-#![recursion_limit="256"]
-#![cfg_attr(feature = "nightly", feature(proc_macro_diagnostic))]
+#![recursion_limit = "256"]
-extern crate syn;
extern crate proc_macro;
-extern crate proc_macro2;
-extern crate quote;
+use darling::*;
use proc_macro::TokenStream;
-use proc_macro2::{TokenStream as SynTokenStream, Literal};
-use syn::*;
-use syn::export::Span;
-use syn::spanned::Spanned;
+use proc_macro2::{Literal, Span, TokenStream as SynTokenStream};
use quote::*;
+use std::{collections::HashSet, fmt::Display};
+use syn::spanned::Spanned;
+use syn::{Error, Result, *};
+
+/// Helper function for emitting compile errors.
+fn error<T>(span: Span, message: impl Display) -> Result<T> {
+ Err(Error::new(span, message))
+}
-#[cfg(feature = "nightly")]
-fn error(span: Span, data: &str) -> TokenStream {
- span.unstable().error(data).emit();
- TokenStream::new()
+/// Decodes the custom attributes for our custom derive.
+#[derive(FromDeriveInput, Default)]
+#[darling(attributes(enumset), default)]
+struct EnumsetAttrs {
+ no_ops: bool,
+ no_super_impls: bool,
+ #[darling(default)]
+ repr: Option<String>,
+ serialize_as_list: bool,
+ serialize_deny_unknown: bool,
+ #[darling(default)]
+ serialize_repr: Option<String>,
+ #[darling(default)]
+ crate_name: Option<String>,
}
-#[cfg(not(feature = "nightly"))]
-fn error(_: Span, data: &str) -> TokenStream {
- panic!("{}", data)
+/// An variant in the enum set type.
+struct EnumSetValue {
+ /// The name of the variant.
+ name: Ident,
+ /// The discriminant of the variant.
+ variant_repr: u32,
}
-fn enum_set_type_impl(
- name: &Ident, all_variants: u128, repr: Ident,
- no_ops: bool, no_derives: bool, _serialize_as_list: bool,
-) -> SynTokenStream {
- let typed_enumset = quote!(::enumset::EnumSet<#name>);
- let core = quote!(::enumset::internal::core);
+/// Stores information about the enum set type.
+#[allow(dead_code)]
+struct EnumSetInfo {
+ /// The name of the enum.
+ name: Ident,
+ /// The crate name to use.
+ crate_name: Option<Ident>,
+ /// The numeric type to represent the `EnumSet` as in memory.
+ explicit_mem_repr: Option<Ident>,
+ /// The numeric type to serialize the enum as.
+ explicit_serde_repr: Option<Ident>,
+ /// Whether the underlying repr of the enum supports negative values.
+ has_signed_repr: bool,
+ /// Whether the underlying repr of the enum supports values higher than 2^32.
+ has_large_repr: bool,
+ /// A list of variants in the enum.
+ variants: Vec<EnumSetValue>,
+
+ /// The highest encountered variant discriminant.
+ max_discrim: u32,
+ /// The current variant discriminant. Used to track, e.g. `A=10,B,C`.
+ cur_discrim: u32,
+ /// A list of variant names that are already in use.
+ used_variant_names: HashSet<String>,
+ /// A list of variant discriminants that are already in use.
+ used_discriminants: HashSet<u32>,
+
+ /// Avoid generating operator overloads on the enum type.
+ no_ops: bool,
+ /// Avoid generating implementations for `Clone`, `Copy`, `Eq`, and `PartialEq`.
+ no_super_impls: bool,
+ /// Serialize the enum as a list.
+ serialize_as_list: bool,
+ /// Disallow unknown bits while deserializing the enum.
