Slight macro cleanup

This commit is contained in:
Dreaded_X 2024-04-26 05:18:46 +02:00
parent 55237a2ba2
commit 20feaa6308
Signed by: Dreaded_X
GPG Key ID: FA5F485356B0D2D4
3 changed files with 332 additions and 314 deletions

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@ -1,11 +1,9 @@
use itertools::Itertools;
use proc_macro2::TokenStream;
use quote::{quote, quote_spanned};
use syn::parse::{Parse, ParseStream};
use syn::punctuated::Punctuated;
use syn::spanned::Spanned;
use syn::token::Paren;
use syn::{parenthesized, parse_macro_input, DeriveInput, Expr, LitStr, Result, Token};
mod lua_device;
mod lua_device_config;
use lua_device::impl_lua_device_macro;
use lua_device_config::impl_lua_device_config_macro;
use syn::{parse_macro_input, DeriveInput};
#[proc_macro_derive(LuaDevice, attributes(config))]
pub fn lua_device_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
@ -14,315 +12,9 @@ pub fn lua_device_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStr
impl_lua_device_macro(&ast).into()
}
fn impl_lua_device_macro(ast: &syn::DeriveInput) -> TokenStream {
let name = &ast.ident;
// TODO: Handle errors properly
// This includes making sure one, and only one config is specified
let config = if let syn::Data::Struct(syn::DataStruct {
fields: syn::Fields::Named(syn::FieldsNamed { ref named, .. }),
..
}) = ast.data
{
named
.iter()
.find(|&field| {
field
.attrs
.iter()
.any(|attr| attr.path().is_ident("config"))
})
.map(|field| field.ty.clone())
.unwrap()
} else {
unimplemented!()
};
let gen = quote! {
impl #name {
pub fn register_with_lua(lua: &mlua::Lua) -> mlua::Result<()> {
lua.globals().set(stringify!(#name), lua.create_proxy::<#name>()?)
}
}
impl mlua::UserData for #name {
fn add_methods<'lua, M: mlua::UserDataMethods<'lua, Self>>(methods: &mut M) {
methods.add_function("new", |lua, config: mlua::Value| {
let config: #config = mlua::FromLua::from_lua(config, lua)?;
let config: Box<dyn crate::device_manager::DeviceConfig> = Box::new(config);
Ok(config)
});
}
}
};
gen
}
mod kw {
syn::custom_keyword!(device_config);
syn::custom_keyword!(flatten);
syn::custom_keyword!(from_lua);
syn::custom_keyword!(rename);
syn::custom_keyword!(with);
syn::custom_keyword!(from);
syn::custom_keyword!(default);
}
#[derive(Debug)]
enum Argument {
Flatten {
_keyword: kw::flatten,
},
FromLua {
_keyword: kw::from_lua,
},
Rename {
_keyword: kw::rename,
_paren: Paren,
ident: LitStr,
},
With {
_keyword: kw::with,
_paren: Paren,
// TODO: Ideally we capture this better
expr: Expr,
},
From {
_keyword: kw::from,
_paren: Paren,
ty: syn::Type,
},
Default {
_keyword: kw::default,
},
DefaultExpr {
_keyword: kw::default,
_paren: Paren,
expr: Expr,
},
}
impl Parse for Argument {
fn parse(input: ParseStream) -> Result<Self> {
let lookahead = input.lookahead1();
if lookahead.peek(kw::flatten) {
Ok(Self::Flatten {
_keyword: input.parse()?,
})
} else if lookahead.peek(kw::from_lua) {
Ok(Self::FromLua {
_keyword: input.parse()?,
})
} else if lookahead.peek(kw::rename) {
let content;
Ok(Self::Rename {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
ident: content.parse()?,
})
} else if lookahead.peek(kw::with) {
let content;
Ok(Self::With {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
expr: content.parse()?,
})
} else if lookahead.peek(kw::from) {
let content;
Ok(Self::From {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
ty: content.parse()?,
})
} else if lookahead.peek(kw::default) {
let keyword = input.parse()?;
if input.peek(Paren) {
let content;
Ok(Self::DefaultExpr {
_keyword: keyword,
_paren: parenthesized!(content in input),
expr: content.parse()?,
})
} else {
Ok(Self::Default { _keyword: keyword })
}
} else {
Err(lookahead.error())
}
}
}
#[derive(Debug)]
struct Args {
args: Punctuated<Argument, Token![,]>,
}
impl Parse for Args {
fn parse(input: ParseStream) -> Result<Self> {
Ok(Self {
args: input.parse_terminated(Argument::parse, Token![,])?,
})
}
}
#[proc_macro_derive(LuaDeviceConfig, attributes(device_config))]
pub fn lua_device_config_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
let ast = parse_macro_input!(input as DeriveInput);
impl_lua_device_config_macro(&ast).into()
}
fn impl_lua_device_config_macro(ast: &syn::DeriveInput) -> TokenStream {
let name = &ast.ident;
let fields = if let syn::Data::Struct(syn::DataStruct {
fields: syn::Fields::Named(syn::FieldsNamed { ref named, .. }),
..
