rhai/codegen/src/rhai_module.rs
2020-09-29 13:06:48 +08:00

263 lines
9.8 KiB
Rust

use std::collections::HashMap;
use quote::{quote, ToTokens};
use crate::attrs::ExportScope;
use crate::function::{ExportedFn, FnSpecialAccess};
use crate::module::Module;
pub(crate) type ExportedConst = (String, Box<syn::Type>, syn::Expr);
pub(crate) fn generate_body(
fns: &mut [ExportedFn],
consts: &[ExportedConst],
submodules: &mut [Module],
parent_scope: &ExportScope,
) -> proc_macro2::TokenStream {
let mut set_fn_stmts: Vec<syn::Stmt> = Vec::new();
let mut set_const_stmts: Vec<syn::Stmt> = Vec::new();
let mut add_mod_blocks: Vec<syn::ExprBlock> = Vec::new();
let mut set_flattened_mod_blocks: Vec<syn::ExprBlock> = Vec::new();
let str_type_path = syn::parse2::<syn::Path>(quote! { str }).unwrap();
let string_type_path = syn::parse2::<syn::Path>(quote! { String }).unwrap();
for (const_name, _, _) in consts {
let const_literal = syn::LitStr::new(&const_name, proc_macro2::Span::call_site());
let const_ref = syn::Ident::new(&const_name, proc_macro2::Span::call_site());
set_const_stmts.push(
syn::parse2::<syn::Stmt>(quote! {
m.set_var(#const_literal, #const_ref);
})
.unwrap(),
);
}
for itemmod in submodules {
itemmod.update_scope(&parent_scope);
if itemmod.skipped() {
continue;
}
let module_name: &syn::Ident = itemmod.module_name().unwrap();
let exported_name: syn::LitStr = if let Some(name) = itemmod.exported_name() {
syn::LitStr::new(&name, proc_macro2::Span::call_site())
} else {
syn::LitStr::new(&module_name.to_string(), proc_macro2::Span::call_site())
};
let cfg_attrs: Vec<&syn::Attribute> = itemmod
.attrs()
.unwrap()
.iter()
.filter(|&a| a.path.get_ident().map(|i| *i == "cfg").unwrap_or(false))
.collect();
add_mod_blocks.push(
syn::parse2::<syn::ExprBlock>(quote! {
#(#cfg_attrs)* {
m.set_sub_module(#exported_name, self::#module_name::rhai_module_generate());
}
})
.unwrap(),
);
set_flattened_mod_blocks.push(
syn::parse2::<syn::ExprBlock>(quote! {
#(#cfg_attrs)* {
self::#module_name::rhai_generate_into_module(m, flatten);
}
})
.unwrap(),
);
}
// NB: these are token streams, because reparsing messes up "> >" vs ">>"
let mut gen_fn_tokens: Vec<proc_macro2::TokenStream> = Vec::new();
for function in fns {
function.update_scope(&parent_scope);
if function.skipped() {
continue;
}
let fn_token_name = syn::Ident::new(
&format!("{}_token", function.name().to_string()),
function.name().span(),
);
let reg_names = function.exported_names();
let fn_input_types: Vec<syn::Expr> = function
.arg_list()
.map(|fnarg| match fnarg {
syn::FnArg::Receiver(_) => panic!("internal error: receiver fn outside impl!?"),
syn::FnArg::Typed(syn::PatType { ref ty, .. }) => {
let arg_type = match flatten_type_groups(ty.as_ref()) {
syn::Type::Reference(syn::TypeReference {
mutability: None,
ref elem,
..
}) => match flatten_type_groups(elem.as_ref()) {
syn::Type::Path(ref p) if p.path == str_type_path => {
syn::parse2::<syn::Type>(quote! {
ImmutableString })
.unwrap()
}
_ => panic!("internal error: non-string shared reference!?"),
},
syn::Type::Path(ref p) if p.path == string_type_path => {
syn::parse2::<syn::Type>(quote! {
ImmutableString })
.unwrap()
}
syn::Type::Reference(syn::TypeReference {
mutability: Some(_),
ref elem,
..