+ serialize_deny_unknown: bool,
+}
+impl EnumSetInfo {
+ fn new(input: &DeriveInput, attrs: EnumsetAttrs) -> EnumSetInfo {
+ EnumSetInfo {
+ name: input.ident.clone(),
+ crate_name: attrs.crate_name.map(|x| Ident::new(&x, Span::call_site())),
+ explicit_mem_repr: attrs.repr.map(|x| Ident::new(&x, Span::call_site())),
+ explicit_serde_repr: attrs
+ .serialize_repr
+ .map(|x| Ident::new(&x, Span::call_site())),
+ has_signed_repr: false,
+ has_large_repr: false,
+ variants: Vec::new(),
+ max_discrim: 0,
+ cur_discrim: 0,
+ used_variant_names: HashSet::new(),
+ used_discriminants: HashSet::new(),
+ no_ops: attrs.no_ops,
+ no_super_impls: attrs.no_super_impls,
+ serialize_as_list: attrs.serialize_as_list,
+ serialize_deny_unknown: attrs.serialize_deny_unknown,
+ }
+ }
+
+ /// Sets an explicit repr for the enumset.
+ fn push_explicit_repr(&mut self, attr_span: Span, repr: &str) -> Result<()> {
+ // Check whether the repr is supported, and if so, set some flags for better error
+ // messages later on.
+ match repr {
+ "Rust" | "C" | "u8" | "u16" | "u32" => Ok(()),
+ "usize" | "u64" | "u128" => {
+ self.has_large_repr = true;
+ Ok(())
+ }
+ "i8" | "i16" | "i32" => {
+ self.has_signed_repr = true;
+ Ok(())
+ }
+ "isize" | "i64" | "i128" => {
+ self.has_signed_repr = true;
+ self.has_large_repr = true;
+ Ok(())
+ }
+ _ => error(attr_span, "Unsupported repr."),
+ }
+ }
+ /// Adds a variant to the enumset.
+ fn push_variant(&mut self, variant: &Variant) -> Result<()> {
+ if self.used_variant_names.contains(&variant.ident.to_string()) {
+ error(variant.span(), "Duplicated variant name.")
+ } else if let Fields::Unit = variant.fields {
+ // Parse the discriminant.
+ if let Some((_, expr)) = &variant.discriminant {
+ let discriminant_fail_message = format!(
+ "Enum set discriminants must be `u32`s.{}",
+ if self.has_signed_repr || self.has_large_repr {
+ format!(
+ " ({} discrimiants are still unsupported with reprs that allow them.)",
+ if self.has_large_repr {
+ "larger"
+ } else if self.has_signed_repr {
+ "negative"
+ } else {
+ "larger or negative"
+ }
+ )
+ } else {
+ String::new()
+ },
+ );
+ if let Expr::Lit(ExprLit { lit: Lit::Int(i), .. }) = expr {
+ match i.base10_parse() {
+ Ok(val) => self.cur_discrim = val,
+ Err(_) => error(expr.span(), &discriminant_fail_message)?,
+ }
+ } else {
+ error(variant.span(), &discriminant_fail_message)?;
+ }
+ }
+
+ // Validate the discriminant.
+ let discriminant = self.cur_discrim;
+ if discriminant >= 128 {
+ let message = if self.variants.len() <= 127 {
+ "`#[derive(EnumSetType)]` currently only supports discriminants up to 127."
+ } else {
+ "`#[derive(EnumSetType)]` currently only supports enums up to 128 variants."
+ };
+ error(variant.span(), message)?;
+ }
+ if self.used_discriminants.contains(&discriminant) {
+ error(variant.span(), "Duplicated enum discriminant.")?;
+ }
+
+ // Add the variant to the info.
+ self.cur_discrim += 1;
+ if discriminant > self.max_discrim {
+ self.max_discrim = discriminant;
+ }
+ self.variants
+ .push(EnumSetValue { name: variant.ident.clone(), variant_repr: discriminant });
+ self.used_variant_names.insert(variant.ident.to_string());
+ self.used_discriminants.insert(discriminant);
+
+ Ok(())
+ } else {
+ error(variant.span(), "`#[derive(EnumSetType)]` can only be used on fieldless enums.")
+ }
+ }
+ /// Validate the enumset type.
