882 lines
31 KiB
Rust
882 lines
31 KiB
Rust
use proc_macro2::{Span, TokenStream};
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use quote::{quote, quote_spanned, ToTokens};
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use syn::{
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parse::{Parse, ParseStream},
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spanned::Spanned,
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};
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#[cfg(no_std)]
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use alloc::format;
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#[cfg(not(no_std))]
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use std::format;
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use std::borrow::Cow;
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use crate::attrs::{ExportInfo, ExportScope, ExportedParams};
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#[derive(Clone, Debug, Eq, PartialEq, Copy, Hash)]
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pub enum FnNamespaceAccess {
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Unset,
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Global,
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Internal,
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}
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impl Default for FnNamespaceAccess {
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fn default() -> Self {
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Self::Unset
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}
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}
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#[derive(Clone, Debug, Eq, PartialEq, Copy, Hash)]
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pub enum Index {
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Get,
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Set,
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}
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#[derive(Clone, Debug, Eq, PartialEq, Hash)]
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pub enum Property {
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Get(syn::Ident),
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Set(syn::Ident),
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}
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#[derive(Clone, Debug, Eq, PartialEq, Hash)]
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pub enum FnSpecialAccess {
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None,
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Index(Index),
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Property(Property),
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}
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impl Default for FnSpecialAccess {
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fn default() -> FnSpecialAccess {
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FnSpecialAccess::None
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}
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}
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impl FnSpecialAccess {
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pub fn get_fn_name(&self) -> Option<(String, String, Span)> {
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match self {
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FnSpecialAccess::None => None,
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FnSpecialAccess::Property(Property::Get(ref g)) => {
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Some((format!("{}{}", FN_GET, g), g.to_string(), g.span()))
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}
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FnSpecialAccess::Property(Property::Set(ref s)) => {
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Some((format!("{}{}", FN_SET, s), s.to_string(), s.span()))
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}
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FnSpecialAccess::Index(Index::Get) => Some((
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FN_IDX_GET.to_string(),
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"index_get".to_string(),
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Span::call_site(),
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)),
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FnSpecialAccess::Index(Index::Set) => Some((
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FN_IDX_SET.to_string(),
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"index_set".to_string(),
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Span::call_site(),
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)),
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}
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}
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}
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pub fn flatten_type_groups(ty: &syn::Type) -> &syn::Type {
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match ty {
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syn::Type::Group(syn::TypeGroup { ref elem, .. })
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| syn::Type::Paren(syn::TypeParen { ref elem, .. }) => flatten_type_groups(elem.as_ref()),
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_ => ty,
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}
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}
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pub fn print_type(ty: &syn::Type) -> String {
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ty.to_token_stream()
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.to_string()
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.replace(" , ", ", ")
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.replace("& ", "&")
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.replace(" :: ", "::")
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.replace(" ( ", "(")
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.replace(" ) ", ")")
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.replace(" < ", "<")
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.replace(" > ", ">")
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}
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#[derive(Debug, Default)]
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pub struct ExportedFnParams {
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pub name: Vec<String>,
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pub return_raw: Option<Span>,
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pub pure: Option<Span>,
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pub skip: bool,
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pub special: FnSpecialAccess,
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pub namespace: FnNamespaceAccess,
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pub span: Option<Span>,
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}
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pub const FN_GET: &str = "get$";
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pub const FN_SET: &str = "set$";
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pub const FN_IDX_GET: &str = "index$get$";
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pub const FN_IDX_SET: &str = "index$set$";
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impl Parse for ExportedFnParams {
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fn parse(args: ParseStream) -> syn::Result<Self> {
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if args.is_empty() {
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return Ok(ExportedFnParams::default());
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}
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let info = crate::attrs::parse_attr_items(args)?;
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Self::from_info(info)
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}
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}
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impl ExportedParams for ExportedFnParams {
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fn parse_stream(args: ParseStream) -> syn::Result<Self> {
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Self::parse(args)
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}
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fn no_attrs() -> Self {
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Default::default()
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}
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fn from_info(info: crate::attrs::ExportInfo) -> syn::Result<Self> {
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let ExportInfo {
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item_span: span,
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items: attrs,
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} = info;
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let mut name = Vec::new();
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let mut return_raw = None;
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let mut pure = None;
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let mut skip = false;
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let mut namespace = FnNamespaceAccess::Unset;
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let mut special = FnSpecialAccess::None;
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for attr in attrs {
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let crate::attrs::AttrItem {
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key,
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value,
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span: item_span,
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} = attr;
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match (key.to_string().as_ref(), value) {
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("get", None) | ("set", None) | ("name", None) => {
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return Err(syn::Error::new(key.span(), "requires value"))
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}
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("name", Some(s)) if s.value() == FN_IDX_GET => {
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return Err(syn::Error::new(
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item_span,
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"use attribute 'index_get' instead",
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))
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}
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("name", Some(s)) if s.value() == FN_IDX_SET => {
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return Err(syn::Error::new(
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item_span,
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"use attribute 'index_set' instead",
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))
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}
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("name", Some(s)) if s.value().starts_with(FN_GET) => {
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return Err(syn::Error::new(
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item_span,
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format!(
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"use attribute 'getter = \"{}\"' instead",
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&s.value()[FN_GET.len()..]