}) = ast.data
{
named
} else {
return quote_spanned! {ast.span() => compile_error!("This macro only works on named structs")};
};
let field_names: Vec<_> = fields
.iter()
.map(|field| field.ident.clone().unwrap())
.collect();
let fields: Vec<_> = fields
.iter()
.map(|field| {
let field_name = field.ident.clone().unwrap();
let (args, errors): (Vec<_>, Vec<_>) = field
.attrs
.iter()
.filter_map(|attr| {
if attr.path().is_ident("device_config") {
Some(attr.parse_args::<Args>().map(|args| args.args))
} else {
None
}
})
.partition_result();
let errors: Vec<_> = errors
.iter()
.map(|error| error.to_compile_error())
.collect();
if !errors.is_empty() {
return quote! { #(#errors)* };
}
let args: Vec<_> = args.into_iter().flatten().collect();
let table_name = match args
.iter()
.filter_map(|arg| match arg {
Argument::Rename { ident, .. } => Some(ident.value()),
_ => None,
})
.collect::<Vec<_>>()
.as_slice()
{
[] => field_name.to_string(),
[rename] => rename.to_owned(),
_ => return quote_spanned! {field.span() => compile_error!("Field contains duplicate 'rename'")},
};
// TODO: Detect Option<_> properly and use Default::default() as fallback automatically
let missing = format!("Missing field '{table_name}'");
let default = match args
.iter()
.filter_map(|arg| match arg {
Argument::Default { .. } => Some(quote! { Default::default() }),
Argument::DefaultExpr { expr, .. } => Some(quote! { (#expr) }),
_ => None,
})
.collect::<Vec<_>>()
.as_slice()
{
[] => quote! {panic!(#missing)},
[default] => default.to_owned(),
_ => return quote_spanned! {field.span() => compile_error!("Field contains duplicate 'default'")},
};
let value = match args
.iter()
.filter_map(|arg| match arg {
Argument::Flatten { .. } => Some(quote! {
mlua::LuaSerdeExt::from_value_with(lua, value.clone(), mlua::DeserializeOptions::new().deny_unsupported_types(false))?
}),
Argument::FromLua { .. } => Some(quote! {
if table.contains_key(#table_name)? {
table.get(#table_name)?
} else {
#default
}
}),
_ => None,
})
.collect::<Vec<_>>()
.as_slice() {
[] => quote! {
{
let #field_name: mlua::Value = table.get(#table_name)?;
if !#field_name.is_nil() {
mlua::LuaSerdeExt::from_value(lua, #field_name)?
} else {
#default
}
}
},
[value] => value.to_owned(),
_ => return quote_spanned! {field.span() => compile_error!("Only one of either 'flatten' or 'from_lua' is allowed")},
};
let value = match args
.iter()
.filter_map(|arg| match arg {
Argument::From { ty, .. } => Some(quote! {
{
let temp: #ty = #value;
temp.into()
}
}),
Argument::With { expr, .. } => Some(quote! {
{
let temp = #value;
(#expr)(temp)
}
}),
_ => None,
})
.collect::<Vec<_>>()
.as_slice() {
[] => value,
[value] => value.to_owned(),
_ => return quote_spanned! {field.span() => compile_error!("Field contains duplicate 'as'")},
};
quote! { #value }
})
.zip(field_names)
.map(|(value, name)| quote! { #name: #value })
.collect();
let gen = quote! {
impl<'lua> mlua::FromLua<'lua> for #name {
fn from_lua(value: mlua::Value<'lua>, lua: &'lua mlua::Lua) -> mlua::Result<Self> {
if !value.is_table() {
panic!("Expected table");
}
let table = value.as_table().unwrap();
Ok(#name {
#(#fields,)*
})
}
}
};
gen
}

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@ -0,0 +1,46 @@
use proc_macro2::TokenStream;
use quote::quote;
use syn::{Data, DataStruct, DeriveInput, Fields, FieldsNamed};
pub fn impl_lua_device_macro(ast: &DeriveInput) -> TokenStream {
let name = &ast.ident;
// TODO: Handle errors properly
// This includes making sure one, and only one config is specified
let config = if let Data::Struct(DataStruct {
fields: Fields::Named(FieldsNamed { ref named, .. }),
..