+ fn validate(&self) -> Result<()> {
+ fn do_check(ty: &str, max_discrim: u32, what: &str) -> Result<()> {
+ let is_overflowed = match ty {
+ "u8" => max_discrim >= 8,
+ "u16" => max_discrim >= 16,
+ "u32" => max_discrim >= 32,
+ "u64" => max_discrim >= 64,
+ "u128" => max_discrim >= 128,
+ _ => error(
+ Span::call_site(),
+ format!(
+ "Only `u8`, `u16`, `u32`, `u64` and `u128` are supported for {}.",
+ what
+ ),
+ )?,
+ };
+ if is_overflowed {
+ error(Span::call_site(), format!("{} cannot be smaller than bitset.", what))?;
+ }
+ Ok(())
+ }
+
+ // Check if all bits of the bitset can fit in the serialization representation.
+ if let Some(explicit_serde_repr) = &self.explicit_serde_repr {
+ do_check(&explicit_serde_repr.to_string(), self.max_discrim, "serialize_repr")?;
+ }
+
+ // Check if all bits of the bitset can fit in the memory representation, if one was given.
+ if let Some(explicit_mem_repr) = &self.explicit_mem_repr {
+ do_check(&explicit_mem_repr.to_string(), self.max_discrim, "repr")?;
+ }
+ Ok(())
+ }
+
+ /// Computes the underlying type used to store the enumset.
+ fn enumset_repr(&self) -> SynTokenStream {
+ if let Some(explicit_mem_repr) = &self.explicit_mem_repr {
+ explicit_mem_repr.to_token_stream()
+ } else if self.max_discrim <= 7 {
+ quote! { u8 }
+ } else if self.max_discrim <= 15 {
+ quote! { u16 }
+ } else if self.max_discrim <= 31 {
+ quote! { u32 }
+ } else if self.max_discrim <= 63 {
+ quote! { u64 }
+ } else if self.max_discrim <= 127 {
+ quote! { u128 }
+ } else {
+ panic!("max_variant > 127?")
+ }
+ }
+ /// Computes the underlying type used to serialize the enumset.
#[cfg(feature = "serde")]
- let serde = quote!(::enumset::internal::serde);
+ fn serde_repr(&self) -> SynTokenStream {
+ if let Some(serde_repr) = &self.explicit_serde_repr {
+ quote! { #serde_repr }
+ } else {
+ self.enumset_repr()
+ }
+ }
+
+ /// Returns a bitmask of all variants in the set.
+ fn all_variants(&self) -> u128 {
+ let mut accum = 0u128;
+ for variant in &self.variants {
+ assert!(variant.variant_repr <= 127);
+ accum |= 1u128 << variant.variant_repr as u128;
+ }
+ accum
+ }
+}
+
+/// Generates the actual `EnumSetType` impl.
+fn enum_set_type_impl(info: EnumSetInfo) -> SynTokenStream {
+ let name = &info.name;
+
+ let enumset = match &info.crate_name {
+ Some(crate_name) => quote!(::#crate_name),
+ None => {
+ #[cfg(feature = "proc-macro-crate")]
+ {
+ use proc_macro_crate::FoundCrate;
+
+ let crate_name = proc_macro_crate::crate_name("enumset");
+ match crate_name {
+ Ok(FoundCrate::Name(name)) => {
+ let ident = Ident::new(&name, Span::call_site());
+ quote!(::#ident)
+ }
+ _ => quote!(::enumset),
+ }
+ }
+
+ #[cfg(not(feature = "proc-macro-crate"))]
+ {
+ quote!(::enumset)
+ }
+ }
+ };
+ let typed_enumset = quote!(#enumset::EnumSet<#name>);
+ let core = quote!(#enumset::__internal::core_export);
- // proc_macro2 does not support creating u128 literals.