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),
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))
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}
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("name", Some(s)) if s.value().starts_with(FN_SET) => {
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return Err(syn::Error::new(
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item_span,
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format!(
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"use attribute 'setter = \"{}\"' instead",
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&s.value()[FN_SET.len()..]
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),
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))
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}
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("name", Some(s)) => name.push(s.value()),
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("index_get", Some(s))
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| ("index_set", Some(s))
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| ("return_raw", Some(s))
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| ("pure", Some(s))
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| ("skip", Some(s))
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| ("global", Some(s))
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| ("internal", Some(s)) => {
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return Err(syn::Error::new(s.span(), "extraneous value"))
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}
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("pure", None) => pure = Some(item_span),
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("return_raw", None) => return_raw = Some(item_span),
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("skip", None) => skip = true,
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("global", None) => match namespace {
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FnNamespaceAccess::Unset => namespace = FnNamespaceAccess::Global,
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FnNamespaceAccess::Global => (),
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FnNamespaceAccess::Internal => {
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return Err(syn::Error::new(
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key.span(),
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"namespace is already set to 'internal'",
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))
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}
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},
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("internal", None) => match namespace {
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FnNamespaceAccess::Unset => namespace = FnNamespaceAccess::Internal,
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FnNamespaceAccess::Internal => (),
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FnNamespaceAccess::Global => {
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return Err(syn::Error::new(
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key.span(),
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"namespace is already set to 'global'",
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))
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}
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},
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("get", Some(s)) => {
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special = match special {
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FnSpecialAccess::None => FnSpecialAccess::Property(Property::Get(
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syn::Ident::new(&s.value(), s.span()),
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)),
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_ => return Err(syn::Error::new(item_span.span(), "conflicting getter")),
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}
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}
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("set", Some(s)) => {
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special = match special {
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FnSpecialAccess::None => FnSpecialAccess::Property(Property::Set(
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syn::Ident::new(&s.value(), s.span()),
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)),
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_ => return Err(syn::Error::new(item_span.span(), "conflicting setter")),
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}
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}
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("index_get", None) => {
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special = match special {
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FnSpecialAccess::None => FnSpecialAccess::Index(Index::Get),
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_ => {
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return Err(syn::Error::new(item_span.span(), "conflicting index_get"))
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}
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}
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}
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("index_set", None) => {
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special = match special {
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FnSpecialAccess::None => FnSpecialAccess::Index(Index::Set),
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_ => {
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return Err(syn::Error::new(item_span.span(), "conflicting index_set"))
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}
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}
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}
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(attr, ..) => {
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return Err(syn::Error::new(
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key.span(),
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format!("unknown attribute '{}'", attr),
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))
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}
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}
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}
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Ok(ExportedFnParams {
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name,
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return_raw,
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pure,
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skip,
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special,
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namespace,
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span: Some(span),
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})
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}
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}
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#[derive(Debug)]
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pub struct ExportedFn {
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entire_span: Span,
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signature: syn::Signature,
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visibility: syn::Visibility,
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pass_context: bool,
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mut_receiver: bool,
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params: ExportedFnParams,
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cfg_attrs: Vec<syn::Attribute>,
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#[cfg(feature = "metadata")]
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comments: Vec<String>,
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}
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impl Parse for ExportedFn {
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fn parse(input: ParseStream) -> syn::Result<Self> {
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let fn_all: syn::ItemFn = input.parse()?;
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let entire_span = fn_all.span();
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let str_type_path = syn::parse2::<syn::Path>(quote! { str }).unwrap();
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let context_type_path1 = syn::parse2::<syn::Path>(quote! { NativeCallContext }).unwrap();
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let context_type_path2 =
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syn::parse2::<syn::Path>(quote! { rhai::NativeCallContext }).unwrap();
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let mut pass_context = false;
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let cfg_attrs = crate::attrs::collect_cfg_attr(&fn_all.attrs);
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let visibility = fn_all.vis;
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// Determine if the function requires a call context
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match fn_all.sig.inputs.first() {
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Some(syn::FnArg::Typed(syn::PatType { ref ty, .. })) => {
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match flatten_type_groups(ty.as_ref()) {
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syn::Type::Path(p)
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if p.path == context_type_path1 || p.path == context_type_path2 =>
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{
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pass_context = true;
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}
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_ => {}
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}
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}
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_ => {}
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}
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let skip_slots = if pass_context { 1 } else { 0 };
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// Determine whether function generates a special calling convention for a mutable receiver.