}) = ast.data
{
named
.iter()
.find(|&field| {
field
.attrs
.iter()
.any(|attr| attr.path().is_ident("config"))
})
.map(|field| field.ty.clone())
.unwrap()
} else {
unimplemented!()
};
let gen = quote! {
impl #name {
pub fn register_with_lua(lua: &mlua::Lua) -> mlua::Result<()> {
lua.globals().set(stringify!(#name), lua.create_proxy::<#name>()?)
}
}
impl mlua::UserData for #name {
fn add_methods<'lua, M: mlua::UserDataMethods<'lua, Self>>(methods: &mut M) {
methods.add_function("new", |lua, config: mlua::Value| {
let config: #config = mlua::FromLua::from_lua(config, lua)?;
let config: Box<dyn crate::device_manager::DeviceConfig> = Box::new(config);
Ok(config)
});
}
}
};
gen
}

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@ -0,0 +1,280 @@
use itertools::Itertools;
use proc_macro2::TokenStream;
use quote::{quote, quote_spanned};
use syn::parse::{Parse, ParseStream};
use syn::punctuated::Punctuated;
use syn::spanned::Spanned;
use syn::token::Paren;
use syn::{
parenthesized, Data, DataStruct, DeriveInput, Expr, Field, Fields, FieldsNamed, LitStr, Result,
Token, Type,
};
mod kw {
use syn::custom_keyword;
custom_keyword!(device_config);
custom_keyword!(flatten);
custom_keyword!(from_lua);
custom_keyword!(rename);
custom_keyword!(with);
custom_keyword!(from);
custom_keyword!(default);
}
#[derive(Debug)]
enum Argument {
Flatten {
_keyword: kw::flatten,
},
FromLua {
_keyword: kw::from_lua,
},
Rename {
_keyword: kw::rename,
_paren: Paren,
ident: LitStr,
},
With {
_keyword: kw::with,
_paren: Paren,
// TODO: Ideally we capture this better
expr: Expr,
},
From {
_keyword: kw::from,
_paren: Paren,
ty: Type,
},
Default {
_keyword: kw::default,
},
DefaultExpr {
_keyword: kw::default,
_paren: Paren,
expr: Expr,
},
}
impl Parse for Argument {
fn parse(input: ParseStream) -> Result<Self> {
let lookahead = input.lookahead1();
if lookahead.peek(kw::flatten) {
Ok(Self::Flatten {
_keyword: input.parse()?,
})
} else if lookahead.peek(kw::from_lua) {
Ok(Self::FromLua {
_keyword: input.parse()?,
})
} else if lookahead.peek(kw::rename) {
let content;
Ok(Self::Rename {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
ident: content.parse()?,
})
} else if lookahead.peek(kw::with) {
let content;
Ok(Self::With {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
expr: content.parse()?,
})
} else if lookahead.peek(kw::from) {
let content;
Ok(Self::From {
_keyword: input.parse()?,
_paren: parenthesized!(content in input),
ty: content.parse()?,
})
} else if lookahead.peek(kw::default) {
let keyword = input.parse()?;
if input.peek(Paren) {
let content;
Ok(Self::DefaultExpr {
_keyword: keyword,
_paren: parenthesized!(content in input),
expr: content.parse()?,
})
} else {
Ok(Self::Default { _keyword: keyword })
}
} else {
Err(lookahead.error())
}
}
}
#[derive(Debug)]
struct Args {
args: Punctuated<Argument, Token![,]>,
}
impl Parse for Args {
fn parse(input: ParseStream) -> Result<Self> {
Ok(Self {
args: input.parse_terminated(Argument::parse, Token![,])?,
})
}
}
fn field_from_lua(field: &Field) -> TokenStream {
let (args, errors): (Vec<_>, Vec<_>) = field
.attrs
.iter()
.filter_map(|attr| {
if attr.path().is_ident("device_config") {
