as_bytes()
}
}
#[automatically_derived]
impl #impl_generics Clone for Box<#id_ty> {
fn clone(&self) -> Self {
(**self).into()
}
}
#[automatically_derived]
impl #impl_generics ToOwned for #id_ty {
type Owned = #owned_ty;
fn to_owned(&self) -> Self::Owned {
#owned::from_ref(self)
}
}
#[automatically_derived]
impl #impl_generics AsRef<#id_ty> for #id_ty {
fn as_ref(&self) -> &#id_ty {
self
}
}
#[automatically_derived]
impl #impl_generics AsRef<str> for #id_ty {
fn as_ref(&self) -> &str {
self.as_str()
}
}
#[automatically_derived]
impl #impl_generics AsRef<str> for Box<#id_ty> {
fn as_ref(&self) -> &str {
self.as_str()
}
}
#[automatically_derived]
impl #impl_generics AsRef<[u8]> for #id_ty {
fn as_ref(&self) -> &[u8] {
self.as_bytes()
}
}
#[automatically_derived]
impl #impl_generics AsRef<[u8]> for Box<#id_ty> {
fn as_ref(&self) -> &[u8] {
self.as_bytes()
}
}
#[automatically_derived]
impl #impl_generics From<&#id_ty> for String {
fn from(id: &#id_ty) -> Self {
id.as_str().to_owned()
}
}
#[automatically_derived]
impl #impl_generics From<Box<#id_ty>> for String {
fn from(id: Box<#id_ty>) -> Self {
id.into_owned().into()
}
}
#[automatically_derived]
impl #impl_generics From<&#id_ty> for Box<#id_ty> {
fn from(id: &#id_ty) -> Self {
<#id_ty>::from_box(id.as_str().into())
}
}
#[automatically_derived]
impl #impl_generics From<&#id_ty> for std::rc::Rc<#id_ty> {
fn from(s: &#id_ty) -> std::rc::Rc<#id_ty> {
let rc = std::rc::Rc::<str>::from(s.as_str());
<#id_ty>::from_rc(rc)
}
}
#[automatically_derived]
impl #impl_generics From<&#id_ty> for std::sync::Arc<#id_ty> {
fn from(s: &#id_ty) -> std::sync::Arc<#id_ty> {
let arc = std::sync::Arc::<str>::from(s.as_str());
<#id_ty>::from_arc(arc)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<#id_ty> for Box<#id_ty> {
fn eq(&self, other: &#id_ty) -> bool {
self.as_str() == other.as_str()
}
}
#[automatically_derived]
impl #impl_generics PartialEq<&'_ #id_ty> for Box<#id_ty> {
fn eq(&self, other: &&#id_ty) -> bool {
self.as_str() == other.as_str()
}
}
#[automatically_derived]
impl #impl_generics PartialEq<Box<#id_ty>> for #id_ty {
fn eq(&self, other: &Box<#id_ty>) -> bool {
self.as_str() == other.as_str()
}
}
#[automatically_derived]
impl #impl_generics PartialEq<Box<#id_ty>> for &'_ #id_ty {
fn eq(&self, other: &Box<#id_ty>) -> bool {
self.as_str() == other.as_str()
}
}
#as_str_impls
#box_partial_eq_string
#extra_impls
})
}
fn expand_owned_id(input: &ItemStruct) -> TokenStream {
let id = &input.ident;
let owned = format_ident!("Owned{id}");
let doc_header = format!("Owned variant of {id}");
let (impl_generics, ty_generics, _where_clause) = input.generics.split_for_impl();
let id_ty = quote! { #id #ty_generics };
let owned_ty = quote! { #owned #ty_generics };
let as_str_impls = expand_as_str_impls(owned_ty.clone(), &impl_generics);
quote! {
#[doc = #doc_header]
pub struct #owned #impl_generics {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
inner: Box<#id_ty>,
#[cfg(ruma_identifiers_storage = "Arc")]
inner: std::sync::Arc<#id_ty>,
}
#[automatically_derived]
impl #impl_generics #owned_ty {
fn from_ref(v: &#id_ty) -> Self {
Self {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
inner: #id::from_box(v.as_str().into()),
#[cfg(ruma_identifiers_storage = "Arc")]
inner: #id::from_arc(v.as_str().into()),
}
}
}
#[automatically_derived]
impl #impl_generics AsRef<#id_ty> for #owned_ty {
fn as_ref(&self) -> &#id_ty {
&*self.inner
}
}
#[automatically_derived]
impl #impl_generics AsRef<str> for #owned_ty {
fn as_ref(&self) -> &str {
self.inner.as_str()
}
}
#[automatically_derived]
impl #impl_generics AsRef<[u8]> for #owned_ty {
fn as_ref(&self) -> &[u8] {
self.inner.as_bytes()
