rhai/codegen/src/rhai_module.rs
2021-02-18 17:42:49 +08:00

303 lines
11 KiB
Rust

use std::collections::HashMap;
use quote::{quote, ToTokens};
use crate::attrs::ExportScope;
use crate::function::{
flatten_type_groups, print_type, ExportedFn, FnNamespaceAccess, FnSpecialAccess, FN_GET,
FN_IDX_GET, FN_IDX_SET, FN_SET,
};
use crate::module::Module;
pub(crate) type ExportedConst = (String, Box<syn::Type>, syn::Expr);
pub(crate) fn generate_body(
fns: &mut [ExportedFn],
consts: &[ExportedConst],
sub_modules: &mut [Module],
parent_scope: &ExportScope,
) -> proc_macro2::TokenStream {
let mut set_fn_statements: Vec<syn::Stmt> = Vec::new();
let mut set_const_statements: 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_statements.push(
syn::parse2::<syn::Stmt>(quote! {
m.set_var(#const_literal, #const_ref);
})
.unwrap(),
);
}
for item_mod in sub_modules {
item_mod.update_scope(&parent_scope);
if item_mod.skipped() {
continue;
}
let module_name = item_mod.module_name();
let exported_name: syn::LitStr = syn::LitStr::new(
item_mod.exported_name().as_ref(),
proc_macro2::Span::call_site(),
);
let cfg_attrs: Vec<&syn::Attribute> = item_mod
.attrs()
.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 re-parsing 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_names: Vec<String> = function
.arg_list()
.map(|fn_arg| match fn_arg {
syn::FnArg::Receiver(_) => panic!("internal error: receiver fn outside impl!?"),
syn::FnArg::Typed(syn::PatType { pat, ty, .. }) => {
format!("{}: {}", pat.to_token_stream(), print_type(ty))
}
})
.collect();
let fn_input_types: Vec<syn::Expr> = function
.arg_list()
.map(|fn_arg| match fn_arg {
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();
let return_type = function
.return_type()
.map(print_type)
.unwrap_or_else(|| "()".to_string());
for fn_literal in reg_names {
let mut namespace = FnNamespaceAccess::Internal;
match function.params().special {
FnSpecialAccess::None => {}
FnSpecialAccess::Index(_) | FnSpecialAccess::Property(_) => {
let reg_name = fn_literal.value();
if reg_name.starts_with(FN_GET)
|| reg_name.starts_with(FN_SET)
|| reg_name == FN_IDX_GET
|| reg_name == FN_IDX_SET
{
namespace = FnNamespaceAccess::Global;
}
}
}
match function.params().namespace {
FnNamespaceAccess::Unset => (),
ns => namespace = ns,
}
let ns_str = syn::Ident::new(
match namespace {
FnNamespaceAccess::Unset => unreachable!(),
FnNamespaceAccess::Global => "Global",
FnNamespaceAccess::Internal => "Internal",
},
fn_literal.span(),
);
set_fn_statements.push(
syn::parse2::<syn::Stmt>(quote! {
m.set_fn(#fn_literal, FnNamespace::#ns_str, FnAccess::Public,
Some(&[#(#fn_input_names,)* #return_type]), &[#(#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_names(&fn_token_name.to_string()));
gen_fn_tokens.push(function.generate_input_types(&fn_token_name.to_string()));
gen_fn_tokens.push(function.generate_return_type(&fn_token_name.to_string()));
}
let mut generate_fn_call = 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.build_index();
m
}
#[allow(unused_mut)]
pub fn rhai_generate_into_module(m: &mut Module, flatten: bool) {
#(#set_fn_statements)*
#(#set_const_statements)*
if flatten {
#(#set_flattened_mod_blocks)*
} else {
#(#add_mod_blocks)*
}
}
}
})
.unwrap();
let (_, generate_call_content) = generate_fn_call.content.take().unwrap();
quote! {
#(#generate_call_content)*
#(#gen_fn_tokens)*
}
}
pub(crate) fn check_rename_collisions(fns: &Vec<ExportedFn>) -> Result<(), syn::Error> {
fn make_key(name: impl ToString, item_fn: &ExportedFn) -> String {
item_fn
.arg_list()
.fold(name.to_string(), |mut arg_str, fn_arg| {
let type_string: String = match fn_arg {
syn::FnArg::Receiver(_) => unimplemented!("receiver rhai_fns not implemented"),
syn::FnArg::Typed(syn::PatType { ref ty, .. }) => print_type(ty),
};
arg_str.push('.');
arg_str.push_str(&type_string);
arg_str
})
}
let mut renames = HashMap::<String, proc_macro2::Span>::new();
let mut fn_defs = HashMap::<String, proc_macro2::Span>::new();
for item_fn in fns.iter() {
if !item_fn.params().name.is_empty() || item_fn.params().special != FnSpecialAccess::None {
let mut names: Vec<_> = item_fn
.params()
.name
.iter()
.map(|n| (n.clone(), n.clone()))
.collect();
if let Some((s, n, _)) = item_fn.params().special.get_fn_name() {
names.push((s, n));
}
for (name, fn_name) in names {
let current_span = item_fn.params().span.unwrap();
let key = make_key(&name, item_fn);
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 = item_fn.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, item_fn);
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(())
}