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let mut_receiver = match fn_all.sig.inputs.iter().nth(skip_slots) {
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Some(syn::FnArg::Receiver(syn::Receiver {
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reference: Some(_), ..
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})) => true,
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Some(syn::FnArg::Typed(syn::PatType { ref ty, .. })) => {
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match flatten_type_groups(ty.as_ref()) {
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syn::Type::Reference(syn::TypeReference {
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mutability: Some(_),
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..
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}) => true,
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syn::Type::Reference(syn::TypeReference {
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mutability: None,
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ref elem,
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..
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}) => match flatten_type_groups(elem.as_ref()) {
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syn::Type::Path(ref p) if p.path == str_type_path => false,
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_ => {
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return Err(syn::Error::new(
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ty.span(),
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"references from Rhai in this position must be mutable",
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))
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}
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},
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_ => false,
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}
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}
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_ => false,
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};
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// All arguments after the first must be moved except for &str.
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for arg in fn_all.sig.inputs.iter().skip(skip_slots + 1) {
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let ty = match arg {
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syn::FnArg::Typed(syn::PatType { ref ty, .. }) => ty,
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_ => panic!("internal error: receiver argument outside of first position!?"),
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};
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let is_ok = match flatten_type_groups(ty.as_ref()) {
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syn::Type::Reference(syn::TypeReference {
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mutability: Some(_),
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..
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}) => false,
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syn::Type::Reference(syn::TypeReference {
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mutability: None,
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ref elem,
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..
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}) => {
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matches!(flatten_type_groups(elem.as_ref()), syn::Type::Path(ref p) if p.path == str_type_path)
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}
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syn::Type::Verbatim(..) => false,
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_ => true,
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};
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if !is_ok {
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return Err(syn::Error::new(
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ty.span(),
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"function parameters other than the first one cannot be passed by reference",
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));
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}
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}
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// Check return type.
