| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License.. |
| |
| use syn; |
| use crate::Ctxt; |
| |
| #[derive(Debug)] |
| pub struct Container<'a> { |
| pub ident: syn::Ident, |
| pub body: Body<'a>, |
| pub generics: &'a syn::Generics, |
| } |
| |
| #[derive(Debug)] |
| pub enum Body<'a> { |
| Enum(Vec<Variant<'a>>), |
| Struct(Style, Vec<Field<'a>>), |
| } |
| |
| #[derive(Debug)] |
| pub struct Variant<'a> { |
| pub ident: syn::Ident, |
| pub style: Style, |
| pub fields: Vec<Field<'a>>, |
| } |
| |
| #[derive(Debug)] |
| pub struct Field<'a> { |
| pub ident: Option<syn::Ident>, |
| pub ty: &'a syn::Ty, |
| } |
| |
| #[derive(Copy, Clone, Debug)] |
| pub enum Style { |
| Struct, |
| Tuple, |
| Newtype, |
| Unit, |
| } |
| |
| impl<'a> Container<'a> { |
| pub fn from_ast(_cx: &Ctxt, item: &'a syn::DeriveInput) -> Container<'a> { |
| let body = match item.body { |
| syn::Body::Enum(ref variants) => Body::Enum(enum_from_ast(variants)), |
| syn::Body::Struct(ref variant_data) => { |
| let (style, fields) = struct_from_ast(variant_data); |
| Body::Struct(style, fields) |
| } |
| }; |
| |
| let item = Container { |
| ident: item.ident.clone(), |
| body: body, |
| generics: &item.generics, |
| }; |
| item |
| } |
| } |
| |
| fn enum_from_ast<'a>(variants: &'a [syn::Variant]) -> Vec<Variant<'a>> { |
| variants |
| .iter() |
| .map( |
| |variant| { |
| let (style, fields) = struct_from_ast(&variant.data); |
| Variant { |
| ident: variant.ident.clone(), |
| style: style, |
| fields: fields, |
| } |
| } |
| ) |
| .collect() |
| } |
| |
| fn struct_from_ast<'a>( data: &'a syn::VariantData) -> (Style, Vec<Field<'a>>) { |
| match *data { |
| syn::VariantData::Struct(ref fields) => (Style::Struct, fields_from_ast(fields)), |
| syn::VariantData::Tuple(ref fields) if fields.len() == 1 => { |
| (Style::Newtype, fields_from_ast(fields)) |
| } |
| syn::VariantData::Tuple(ref fields) => (Style::Tuple, fields_from_ast( fields)), |
| syn::VariantData::Unit => (Style::Unit, Vec::new()), |
| } |
| } |
| |
| fn fields_from_ast<'a>(fields: &'a [syn::Field]) -> Vec<Field<'a>> { |
| fields |
| .iter() |
| .map( |
| |field| { |
| Field { |
| ident: field.ident.clone(), |
| ty: &field.ty, |
| } |
| }, |
| ) |
| .collect() |
| } |