}
}
#[automatically_derived]
impl #impl_generics From<#owned_ty> for String {
fn from(id: #owned_ty) -> String {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
{ id.inner.into() }
#[cfg(ruma_identifiers_storage = "Arc")]
{ id.inner.as_ref().into() }
}
}
#[automatically_derived]
impl #impl_generics std::clone::Clone for #owned_ty {
fn clone(&self) -> Self {
(&*self.inner).into()
}
}
#[automatically_derived]
impl #impl_generics std::ops::Deref for #owned_ty {
type Target = #id_ty;
fn deref(&self) -> &Self::Target {
&self.inner
}
}
#[automatically_derived]
impl #impl_generics std::borrow::Borrow<#id_ty> for #owned_ty {
fn borrow(&self) -> &#id_ty {
self.as_ref()
}
}
#[automatically_derived]
impl #impl_generics From<&'_ #id_ty> for #owned_ty {
fn from(id: &#id_ty) -> #owned_ty {
#owned { inner: id.into() }
}
}
#[automatically_derived]
impl #impl_generics From<Box<#id_ty>> for #owned_ty {
fn from(b: Box<#id_ty>) -> #owned_ty {
Self { inner: b.into() }
}
}
#[automatically_derived]
impl #impl_generics From<std::sync::Arc<#id_ty>> for #owned_ty {
fn from(a: std::sync::Arc<#id_ty>) -> #owned_ty {
Self {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
inner: a.as_ref().into(),
#[cfg(ruma_identifiers_storage = "Arc")]
inner: a,
}
}
}
#[automatically_derived]
impl #impl_generics From<#owned_ty> for Box<#id_ty> {
fn from(a: #owned_ty) -> Box<#id_ty> {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
{ a.inner }
#[cfg(ruma_identifiers_storage = "Arc")]
{ a.inner.as_ref().into() }
}
}
#[automatically_derived]
impl #impl_generics From<#owned_ty> for std::sync::Arc<#id_ty> {
fn from(a: #owned_ty) -> std::sync::Arc<#id_ty> {
#[cfg(not(any(ruma_identifiers_storage = "Arc")))]
{ a.inner.into() }
#[cfg(ruma_identifiers_storage = "Arc")]
{ a.inner }
}
}
#[automatically_derived]
impl #impl_generics std::cmp::PartialEq for #owned_ty {
fn eq(&self, other: &Self) -> bool {
self.as_str() == other.as_str()
}
}
#[automatically_derived]
impl #impl_generics std::cmp::Eq for #owned_ty {}
#[automatically_derived]
impl #impl_generics std::cmp::PartialOrd for #owned_ty {
fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
Some(self.cmp(other))
}
}
#[automatically_derived]
impl #impl_generics std::cmp::Ord for #owned_ty {
fn cmp(&self, other: &Self) -> std::cmp::Ordering {
self.as_str().cmp(other.as_str())
}
}
#[automatically_derived]
impl #impl_generics std::hash::Hash for #owned_ty {
fn hash<H>(&self, state: &mut H)
where
H: std::hash::Hasher,
{
self.as_str().hash(state)
}
}
#as_str_impls
#[automatically_derived]
impl #impl_generics PartialEq<#id_ty> for #owned_ty {
fn eq(&self, other: &#id_ty) -> bool {
AsRef::<#id_ty>::as_ref(self) == other
}
}
#[automatically_derived]
impl #impl_generics PartialEq<#owned_ty> for #id_ty {
fn eq(&self, other: &#owned_ty) -> bool {
self == AsRef::<#id_ty>::as_ref(other)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<&#id_ty> for #owned_ty {
fn eq(&self, other: &&#id_ty) -> bool {
AsRef::<#id_ty>::as_ref(self) == *other
}
}
#[automatically_derived]
impl #impl_generics PartialEq<#owned_ty> for &#id_ty {
fn eq(&self, other: &#owned_ty) -> bool {
*self == AsRef::<#id_ty>::as_ref(other)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<Box<#id_ty>> for #owned_ty {
fn eq(&self, other: &Box<#id_ty>) -> bool {
AsRef::<#id_ty>::as_ref(self) == AsRef::<#id_ty>::as_ref(other)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<#owned_ty> for Box<#id_ty> {
fn eq(&self, other: &#owned_ty) -> bool {
AsRef::<#id_ty>::as_ref(self) == AsRef::<#id_ty>::as_ref(other)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<std::sync::Arc<#id_ty>> for #owned_ty {
