blob: 698a175c0f4e093302769d85ff4b60d8df3f673b [file] [log] [blame]
// Copyright 2017 Serde Developers
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use syn;
use attr;
use check;
use Ctxt;
pub struct Container<'a> {
pub ident: syn::Ident,
pub attrs: attr::Container,
pub body: Body<'a>,
pub generics: &'a syn::Generics,
}
pub enum Body<'a> {
Enum(Vec<Variant<'a>>),
Struct(Style, Vec<Field<'a>>),
}
pub struct Variant<'a> {
pub ident: syn::Ident,
pub attrs: attr::Variant,
pub style: Style,
pub fields: Vec<Field<'a>>,
}
pub struct Field<'a> {
pub ident: Option<syn::Ident>,
pub attrs: attr::Field,
pub ty: &'a syn::Ty,
}
#[derive(Copy, Clone)]
pub enum Style {
Struct,
Tuple,
Newtype,
Unit,
}
impl<'a> Container<'a> {
pub fn from_ast(cx: &Ctxt, item: &'a syn::DeriveInput) -> Container<'a> {
let attrs = attr::Container::from_ast(cx, item);
let mut body = match item.body {
syn::Body::Enum(ref variants) => {
Body::Enum(enum_from_ast(cx, variants, &attrs.default()))
}
syn::Body::Struct(ref variant_data) => {
let (style, fields) = struct_from_ast(cx, variant_data, None, &attrs.default());
Body::Struct(style, fields)
}
};
match body {
Body::Enum(ref mut variants) => for ref mut variant in variants {
variant.attrs.rename_by_rule(attrs.rename_all());
for ref mut field in &mut variant.fields {
field.attrs.rename_by_rule(variant.attrs.rename_all());
}
},
Body::Struct(_, ref mut fields) => for field in fields {
field.attrs.rename_by_rule(attrs.rename_all());
},
}
let item = Container {
ident: item.ident.clone(),
attrs: attrs,
body: body,
generics: &item.generics,
};
check::check(cx, &item);
item
}
}
impl<'a> Body<'a> {
pub fn all_fields(&'a self) -> Box<Iterator<Item = &'a Field<'a>> + 'a> {
match *self {
Body::Enum(ref variants) => {
Box::new(variants.iter().flat_map(|variant| variant.fields.iter()))
}
Body::Struct(_, ref fields) => Box::new(fields.iter()),
}
}
pub fn has_getter(&self) -> bool {
self.all_fields().any(|f| f.attrs.getter().is_some())
}
}
fn enum_from_ast<'a>(
cx: &Ctxt,
variants: &'a [syn::Variant],
container_default: &attr::Default,
) -> Vec<Variant<'a>> {
variants
.iter()
.map(|variant| {
let attrs = attr::Variant::from_ast(cx, variant);
let (style, fields) =
struct_from_ast(cx, &variant.data, Some(&attrs), container_default);
Variant {
ident: variant.ident.clone(),
attrs: attrs,
style: style,
fields: fields,
}
})
.collect()
}
fn struct_from_ast<'a>(
cx: &Ctxt,
data: &'a syn::VariantData,
attrs: Option<&attr::Variant>,
container_default: &attr::Default,
) -> (Style, Vec<Field<'a>>) {
match *data {
syn::VariantData::Struct(ref fields) => (
Style::Struct,
fields_from_ast(cx, fields, attrs, container_default),
),
syn::VariantData::Tuple(ref fields) if fields.len() == 1 => (
Style::Newtype,
fields_from_ast(cx, fields, attrs, container_default),
),
syn::VariantData::Tuple(ref fields) => (
Style::Tuple,
fields_from_ast(cx, fields, attrs, container_default),
),
syn::VariantData::Unit => (Style::Unit, Vec::new()),
}
}
fn fields_from_ast<'a>(
cx: &Ctxt,
fields: &'a [syn::Field],
attrs: Option<&attr::Variant>,
container_default: &attr::Default,
) -> Vec<Field<'a>> {
fields
.iter()
.enumerate()
.map(|(i, field)| Field {
ident: field.ident.clone(),
attrs: attr::Field::from_ast(cx, i, field, attrs, container_default),
ty: &field.ty,
})
.collect()
}