bincode-orig/derive/src/derive_struct.rs

98 lines
3.7 KiB
Rust

use crate::generate::Generator;
use crate::parse::Fields;
use crate::prelude::Delimiter;
use crate::Result;
pub struct DeriveStruct {
pub fields: Fields,
}
impl DeriveStruct {
pub fn generate_encode(self, generator: &mut Generator) -> Result<()> {
let DeriveStruct { fields } = self;
let mut impl_for = generator.impl_for("bincode::enc::Encode");
impl_for
.generate_fn("encode")
.with_generic("E", ["bincode::enc::Encoder"])
.with_self_arg(crate::generate::FnSelfArg::RefSelf)
.with_arg("mut encoder", "E")
.with_return_type("Result<(), bincode::error::EncodeError>")
.body(|fn_body| {
for field in fields.names() {
fn_body.push_parsed(format!(
"bincode::enc::Encode::encode(&self.{}, &mut encoder)?;",
field.to_string()
));
}
fn_body.push_parsed("Ok(())");
});
Ok(())
}
pub fn generate_decode(self, generator: &mut Generator) -> Result<()> {
let DeriveStruct { fields } = self;
if generator.has_lifetimes() {
// struct has a lifetime, implement BorrowDecode
generator
.impl_for_with_de_lifetime("bincode::de::BorrowDecode<'__de>")
.generate_fn("borrow_decode")
.with_generic("D", ["bincode::de::BorrowDecoder<'__de>"])
.with_arg("mut decoder", "D")
.with_return_type("Result<Self, bincode::error::DecodeError>")
.body(|fn_body| {
// Ok(Self {
fn_body.ident_str("Ok");
fn_body.group(Delimiter::Parenthesis, |ok_group| {
ok_group.ident_str("Self");
ok_group.group(Delimiter::Brace, |struct_body| {
for field in fields.names() {
struct_body.push_parsed(format!(
"{}: bincode::de::BorrowDecode::borrow_decode(&mut decoder)?,",
field.to_string()
));
}
});
});
});
Ok(())
} else {
// struct has no lifetimes, implement Decode
let mut impl_for = generator.impl_for("bincode::de::Decode");
impl_for
.generate_fn("decode")
.with_generic("D", ["bincode::de::Decoder"])
.with_arg("mut decoder", "D")
.with_return_type("Result<Self, bincode::error::DecodeError>")
.body(|fn_body| {
// Ok(Self {
fn_body.ident_str("Ok");
fn_body.group(Delimiter::Parenthesis, |ok_group| {
ok_group.ident_str("Self");
ok_group.group(Delimiter::Brace, |struct_body| {
// Fields
// {
// a: bincode::de::Decode::decode(&mut decoder)?,
// b: bincode::de::Decode::decode(&mut decoder)?,
// ...
// }
for field in fields.names() {
struct_body.push_parsed(format!(
"{}: bincode::de::Decode::decode(&mut decoder)?,",
field.to_string()
));
}
});
});
});
Ok(())
}
}
}