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match fn_all.sig.output {
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syn::ReturnType::Type(.., ref ret_type) => {
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match flatten_type_groups(ret_type.as_ref()) {
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syn::Type::Ptr(..) => {
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return Err(syn::Error::new(
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fn_all.sig.output.span(),
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"Rhai functions cannot return pointers",
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))
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}
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syn::Type::Reference(..) => {
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return Err(syn::Error::new(
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fn_all.sig.output.span(),
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"Rhai functions cannot return references",
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))
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}
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_ => {}
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}
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}
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_ => {}
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}
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Ok(ExportedFn {
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entire_span,
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signature: fn_all.sig,
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visibility,
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pass_context,
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mut_receiver,
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params: Default::default(),
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cfg_attrs,
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#[cfg(feature = "metadata")]
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comments: Vec::new(),
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})
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}
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}
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impl ExportedFn {
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#![allow(unused)]
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pub fn params(&self) -> &ExportedFnParams {
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&self.params
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}
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pub fn cfg_attrs(&self) -> &[syn::Attribute] {
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&self.cfg_attrs
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}
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pub fn update_scope(&mut self, parent_scope: &ExportScope) {
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let keep = match (self.params.skip, parent_scope) {
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(true, ..) => false,
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(.., ExportScope::PubOnly) => self.is_public(),
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(.., ExportScope::Prefix(s)) => self.name().to_string().starts_with(s),
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(.., ExportScope::All) => true,
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};
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self.params.skip = !keep;
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}
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pub fn skipped(&self) -> bool {
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self.params.skip
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}
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pub fn pass_context(&self) -> bool {
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self.pass_context
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}
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pub fn signature(&self) -> &syn::Signature {
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&self.signature
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}
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pub fn mutable_receiver(&self) -> bool {
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self.mut_receiver
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}
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pub fn is_public(&self) -> bool {
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!matches!(self.visibility, syn::Visibility::Inherited)
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}
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pub fn span(&self) -> &Span {
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&self.entire_span
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}
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pub fn name(&self) -> &syn::Ident {
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&self.signature.ident
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}
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pub fn exported_names(&self) -> Vec<syn::LitStr> {
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let mut literals: Vec<_> = self
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.params
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.name
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.iter()
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.map(|s| syn::LitStr::new(s, Span::call_site()))
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.collect();
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if let Some((s, _, span)) = self.params.special.get_fn_name() {
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literals.push(syn::LitStr::new(&s, span));
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}
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if literals.is_empty() {
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literals.push(syn::LitStr::new(
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&self.signature.ident.to_string(),
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self.signature.ident.span(),
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));
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}
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literals
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}
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pub fn exported_name(&self) -> Cow<str> {
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self.params
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.name
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.last()
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.map_or_else(|| self.signature.ident.to_string().into(), |s| s.into())
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}
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pub fn arg_list(&self) -> impl Iterator<Item = &syn::FnArg> {
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let skip = if self.pass_context { 1 } else { 0 };
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self.signature.inputs.iter().skip(skip)
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}
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pub fn arg_count(&self) -> usize {
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let skip = if self.pass_context { 1 } else { 0 };
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self.signature.inputs.len() - skip
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}
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pub fn return_type(&self) -> Option<&syn::Type> {
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match self.signature.output {
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syn::ReturnType::Type(.., ref ret_type) => Some(flatten_type_groups(ret_type)),
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_ => None,
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}
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}
|
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|
|
#[cfg(feature = "metadata")]
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pub fn comments(&self) -> &[String] {
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&self.comments
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}
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#[cfg(feature = "metadata")]
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pub fn set_comments(&mut self, comments: Vec<String>) {
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self.comments = comments
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}
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pub fn set_cfg_attrs(&mut self, cfg_attrs: Vec<syn::Attribute>) {
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self.cfg_attrs = cfg_attrs
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}
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pub fn set_params(&mut self, mut params: ExportedFnParams) -> syn::Result<()> {
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// Several issues are checked here to avoid issues with diagnostics caused by raising them later.
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//
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// 1a. Do not allow non-returning raw functions.
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//
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if params.return_raw.is_some() && self.return_type().is_none() {
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return Err(syn::Error::new(
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params.return_raw.unwrap(),
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"functions marked with 'return_raw' must return Result<T, Box<EvalAltResult>>",
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));
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}
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// 1b. Do not allow non-method pure functions.
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//
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if params.pure.is_some() && !self.mutable_receiver() {
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return Err(syn::Error::new(
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params.pure.unwrap(),
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"'pure' is not necessary on functions without a &mut first parameter",
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));
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}
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|
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match params.special {
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// 2a. Property getters must take only the subject as an argument.
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|
FnSpecialAccess::Property(Property::Get(..)) if self.arg_count() != 1 => {
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|
return Err(syn::Error::new(
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self.signature.inputs.span(),
|
|
"property getter requires exactly 1 parameter",
|
|
))
|
|
}
|
|
// 2b. Property getters must return a value.
|
|
FnSpecialAccess::Property(Property::Get(..)) if self.return_type().is_none() => {
|
|
return Err(syn::Error::new(
|
|
self.signature.span(),
|
|
"property getter must return a value",
|
|
))
|
|
}
|
|
// 3a. Property setters must take the subject and a new value as arguments.
|
|
FnSpecialAccess::Property(Property::Set(..)) if self.arg_count() != 2 => {
|
|
return Err(syn::Error::new(
|
|
self.signature.inputs.span(),
|
|
"property setter requires exactly 2 parameters",
|
|
))
|
|
}
|
|
// 3b. Non-raw property setters must return nothing.