Some(attr.parse_args::<Args>().map(|args| args.args))
} else {
None
}
})
.partition_result();
let errors: Vec<_> = errors
.iter()
.map(|error| error.to_compile_error())
.collect();
if !errors.is_empty() {
return quote! { #(#errors)* };
}
let args: Vec<_> = args.into_iter().flatten().collect();
let table_name = match args
.iter()
.filter_map(|arg| match arg {
Argument::Rename { ident, .. } => Some(ident.value()),
_ => None,
})
.collect::<Vec<_>>()
.as_slice()
{
[] => field.ident.clone().unwrap().to_string(),
[rename] => rename.to_owned(),
_ => {
return quote_spanned! {field.span() => compile_error!("Field contains duplicate 'rename'")}
}
};
// TODO: Detect Option<_> properly and use Default::default() as fallback automatically
let missing = format!("Missing field '{table_name}'");
let default = match args
.iter()
.filter_map(|arg| match arg {
Argument::Default { .. } => Some(quote! { Default::default() }),
Argument::DefaultExpr { expr, .. } => Some(quote! { (#expr) }),
_ => None,
})
.collect::<Vec<_>>()
.as_slice()
{
[] => quote! {panic!(#missing)},
[default] => default.to_owned(),
_ => {
return quote_spanned! {field.span() => compile_error!("Field contains duplicate 'default'")}
}
};
let value = match args
.iter()
.filter_map(|arg| match arg {
Argument::Flatten { .. } => Some(quote! {
mlua::LuaSerdeExt::from_value_with(lua, value.clone(), mlua::DeserializeOptions::new().deny_unsupported_types(false))?
}),
Argument::FromLua { .. } => Some(quote! {
if table.contains_key(#table_name)? {
table.get(#table_name)?
} else {
#default
}
}),
_ => None,
})
.collect::<Vec<_>>()
.as_slice() {
[] => quote! {
{
let value: mlua::Value = table.get(#table_name)?;
if !value.is_nil() {
mlua::LuaSerdeExt::from_value(lua, value)?
} else {
#default
}
}
},
[value] => value.to_owned(),
_ => return quote_spanned! {field.span() => compile_error!("Only one of either 'flatten' or 'from_lua' is allowed")},
};
let value = match args
.iter()
.filter_map(|arg| match arg {
Argument::From { ty, .. } => Some(quote! {
{
let temp: #ty = #value;
temp.into()
}
}),
Argument::With { expr, .. } => Some(quote! {
{
let temp = #value;
(#expr)(temp)
}
}),
_ => None,
})
.collect::<Vec<_>>()
.as_slice()
{
[] => value,
[value] => value.to_owned(),
_ => {
return quote_spanned! {field.span() => compile_error!("Only one of either 'from' or 'with' is allowed")}
}
};
quote! { #value }
}
pub fn impl_lua_device_config_macro(ast: &DeriveInput) -> TokenStream {
let name = &ast.ident;
let fields = if let Data::Struct(DataStruct {
fields: Fields::Named(FieldsNamed { ref named, .. }),
..
}) = ast.data
{
named
} else {
return quote_spanned! {ast.span() => compile_error!("This macro only works on named structs")};
};
let lua_fields: Vec<_> = fields
.iter()
.map(|field| {
let name = field.ident.clone().unwrap();
let value = field_from_lua(field);
quote! { #name: #value }
})
.collect();
let impl_from_lua = quote! {
impl<'lua> mlua::FromLua<'lua> for #name {
fn from_lua(value: mlua::Value<'lua>, lua: &'lua mlua::Lua) -> mlua::Result<Self> {
if !value.is_table() {
panic!("Expected table");
}
let table = value.as_table().unwrap();
Ok(#name {
#(#lua_fields,)*
})
}
}
};
impl_from_lua
}