- let all_variants = Literal::u128_unsuffixed(all_variants);
+ let repr = info.enumset_repr();
+ let all_variants = Literal::u128_unsuffixed(info.all_variants());
- let ops = if no_ops {
+ let ops = if info.no_ops {
quote! {}
} else {
quote! {
impl <O : Into<#typed_enumset>> #core::ops::Sub<O> for #name {
type Output = #typed_enumset;
fn sub(self, other: O) -> Self::Output {
- ::enumset::EnumSet::only(self) - other.into()
+ #enumset::EnumSet::only(self) - other.into()
}
}
impl <O : Into<#typed_enumset>> #core::ops::BitAnd<O> for #name {
type Output = #typed_enumset;
fn bitand(self, other: O) -> Self::Output {
- ::enumset::EnumSet::only(self) & other.into()
+ #enumset::EnumSet::only(self) & other.into()
}
}
impl <O : Into<#typed_enumset>> #core::ops::BitOr<O> for #name {
type Output = #typed_enumset;
fn bitor(self, other: O) -> Self::Output {
- ::enumset::EnumSet::only(self) | other.into()
+ #enumset::EnumSet::only(self) | other.into()
}
}
impl <O : Into<#typed_enumset>> #core::ops::BitXor<O> for #name {
type Output = #typed_enumset;
fn bitxor(self, other: O) -> Self::Output {
- ::enumset::EnumSet::only(self) ^ other.into()
+ #enumset::EnumSet::only(self) ^ other.into()
}
}
impl #core::ops::Not for #name {
type Output = #typed_enumset;
fn not(self) -> Self::Output {
- !::enumset::EnumSet::only(self)
+ !#enumset::EnumSet::only(self)
}
}
impl #core::cmp::PartialEq<#typed_enumset> for #name {
fn eq(&self, other: &#typed_enumset) -> bool {
- ::enumset::EnumSet::only(*self) == *other
- }
- }
- }
- };
-
- let derives = if no_derives {
- quote! {}
- } else {
- quote! {
- impl #core::cmp::PartialOrd for #name {
- fn partial_cmp(&self, other: &Self) -> #core::option::Option<#core::cmp::Ordering> {
- (*self as u8).partial_cmp(&(*other as u8))
- }
- }
- impl #core::cmp::Ord for #name {
- fn cmp(&self, other: &Self) -> #core::cmp::Ordering {
- (*self as u8).cmp(&(*other as u8))
- }
- }
- impl #core::cmp::PartialEq for #name {
- fn eq(&self, other: &Self) -> bool {
- (*self as u8) == (*other as u8)
+ #enumset::EnumSet::only(*self) == *other
}
}
- impl #core::cmp::Eq for #name { }
- impl #core::hash::Hash for #name {
- fn hash<H: #core::hash::Hasher>(&self, state: &mut H) {
- state.write_u8(*self as u8)
- }
- }
- impl #core::clone::Clone for #name {
- fn clone(&self) -> Self {
- *self
- }
- }
- impl #core::marker::Copy for #name { }
}
};
#[cfg(feature = "serde")]
- let expecting_str = format!("a list of {}", name);
+ let serde = quote!(#enumset::__internal::serde);
#[cfg(feature = "serde")]
- let serde_ops = if _serialize_as_list {
+ let serde_ops = if info.serialize_as_list {
+ let expecting_str = format!("a list of {}", name);
quote! {
fn serialize<S: #serde::Serializer>(
- set: ::enumset::EnumSet<#name>, ser: S,
+ set: #enumset::EnumSet<#name>, ser: S,
) -> #core::result::Result<S::Ok, S::Error> {
use #serde::ser::SerializeSeq;
let mut seq = ser.serialize_seq(#core::prelude::v1::Some(set.len()))?;
}
fn deserialize<'de, D: #serde::Deserializer<'de>>(
de: D,
- ) -> #core::result::Result<::enumset::EnumSet<#name>, D::Error> {
+ ) -> #core::result::Result<#enumset::EnumSet<#name>, D::Error> {
struct Visitor;
impl <'de> #serde::de::Visitor<'de> for Visitor {
- type Value = ::enumset::EnumSet<#name>;
+ type Value = #enumset::EnumSet<#name>;
fn expecting(
