use syntax::ast;
use syntax::codemap::{DUMMY_SP, Span, respan};
use attr::AttrBuilder;
use ident::ToIdent;
use invoke::{Invoke, Identity};
use struct_field::StructFieldBuilder;
use variant_data::{
VariantDataBuilder,
VariantDataStructBuilder,
VariantDataTupleBuilder,
};
pub struct VariantBuilder<F=Identity> {
callback: F,
span: Span,
attrs: Vec<ast::Attribute>,
id: ast::Ident,
}
impl VariantBuilder {
pub fn new<T>(id: T) -> Self
where T: ToIdent,
{
VariantBuilder::with_callback(id, Identity)
}
}
impl<F> VariantBuilder<F>
where F: Invoke<ast::Variant>,
{
pub fn with_callback<T>(id: T, callback: F) -> Self
where T: ToIdent,
{
VariantBuilder {
callback: callback,
span: DUMMY_SP,
attrs: vec![],
id: id.to_ident(),
}
}
pub fn span(mut self, span: Span) -> Self {
self.span = span;
self
}
pub fn attr(self) -> AttrBuilder<Self> {
let span = self.span;
AttrBuilder::with_callback(self).span(span)
}
pub fn unit(self) -> F::Result {
VariantDataBuilder::with_callback(self).unit()
}
pub fn tuple(self) -> StructFieldBuilder<VariantDataTupleBuilder<Self>> {
VariantDataBuilder::with_callback(self).tuple()
}
pub fn struct_(self) -> VariantDataStructBuilder<Self> {
VariantDataBuilder::with_callback(self).struct_()
}
pub fn build_variant_data(self, data: ast::VariantData) -> F::Result {
let variant_ = ast::Variant_ {
name: self.id,
attrs: self.attrs,
data: data,
disr_expr: None,
};
let variant = respan(self.span, variant_);
self.callback.invoke(variant)
}
pub fn build_variant_(self, variant: ast::Variant_) -> F::Result {
let variant = respan(self.span, variant);
self.build(variant)
}
pub fn build(self, variant: ast::Variant) -> F::Result {
self.callback.invoke(variant)
}
}
impl<F> Invoke<ast::Attribute> for VariantBuilder<F>
where F: Invoke<ast::Variant>,
{
type Result = Self;
fn invoke(mut self, attr: ast::Attribute) -> Self {
self.attrs.push(attr);
self
}
}
impl<F> Invoke<ast::VariantData> for VariantBuilder<F>
where F: Invoke<ast::Variant>,
{
type Result = F::Result;
fn invoke(self, data: ast::VariantData) -> F::Result {
self.build_variant_data(data)
}
}