blob: bc4e90a4871a62b6cc597db9b89d36eb757a71aa [file] [log] [blame]
use crate::attr::{self, Attrs};
use syn::{
Data, DataEnum, DataStruct, DeriveInput, Error, Fields, Generics, Ident, Index, Member, Result,
Type,
};
pub enum Input<'a> {
Struct(Struct<'a>),
Enum(Enum<'a>),
}
pub struct Struct<'a> {
pub attrs: Attrs<'a>,
pub ident: Ident,
pub generics: &'a Generics,
pub fields: Vec<Field<'a>>,
}
pub struct Enum<'a> {
pub attrs: Attrs<'a>,
pub ident: Ident,
pub generics: &'a Generics,
pub variants: Vec<Variant<'a>>,
}
pub struct Variant<'a> {
pub original: &'a syn::Variant,
pub attrs: Attrs<'a>,
pub ident: Ident,
pub fields: Vec<Field<'a>>,
}
pub struct Field<'a> {
pub original: &'a syn::Field,
pub attrs: Attrs<'a>,
pub member: Member,
pub ty: &'a Type,
}
impl<'a> Input<'a> {
pub fn from_syn(node: &'a DeriveInput) -> Result<Self> {
match &node.data {
Data::Struct(data) => Struct::from_syn(node, data).map(Input::Struct),
Data::Enum(data) => Enum::from_syn(node, data).map(Input::Enum),
Data::Union(_) => Err(Error::new_spanned(
node,
"union as errors are not supported",
)),
}
}
}
impl<'a> Struct<'a> {
fn from_syn(node: &'a DeriveInput, data: &'a DataStruct) -> Result<Self> {
Ok(Struct {
attrs: attr::get(&node.attrs)?,
ident: node.ident.clone(),
generics: &node.generics,
fields: Field::multiple_from_syn(&data.fields)?,
})
}
}
impl<'a> Enum<'a> {
fn from_syn(node: &'a DeriveInput, data: &'a DataEnum) -> Result<Self> {
let attrs = attr::get(&node.attrs)?;
let variants = data
.variants
.iter()
.map(|node| {
let mut variant = Variant::from_syn(node)?;
if let display @ None = &mut variant.attrs.display {
*display = attrs.display.clone();
}
Ok(variant)
})
.collect::<Result<_>>()?;
Ok(Enum {
attrs,
ident: node.ident.clone(),
generics: &node.generics,
variants,
})
}
}
impl<'a> Variant<'a> {
fn from_syn(node: &'a syn::Variant) -> Result<Self> {
Ok(Variant {
original: node,
attrs: attr::get(&node.attrs)?,
ident: node.ident.clone(),
fields: Field::multiple_from_syn(&node.fields)?,
})
}
}
impl<'a> Field<'a> {
fn multiple_from_syn(fields: &'a Fields) -> Result<Vec<Self>> {
fields
.iter()
.enumerate()
.map(|(i, field)| Field::from_syn(i, field))
.collect()
}
fn from_syn(i: usize, node: &'a syn::Field) -> Result<Self> {
Ok(Field {
original: node,
attrs: attr::get(&node.attrs)?,
member: node
.ident
.clone()
.map(Member::Named)
.unwrap_or_else(|| Member::Unnamed(Index::from(i))),
ty: &node.ty,
})
}
}