&self, formatter: &mut #core::fmt::Formatter,
) -> #core::fmt::Result {
}
fn visit_seq<A>(
mut self, mut seq: A,
- ) -> Result<Self::Value, A::Error> where A: #serde::de::SeqAccess<'de> {
- let mut accum = ::enumset::EnumSet::<#name>::new();
+ ) -> #core::result::Result<Self::Value, A::Error> where
+ A: #serde::de::SeqAccess<'de>
+ {
+ let mut accum = #enumset::EnumSet::<#name>::new();
while let #core::prelude::v1::Some(val) = seq.next_element::<#name>()? {
accum |= val;
}
}
}
} else {
+ let serialize_repr = info.serde_repr();
+ let check_unknown = if info.serialize_deny_unknown {
+ quote! {
+ if value & !#all_variants != 0 {
+ use #serde::de::Error;
+ return #core::prelude::v1::Err(
+ D::Error::custom("enumset contains unknown bits")
+ )
+ }
+ }
+ } else {
+ quote! {}
+ };
quote! {
fn serialize<S: #serde::Serializer>(
- set: ::enumset::EnumSet<#name>, ser: S,
+ set: #enumset::EnumSet<#name>, ser: S,
) -> #core::result::Result<S::Ok, S::Error> {
- use #serde::Serialize;
- <#name as ::enumset::EnumSetType>::Repr::serialize(&set.__enumset_underlying, ser)
+ #serde::Serialize::serialize(&(set.__priv_repr as #serialize_repr), ser)
}
fn deserialize<'de, D: #serde::Deserializer<'de>>(
de: D,
- ) -> #core::result::Result<::enumset::EnumSet<#name>, D::Error> {
- use #serde::Deserialize;
- #core::prelude::v1::Ok(::enumset::EnumSet {
- __enumset_underlying: <#name as ::enumset::EnumSetType>::Repr::deserialize(de)?,
+ ) -> #core::result::Result<#enumset::EnumSet<#name>, D::Error> {
+ let value = <#serialize_repr as #serde::Deserialize>::deserialize(de)?;
+ #check_unknown
+ #core::prelude::v1::Ok(#enumset::EnumSet {
+ __priv_repr: (value & #all_variants) as #repr,
})
}
}
};
#[cfg(not(feature = "serde"))]
- let serde_ops = quote! { };
+ let serde_ops = quote! {};
+
+ let is_uninhabited = info.variants.is_empty();
+ let is_zst = info.variants.len() == 1;
+ let into_impl = if is_uninhabited {
+ quote! {
+ fn enum_into_u32(self) -> u32 {
+ panic!(concat!(stringify!(#name), " is uninhabited."))
+ }
+ unsafe fn enum_from_u32(val: u32) -> Self {
+ panic!(concat!(stringify!(#name), " is uninhabited."))
+ }
+ }
+ } else if is_zst {
+ let variant = &info.variants[0].name;
+ quote! {
+ fn enum_into_u32(self) -> u32 {
+ self as u32
+ }
+ unsafe fn enum_from_u32(val: u32) -> Self {
+ #name::#variant
+ }
+ }
+ } else {
+ let variant_name: Vec<_> = info.variants.iter().map(|x| &x.name).collect();
+ let variant_value: Vec<_> = info.variants.iter().map(|x| x.variant_repr).collect();
+
+ let const_field: Vec<_> = ["IS_U8", "IS_U16", "IS_U32", "IS_U64", "IS_U128"]
+ .iter()
+ .map(|x| Ident::new(x, Span::call_site()))
+ .collect();
+ let int_type: Vec<_> = ["u8", "u16", "u32", "u64", "u128"]
+ .iter()
+ .map(|x| Ident::new(x, Span::call_site()))
+ .collect();
+
+ quote! {
+ fn enum_into_u32(self) -> u32 {
+ self as u32
+ }
+ unsafe fn enum_from_u32(val: u32) -> Self {
+ // We put these in const fields so the branches they guard aren't generated even
+ // on -O0
+ #(const #const_field: bool =
+ #core::mem::size_of::<#name>() == #core::mem::size_of::<#int_type>();)*
+ match val {
+ // Every valid variant value has an explicit branch. If they get optimized out,
+ // great. If the representation has changed somehow, and they don't, oh well,
+ // there's still no UB.