fn eq(&self, other: &std::sync::Arc<#id_ty>) -> bool {
AsRef::<#id_ty>::as_ref(self) == AsRef::<#id_ty>::as_ref(other)
}
}
#[automatically_derived]
impl #impl_generics PartialEq<#owned_ty> for std::sync::Arc<#id_ty> {
fn eq(&self, other: &#owned_ty) -> bool {
AsRef::<#id_ty>::as_ref(self) == AsRef::<#id_ty>::as_ref(other)
}
}
}
}
fn expand_checked_impls(input: &ItemStruct, validate: Path) -> TokenStream {
let id = &input.ident;
let owned = format_ident!("Owned{id}");
let (impl_generics, ty_generics, _where_clause) = input.generics.split_for_impl();
let generic_params = &input.generics.params;
let parse_doc_header = format!("Try parsing a `&str` into an `Owned{id}`.");
let parse_box_doc_header = format!("Try parsing a `&str` into a `Box<{id}>`.");
let parse_rc_docs = format!("Try parsing a `&str` into an `Rc<{id}>`.");
let parse_arc_docs = format!("Try parsing a `&str` into an `Arc<{id}>`.");
let id_ty = quote! { #id #ty_generics };
let owned_ty = quote! { #owned #ty_generics };
quote! {
#[automatically_derived]
impl #impl_generics #id_ty {
#[doc = #parse_doc_header]
pub fn parse(
s: impl AsRef<str>,
) -> Result<#owned_ty, crate::IdParseError> {
let s = s.as_ref();
#validate(s)?;
Ok(#id::from_borrowed(s).to_owned())
}
#[doc = #parse_box_doc_header]
pub fn parse_box(
s: impl AsRef<str> + Into<Box<str>>,
) -> Result<Box<Self>, crate::IdParseError> {
#validate(s.as_ref())?;
Ok(#id::from_box(s.into()))
}
#[doc = #parse_rc_docs]
pub fn parse_rc(
s: impl AsRef<str> + Into<std::rc::Rc<str>>,
) -> Result<std::rc::Rc<Self>, crate::IdParseError> {
#validate(s.as_ref())?;
Ok(#id::from_rc(s.into()))
}
#[doc = #parse_arc_docs]
pub fn parse_arc(
s: impl AsRef<str> + Into<std::sync::Arc<str>>,
) -> Result<std::sync::Arc<Self>, crate::IdParseError> {
#validate(s.as_ref())?;
Ok(#id::from_arc(s.into()))
}
}
#[automatically_derived]
impl<'de, #generic_params> serde::Deserialize<'de> for Box<#id_ty> {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: serde::Deserializer<'de>,
{
use serde::de::Error;
let s = String::deserialize(deserializer)?;
match #id::parse_box(s) {
Ok(o) => Ok(o),
Err(e) => Err(D::Error::custom(e)),
}
}
}
#[automatically_derived]
impl<'de, #generic_params> serde::Deserialize<'de> for #owned_ty {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: serde::Deserializer<'de>,
{
use serde::de::Error;
let s = String::deserialize(deserializer)?;
match #id::parse(s) {
Ok(o) => Ok(o),
Err(e) => Err(D::Error::custom(e)),
}
}
}
#[automatically_derived]
impl<'a, #generic_params> std::convert::TryFrom<&'a str> for &'a #id_ty {
type Error = crate::IdParseError;
fn try_from(s: &'a str) -> Result<Self, Self::Error> {
#validate(s)?;
Ok(<#id_ty>::from_borrowed(s))
}
}
#[automatically_derived]
impl #impl_generics std::str::FromStr for Box<#id_ty> {
type Err = crate::IdParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
<#id_ty>::parse_box(s)
}
}
#[automatically_derived]
impl #impl_generics std::convert::TryFrom<&str> for Box<#id_ty> {
type Error = crate::IdParseError;
fn try_from(s: &str) -> Result<Self, Self::Error> {
<#id_ty>::parse_box(s)
}
}
#[automatically_derived]
impl #impl_generics std::convert::TryFrom<String> for Box<#id_ty> {
type Error = crate::IdParseError;
fn try_from(s: String) -> Result<Self, Self::Error> {
<#id_ty>::parse_box(s)
}
}
#[automatically_derived]
impl #impl_generics std::str::FromStr for #owned_ty {
type Err = crate::IdParseError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
<#id_ty>::parse(s)
}
}
#[automatically_derived]
impl #impl_generics std::convert::TryFrom<&str> for #owned_ty {
type Error = crate::IdParseError;
fn try_from(s: &str) -> Result<Self, Self::Error> {
<#id_ty>::parse(s)
}
}