}) => match flatten_type_groups(elem.as_ref()) {
syn::Type::Path(ref p) => syn::parse2::<syn::Type>(quote! {
#p })
.unwrap(),
_ => panic!("internal error: invalid mutable reference!?"),
},
t => t.clone(),
};
syn::parse2::<syn::Expr>(quote! {
core::any::TypeId::of::<#arg_type>()})
.unwrap()
}
})
.collect();
for fn_literal in reg_names {
set_fn_stmts.push(
syn::parse2::<syn::Stmt>(quote! {
m.set_fn(#fn_literal, FnAccess::Public, &[#(#fn_input_types),*],
#fn_token_name().into());
})
.unwrap(),
);
}
gen_fn_tokens.push(quote! {
#[allow(non_camel_case_types)]
struct #fn_token_name();
});
gen_fn_tokens.push(function.generate_impl(&fn_token_name.to_string()));
gen_fn_tokens.push(function.generate_callable(&fn_token_name.to_string()));
gen_fn_tokens.push(function.generate_input_types(&fn_token_name.to_string()));
}
let mut generate_fncall = syn::parse2::<syn::ItemMod>(quote! {
pub mod generate_info {
#[allow(unused_imports)]
use super::*;
pub fn rhai_module_generate() -> Module {
let mut m = Module::new();
rhai_generate_into_module(&mut m, false);
m
}
#[allow(unused_mut)]
pub fn rhai_generate_into_module(m: &mut Module, flatten: bool) {
#(#set_fn_stmts)*
#(#set_const_stmts)*
if flatten {
#(#set_flattened_mod_blocks)*
} else {
#(#add_mod_blocks)*
}
}
}
})
.unwrap();
let (_, generate_call_content) = generate_fncall.content.take().unwrap();
quote! {
#(#generate_call_content)*
#(#gen_fn_tokens)*
}
}
pub(crate) fn flatten_type_groups(ty: &syn::Type) -> &syn::Type {
match ty {
syn::Type::Group(syn::TypeGroup { ref elem, .. })
| syn::Type::Paren(syn::TypeParen { ref elem, .. }) => flatten_type_groups(elem.as_ref()),
_ => ty,
}
}
pub(crate) fn check_rename_collisions(fns: &Vec<ExportedFn>) -> Result<(), syn::Error> {
fn make_key(name: impl ToString, itemfn: &ExportedFn) -> String {
itemfn
.arg_list()
.fold(name.to_string(), |mut argstr, fnarg| {
let type_string: String = match fnarg {
syn::FnArg::Receiver(_) => unimplemented!("receiver rhai_fns not implemented"),
syn::FnArg::Typed(syn::PatType { ref ty, .. }) => {
ty.as_ref().to_token_stream().to_string()
}
};
argstr.push('.');
argstr.push_str(&type_string);
argstr
})
}
let mut renames = HashMap::<String, proc_macro2::Span>::new();
let mut fn_defs = HashMap::<String, proc_macro2::Span>::new();
for itemfn in fns.iter() {
if itemfn.params().name.is_some() || itemfn.params().special != FnSpecialAccess::None {
let mut names = itemfn
.params()
.name
.as_ref()
.map(|v| v.iter().map(|n| (n.clone(), n.clone())).collect())
.unwrap_or_else(|| Vec::new());
if let Some((s, n, _)) = itemfn.params().special.get_fn_name() {
names.push((s, n));
}
for (name, fn_name) in names {
let current_span = itemfn.params().span.as_ref().unwrap();
let key = make_key(&name, itemfn);
if let Some(other_span) = renames.insert(key, *current_span) {
let mut err = syn::Error::new(
*current_span,
format!("duplicate Rhai signature for '{}'", &fn_name),
);
err.combine(syn::Error::new(
other_span,
format!("duplicated function renamed '{}'", &fn_name),
));
return Err(err);
}
}
} else {
let ident = itemfn.name();
if let Some(other_span) = fn_defs.insert(ident.to_string(), ident.span()) {
let mut err = syn::Error::new(
ident.span(),
format!("duplicate function '{}'", ident.to_string()),
);
err.combine(syn::Error::new(
other_span,
format!("duplicated function '{}'", ident.to_string()),
));
return Err(err);
}
let key = make_key(ident, itemfn);
if let Some(fn_span) = renames.get(&key) {
let mut err = syn::Error::new(
ident.span(),
format!("duplicate Rhai signature for '{}'", &ident),
);
err.combine(syn::Error::new(
*fn_span,
format!("duplicated function '{}'", &ident),
));
return Err(err);
}
}
}
Ok(())
}