+ #(#variant_value => #name::#variant_name,)*
+ // Helps hint to the LLVM that this is a transmute. Note that this branch is
+ // still unreachable.
+ #(x if #const_field => {
+ let x = x as #int_type;
+ *(&x as *const _ as *const #name)
+ })*
+ // Default case. Sometimes causes LLVM to generate a table instead of a simple
+ // transmute, but, oh well.
+ _ => #core::hint::unreachable_unchecked(),
+ }
+ }
+ }
+ };
+
+ let eq_impl = if is_uninhabited {
+ quote!(panic!(concat!(stringify!(#name), " is uninhabited.")))
+ } else {
+ quote!((*self as u32) == (*other as u32))
+ };
+
+ // used in the enum_set! macro `const fn`s.
+ let self_as_repr_mask = if is_uninhabited {
+ quote! { 0 } // impossible anyway
+ } else {
+ quote! { 1 << self as #repr }
+ };
+
+ let super_impls = if info.no_super_impls {
+ quote! {}
+ } else {
+ quote! {
+ impl #core::cmp::PartialEq for #name {
+ fn eq(&self, other: &Self) -> bool {
+ #eq_impl
+ }
+ }
+ impl #core::cmp::Eq for #name { }
+ #[allow(clippy::expl_impl_clone_on_copy)]
+ impl #core::clone::Clone for #name {
+ fn clone(&self) -> Self {
+ *self
+ }
+ }
+ impl #core::marker::Copy for #name { }
+ }
+ };
+
+ let impl_with_repr = if info.explicit_mem_repr.is_some() {
+ quote! {
+ unsafe impl #enumset::EnumSetTypeWithRepr for #name {
+ type Repr = #repr;
+ }
+ }
+ } else {
+ quote! {}
+ };
quote! {
- unsafe impl ::enumset::EnumSetType for #name {
+ unsafe impl #enumset::__internal::EnumSetTypePrivate for #name {
type Repr = #repr;
const ALL_BITS: Self::Repr = #all_variants;
+ #into_impl
+ #serde_ops
+ }
- fn enum_into_u8(self) -> u8 {
- self as u8
- }
- unsafe fn enum_from_u8(val: u8) -> Self {
- #core::mem::transmute(val)
+ unsafe impl #enumset::EnumSetType for #name { }
+
+ #impl_with_repr
+ #super_impls
+
+ impl #name {
+ /// Creates a new enumset with only this variant.
+ #[deprecated(note = "This method is an internal implementation detail generated by \
+ the `enumset` crate's procedural macro. It should not be used \
+ directly. Use `EnumSet::only` instead.")]
+ #[doc(hidden)]
+ pub const fn __impl_enumset_internal__const_only(self) -> #enumset::EnumSet<#name> {
+ #enumset::EnumSet { __priv_repr: #self_as_repr_mask }
}
- #serde_ops
+ /// Creates a new enumset with this variant added.
+ #[deprecated(note = "This method is an internal implementation detail generated by \
+ the `enumset` crate's procedural macro. It should not be used \
+ directly. Use the `|` operator instead.")]
+ #[doc(hidden)]
+ pub const fn __impl_enumset_internal__const_merge(
+ self, chain: #enumset::EnumSet<#name>,
+ ) -> #enumset::EnumSet<#name> {
+ #enumset::EnumSet { __priv_repr: chain.__priv_repr | #self_as_repr_mask }
+ }
}
#ops
- #derives
}
}
-#[proc_macro_derive(EnumSetType,
- attributes(enumset_no_ops, enumset_no_derives, enumset_serialize_as_list))]
+#[proc_macro_derive(EnumSetType, attributes(enumset))]
pub fn derive_enum_set_type(input: TokenStream) -> TokenStream {
let input: DeriveInput = parse_macro_input!(input);
- if let Data::Enum(data) = input.data {
- if !input.generics.params.is_empty() {
- error(input.generics.span(),
- "`#[derive(EnumSetType)]` cannot be used on enums with type parameters.")