|
|
FnSpecialAccess::Property(Property::Set(..))
|
|
if params.return_raw.is_none() && self.return_type().is_some() =>
|
|
{
|
|
return Err(syn::Error::new(
|
|
self.signature.output.span(),
|
|
"property setter cannot return any value",
|
|
))
|
|
}
|
|
// 4a. Index getters must take the subject and the accessed "index" as arguments.
|
|
FnSpecialAccess::Index(Index::Get) if self.arg_count() != 2 => {
|
|
return Err(syn::Error::new(
|
|
self.signature.inputs.span(),
|
|
"index getter requires exactly 2 parameters",
|
|
))
|
|
}
|
|
// 4b. Index getters must return a value.
|
|
FnSpecialAccess::Index(Index::Get) if self.return_type().is_none() => {
|
|
return Err(syn::Error::new(
|
|
self.signature.span(),
|
|
"index getter must return a value",
|
|
))
|
|
}
|
|
// 5a. Index setters must take the subject, "index", and new value as arguments.
|
|
FnSpecialAccess::Index(Index::Set) if self.arg_count() != 3 => {
|
|
return Err(syn::Error::new(
|
|
self.signature.inputs.span(),
|
|
"index setter requires exactly 3 parameters",
|
|
))
|
|
}
|
|
// 5b. Non-raw index setters must return nothing.
|
|
FnSpecialAccess::Index(Index::Set)
|
|
if params.return_raw.is_none() && self.return_type().is_some() =>
|
|
{
|
|
return Err(syn::Error::new(
|
|
self.signature.output.span(),
|
|
"index setter cannot return any value",
|
|
))
|
|
}
|
|
_ => {}
|
|
}
|
|
|
|
self.params = params;
|
|
Ok(())
|
|
}
|
|
|
|
pub fn generate(self) -> TokenStream {
|
|
let name: syn::Ident =
|
|
syn::Ident::new(&format!("rhai_fn_{}", self.name()), self.name().span());
|
|
let impl_block = self.generate_impl("Token");
|
|
let dyn_result_fn_block = self.generate_dynamic_fn();
|
|
let vis = self.visibility;
|
|
quote! {
|
|
#[automatically_derived]
|
|
#vis mod #name {
|
|
use super::*;
|
|
pub struct Token();
|
|
#impl_block
|
|
#dyn_result_fn_block
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn generate_dynamic_fn(&self) -> TokenStream {
|
|
let name = self.name().clone();
|
|
|
|
let mut dynamic_signature = self.signature.clone();
|
|
dynamic_signature.ident = syn::Ident::new("dynamic_result_fn", Span::call_site());
|
|
dynamic_signature.output = syn::parse2::<syn::ReturnType>(quote! {
|
|
-> RhaiResult
|
|
})
|
|
.unwrap();
|
|
let arguments: Vec<_> = dynamic_signature
|
|
.inputs
|
|
.iter()
|
|
.filter_map(|fn_arg| match fn_arg {
|
|
syn::FnArg::Typed(syn::PatType { ref pat, .. }) => match pat.as_ref() {
|
|
syn::Pat::Ident(ref ident) => Some(ident.ident.clone()),
|
|
_ => None,
|
|
},
|
|
_ => None,
|
|
})
|
|
.collect();
|
|
|
|
let return_span = self
|
|
.return_type()
|
|
.map(|r| r.span())
|
|
.unwrap_or_else(Span::call_site);
|
|
if self.params.return_raw.is_some() {
|
|
quote_spanned! { return_span =>
|
|
pub #dynamic_signature {
|
|
#name(#(#arguments),*).map(Dynamic::from)