#[automatically_derived]
impl #impl_generics std::convert::TryFrom<String> for #owned_ty {
type Error = crate::IdParseError;
fn try_from(s: String) -> Result<Self, Self::Error> {
<#id_ty>::parse(s)
}
}
}
}
fn expand_unchecked_impls(input: &ItemStruct) -> TokenStream {
let id = &input.ident;
let owned = format_ident!("Owned{id}");
quote! {
#[automatically_derived]
impl<'a> From<&'a str> for &'a #id {
fn from(s: &'a str) -> Self {
#id::from_borrowed(s)
}
}
#[automatically_derived]
impl From<&str> for #owned {
fn from(s: &str) -> Self {
<&#id>::from(s).into()
}
}
#[automatically_derived]
impl From<Box<str>> for #owned {
fn from(s: Box<str>) -> Self {
<&#id>::from(&*s).into()
}
}
#[automatically_derived]
impl From<String> for #owned {
fn from(s: String) -> Self {
<&#id>::from(s.as_str()).into()
}
}
#[automatically_derived]
impl From<&str> for Box<#id> {
fn from(s: &str) -> Self {
#id::from_box(s.into())
}
}
#[automatically_derived]
impl From<Box<str>> for Box<#id> {
fn from(s: Box<str>) -> Self {
#id::from_box(s)
}
}
#[automatically_derived]
impl From<String> for Box<#id> {
fn from(s: String) -> Self {
#id::from_box(s.into())
}
}
#[automatically_derived]
impl From<Box<#id>> for Box<str> {
fn from(id: Box<#id>) -> Self {
id.into_owned()
}
}
#[automatically_derived]
impl<'de> serde::Deserialize<'de> for Box<#id> {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: serde::Deserializer<'de>,
{
Box::<str>::deserialize(deserializer).map(#id::from_box)
}
}
#[automatically_derived]
impl<'de> serde::Deserialize<'de> for #owned {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: serde::Deserializer<'de>,
{
Box::<str>::deserialize(deserializer).map(#id::from_box).map(Into::into)
}
}
}
}
fn expand_as_str_impls(ty: TokenStream, impl_generics: &ImplGenerics<'_>) -> TokenStream {
let partial_eq_string = expand_partial_eq_string(ty.clone(), impl_generics);
quote! {
#[automatically_derived]
impl #impl_generics std::fmt::Display for #ty {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self.as_str())
}
}
#[automatically_derived]
impl #impl_generics std::fmt::Debug for #ty {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
<str as std::fmt::Debug>::fmt(self.as_str(), f)
}
}
#[automatically_derived]
impl #impl_generics serde::Serialize for #ty {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
serializer.serialize_str(self.as_str())
}
}
#partial_eq_string
}
}
fn expand_partial_eq_string(ty: TokenStream, impl_generics: &ImplGenerics<'_>) -> TokenStream {
IntoIterator::into_iter([
(ty.clone(), quote! { str }),
(ty.clone(), quote! { &str }),
(ty.clone(), quote! { String }),
(quote! { str }, ty.clone()),
(quote! { &str }, ty.clone()),
(quote! { String }, ty),
])
.map(|(lhs, rhs)| {
quote! {
#[automatically_derived]
impl #impl_generics PartialEq<#rhs> for #lhs {
fn eq(&self, other: &#rhs) -> bool {
AsRef::<str>::as_ref(self)
== AsRef::<str>::as_ref(other)
}
}
}
})
.collect()
}
mod kw {
syn::custom_keyword!(validate);
}
#[derive(Default)]
struct IdZstMeta {
validate: Option<Path>,
}
impl IdZstMeta {
fn merge(self, other: IdZstMeta) -> syn::Result<Self> {
let validate = match (self.validate, other.validate) {
(None, None) => None,
(Some(val), None) | (None, Some(val)) => Some(val),
(Some(a), Some(b)) => {
let mut error = syn::Error::new_spanned(b, "duplicate attribute argument");
error.combine(syn::Error::new_spanned(a, "note: first one here"));
return Err(error);
}
};
Ok(Self { validate })
}
}
impl Parse for IdZstMeta {
fn parse(input: ParseStream<'_>) -> syn::Result<Self> {
let _: kw::validate = input.parse()?;
let _: Token![=] = input.parse()?;
let validate = Some(input.parse()?);
Ok(Self { validate })
}
}