- } else {
- let mut all_variants = 0u128;
- let mut max_variant = 0;
- let mut current_variant = 0;
- let mut has_manual_discriminant = false;
-
- for variant in &data.variants {
- if let Fields::Unit = variant.fields {
- if let Some((_, expr)) = &variant.discriminant {
- if let Expr::Lit(ExprLit { lit: Lit::Int(i), .. }) = expr {
- current_variant = i.value();
- has_manual_discriminant = true;
- } else {
- return error(variant.span(), "Unrecognized discriminant for variant.")
- }
- }
-
- if current_variant >= 128 {
- let message = if has_manual_discriminant {
- "`#[derive(EnumSetType)]` only supports enum discriminants up to 127."
- } else {
- "`#[derive(EnumSetType)]` only supports enums up to 128 variants."
- };
- return error(variant.span(), message)
- }
-
- if all_variants & (1 << current_variant) != 0 {
- return error(variant.span(),
- &format!("Duplicate enum discriminant: {}", current_variant))
- }
- all_variants |= 1 << current_variant;
- if current_variant > max_variant {
- max_variant = current_variant
- }
-
- current_variant += 1;
- } else {
- return error(variant.span(),
- "`#[derive(EnumSetType)]` can only be used on C-like enums.")
- }
- }
-
- let repr = Ident::new(if max_variant <= 7 {
- "u8"
- } else if max_variant <= 15 {
- "u16"
- } else if max_variant <= 31 {
- "u32"
- } else if max_variant <= 63 {
- "u64"
- } else if max_variant <= 127 {
- "u128"
- } else {
- panic!("max_variant > 127?")
- }, Span::call_site());
-
- let mut no_ops = false;
- let mut no_derives = false;
- let mut serialize_as_list = false;
-
- for attr in &input.attrs {
- let span = attr.span();
- let Attribute { tts, path: Path { segments, ..}, .. } = attr;
-
- if segments.len() == 1 {
- let name = segments[0].ident.to_string();
- let mut is_attr = false;
- match name.as_str() {
- "enumset_no_ops" => {
- no_ops = true;
- is_attr = true;
- }
- "enumset_no_derives" => {
- no_derives = true;
- is_attr = true;
- }
- "enumset_serialize_as_list" => {
- serialize_as_list = true;
- is_attr = true;
- }
- _ => { }
- }
- if is_attr && !tts.is_empty() {
- return error(span, &format!("`#[{}]` takes no arguments.", name))
- }
- }
+ let attrs: EnumsetAttrs = match EnumsetAttrs::from_derive_input(&input) {
+ Ok(attrs) => attrs,
+ Err(e) => return e.write_errors().into(),
+ };
+ match derive_enum_set_type_0(input, attrs) {
+ Ok(v) => v,
+ Err(e) => e.to_compile_error().into(),
+ }
+}
+fn derive_enum_set_type_0(input: DeriveInput, attrs: EnumsetAttrs) -> Result<TokenStream> {
+ if !input.generics.params.is_empty() {
+ error(
+ input.generics.span(),
+ "`#[derive(EnumSetType)]` cannot be used on enums with type parameters.",
+ )
+ } else if let Data::Enum(data) = &input.data {
+ let mut info = EnumSetInfo::new(&input, attrs);
+ for attr in &input.attrs {
+ if attr.path.is_ident(&Ident::new("repr", Span::call_site())) {
+ let meta: Ident = attr.parse_args()?;
+ info.push_explicit_repr(attr.span(), meta.to_string().as_str())?;
}
-
- enum_set_type_impl(
- &input.ident, all_variants, repr, no_ops, no_derives, serialize_as_list,
- ).into()
}
+ for variant in &data.variants {
+ info.push_variant(variant)?;
+ }
+ info.validate()?;
+ Ok(enum_set_type_impl(info).into())
} else {
error(input.span(), "`#[derive(EnumSetType)]` may only be used on enums")
}
projects / enumset.git / blobdiff