|
|
}
|
|
}
|
|
} else {
|
|
quote_spanned! { return_span =>
|
|
#[allow(unused)]
|
|
#[inline(always)]
|
|
pub #dynamic_signature {
|
|
Ok(Dynamic::from(#name(#(#arguments),*)))
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn generate_impl(&self, on_type_name: &str) -> TokenStream {
|
|
let sig_name = self.name().clone();
|
|
let arg_count = self.arg_count();
|
|
let is_method_call = self.mutable_receiver();
|
|
|
|
let mut unpack_statements = Vec::new();
|
|
let mut unpack_exprs = Vec::new();
|
|
#[cfg(feature = "metadata")]
|
|
let mut input_type_names = Vec::new();
|
|
let mut input_type_exprs = Vec::new();
|
|
|
|
let return_type = self
|
|
.return_type()
|
|
.map(print_type)
|
|
.unwrap_or_else(|| "()".to_string());
|
|
|
|
let skip_first_arg;
|
|
|
|
if self.pass_context {
|
|
unpack_exprs.push(syn::parse2::<syn::Expr>(quote! { context }).unwrap());
|
|
}
|
|
|
|
// Handle the first argument separately if the function has a "method like" receiver
|
|
if is_method_call {
|
|
skip_first_arg = true;
|
|
let first_arg = self.arg_list().next().unwrap();
|
|
let var = syn::Ident::new("arg0", Span::call_site());
|
|
match first_arg {
|
|
syn::FnArg::Typed(syn::PatType { pat, ty, .. }) => {
|
|
#[cfg(feature = "metadata")]
|
|
let arg_name = format!("{}: {}", pat.to_token_stream(), print_type(ty));
|
|
let arg_type = match flatten_type_groups(ty.as_ref()) {
|
|
syn::Type::Reference(syn::TypeReference { ref elem, .. }) => elem.as_ref(),
|
|
p => p,
|
|
};
|
|
let downcast_span = quote_spanned!(arg_type.span() =>
|
|
&mut args[0usize].write_lock::<#arg_type>().unwrap()
|
|
);
|
|
unpack_statements.push(
|
|
syn::parse2::<syn::Stmt>(quote! {
|
|
let #var = #downcast_span;
|
|
})
|
|
.unwrap(),
|
|
);
|
|
if self.params().pure.is_none() {
|
|
let arg_lit_str =
|
|
syn::LitStr::new(&pat.to_token_stream().to_string(), pat.span());
|
|
unpack_statements.push(
|
|
syn::parse2::<syn::Stmt>(quote! {
|
|
if args[0usize].is_read_only() {
|
|
return Err(EvalAltResult::ErrorAssignmentToConstant(#arg_lit_str.to_string(), Position::NONE).into());
|
|
}
|
|
})
|
|
.unwrap(),
|
|
);
|
|
}
|
|
#[cfg(feature = "metadata")]
|
|
input_type_names.push(arg_name);
|
|
input_type_exprs.push(
|
|
syn::parse2::<syn::Expr>(quote_spanned!(arg_type.span() =>
|
|
TypeId::of::<#arg_type>()
|
|
))
|
|
.unwrap(),
|
|
);
|
|
}
|
|
syn::FnArg::Receiver(..) => todo!("true self parameters not implemented yet"),
|
|
}
|
|
unpack_exprs.push(syn::parse2::<syn::Expr>(quote! { #var }).unwrap());
|
|
} else {
|
|
skip_first_arg = false;
|
|
}
|
|
|
|
// Handle the rest of the arguments, which all are passed by value.
|
|
//
|
|
// The only exception is strings, which need to be downcast to ImmutableString to enable a
|
|
// zero-copy conversion to &str by reference, or a cloned String.
|
|
let str_type_path = syn::parse2::<syn::Path>(quote! { str }).unwrap();
|
|
let string_type_path = syn::parse2::<syn::Path>(quote! { String }).unwrap();
|
|
for (i, arg) in self.arg_list().enumerate().skip(skip_first_arg as usize) {
|
|
let var = syn::Ident::new(&format!("arg{}", i), Span::call_site());
|
|
let is_string;
|
|
let is_ref;
|
|
match arg {
|
|
syn::FnArg::Typed(syn::PatType { pat, ty, .. }) => {
|
|
#[cfg(feature = "metadata")]
|
|
let arg_name = format!("{}: {}", pat.to_token_stream(), print_type(ty));
|
|
let arg_type = ty.as_ref();
|
|
let downcast_span = match flatten_type_groups(arg_type) {
|
|
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 => {
|
|
is_string = true;
|
|
is_ref = true;
|
|
quote_spanned!(arg_type.span() =>
|
|
mem::take(args[#i]).into_immutable_string().unwrap()
|
|
)
|
|
}
|
|
_ => panic!("internal error: why wasn't this found earlier!?"),
|
|
},
|
|
syn::Type::Path(ref p) if p.path == string_type_path => {
|
|
is_string = true;
|
|
is_ref = false;
|
|
quote_spanned!(arg_type.span() =>
|
|
mem::take(args[#i]).into_string().unwrap()
|
|
)
|
|
}
|
|
_ => {
|
|
is_string = false;
|
|
is_ref = false;
|
|
quote_spanned!(arg_type.span() =>
|
|
mem::take(args[#i]).cast::<#arg_type>()
|
|
)
|
|
}
|
|
};
|
|
|
|
unpack_statements.push(
|
|
syn::parse2::<syn::Stmt>(quote! {
|
|
let #var = #downcast_span;
|
|
})
|
|
.unwrap(),
|
|
);
|
|
#[cfg(feature = "metadata")]
|
|
input_type_names.push(arg_name);
|
|
if !is_string {
|
|
input_type_exprs.push(
|
|
syn::parse2::<syn::Expr>(quote_spanned!(arg_type.span() =>
|
|
TypeId::of::<#arg_type>()
|
|
))
|
|
.unwrap(),
|
|
);
|
|
} else {
|
|
input_type_exprs.push(
|
|
syn::parse2::<syn::Expr>(quote_spanned!(arg_type.span() =>
|
|
TypeId::of::<ImmutableString>()
|
|
))
|
|
.unwrap(),
|
|
);
|
|
}
|
|
}
|
|
syn::FnArg::Receiver(..) => panic!("internal error: how did this happen!?"),
|
|
}
|
|
if !is_ref {
|
|
unpack_exprs.push(syn::parse2::<syn::Expr>(quote! { #var }).unwrap());
|
|
} else {
|
|
unpack_exprs.push(syn::parse2::<syn::Expr>(quote! { &#var }).unwrap());
|
|
}
|
|
}
|
|
|
|
// In method calls, the first argument will need to be mutably borrowed. Because Rust marks
|
|
// that as needing to borrow the entire array, all of the previous argument unpacking via
|
|
// clone needs to happen first.
|
|
if is_method_call {
|
|
let arg0 = unpack_statements.remove(0);
|
|
unpack_statements.push(arg0);
|
|
}
|
|
|
|
// Handle "raw returns", aka cases where the result is a dynamic or an error.
|
|
//
|
|
// This allows skipping the Dynamic::from wrap.
|
|
let return_span = self
|
|
.return_type()
|
|
.map(|r| r.span())
|
|
.unwrap_or_else(Span::call_site);
|
|
let return_expr = if self.params.return_raw.is_none() {
|
|
quote_spanned! { return_span =>
|
|
Ok(Dynamic::from(#sig_name(#(#unpack_exprs),*)))
|
|
}
|
|
} else {
|
|
quote_spanned! { return_span =>
|
|
#sig_name(#(#unpack_exprs),*).map(Dynamic::from)
|
|
}
|
|
};
|
|
|
|
let type_name = syn::Ident::new(on_type_name, Span::call_site());
|
|
|
|
#[cfg(feature = "metadata")]
|
|
let param_names = quote! {
|
|
pub const PARAM_NAMES: &'static [&'static str] = &[#(#input_type_names,)* #return_type];
|
|
};
|
|
#[cfg(not(feature = "metadata"))]
|
|
let param_names = quote! {};
|
|
|
|
let cfg_attrs: Vec<_> = self
|
|
.cfg_attrs()
|
|
.iter()
|
|
.map(syn::Attribute::to_token_stream)
|
|
.collect();
|
|
|
|
quote! {
|
|
#(#cfg_attrs)*
|
|
impl #type_name {
|
|
#param_names
|
|
#[inline(always)] pub fn param_types() -> [TypeId; #arg_count] { [#(#input_type_exprs),*] }
|
|
}
|
|
#(#cfg_attrs)*
|
|
impl PluginFunction for #type_name {
|
|
#[inline(always)]
|
|
fn call(&self, context: NativeCallContext, args: &mut [&mut Dynamic]) -> RhaiResult {
|
|
#(#unpack_statements)*
|
|
#return_expr
|
|
}
|
|
|
|
#[inline(always)] fn is_method_call(&self) -> bool { #is_method_call }
|
|
}
|
|
}
|
|
}
|
|
}
|