WIP: use HdlOption[the_type_var] or UInt[123 + n] for creating types

crates/fayalite-proc-macros-impl/src/hdl_bundle.rs

@@ -0,0 +1,339 @@
+use crate::{
+    hdl_type_common::{get_target, type_derives, TypeOptions, WrappedInConst},
+    kw, Errors, HdlAttr,
+};
+use proc_macro2::TokenStream;
+use quote::{format_ident, quote_spanned, ToTokens};
+use syn::{
+    parse_quote_spanned, punctuated::Punctuated, spanned::Spanned, token::Brace, Attribute, Field,
+    Fields, FieldsNamed, Generics, Ident, ItemStruct, Token, Visibility,
+};
+
+#[derive(Clone, Debug)]
+pub struct ParsedBundle {
+    pub(crate) attrs: Vec<Attribute>,
+    pub(crate) options: HdlAttr<TypeOptions>,
+    pub(crate) vis: Visibility,
+    pub(crate) struct_token: Token![struct],
+    pub(crate) ident: Ident,
+    pub(crate) generics: Generics,
+    pub(crate) fields: FieldsNamed,
+    pub(crate) field_flips: Vec<Option<HdlAttr<kw::flip>>>,
+    pub(crate) mask_type_ident: Ident,
+    pub(crate) mask_type_match_variant_ident: Ident,
+    pub(crate) match_variant_ident: Ident,
+}
+
+impl ParsedBundle {
+    fn parse_field(
+        errors: &mut Errors,
+        field: &mut Field,
+        index: usize,
+    ) -> Option<HdlAttr<kw::flip>> {
+        let Field {
+            attrs,
+            vis: _,
+            mutability: _,
+            ident,
+            colon_token,
+            ty,
+        } = field;
+        let ident = ident.get_or_insert_with(|| format_ident!("_{index}", span = ty.span()));
+        colon_token.get_or_insert(Token![:](ident.span()));
+        let options = errors.unwrap_or_default(HdlAttr::parse_and_take_attr(attrs));
+        options
+    }
+    fn parse(item: ItemStruct) -> syn::Result<Self> {
+        let ItemStruct {
+            mut attrs,
+            vis,
+            struct_token,
+            ident,
+            generics,
+            fields,
+            semi_token,
+        } = item;
+        let mut errors = Errors::new();
+        let options = errors
+            .unwrap_or_default(HdlAttr::parse_and_take_attr(&mut attrs))
+            .unwrap_or_default();
+        let mut fields = match fields {
+            syn::Fields::Named(fields) => fields,
+            syn::Fields::Unnamed(fields) => {
+                errors.error(&fields, "#[hdl] struct must use curly braces: {}");
+                FieldsNamed {
+                    brace_token: Brace(fields.paren_token.span),
+                    named: fields.unnamed,
+                }
+            }
+            syn::Fields::Unit => {
+                errors.error(&fields, "#[hdl] struct must use curly braces: {}");
+                FieldsNamed {
+                    brace_token: Brace(semi_token.unwrap_or_default().span),
+                    named: Punctuated::default(),
+                }
+            }
+        };
+        let mut field_flips = Vec::with_capacity(fields.named.len());
+        for (index, field) in fields.named.iter_mut().enumerate() {
+            field_flips.push(Self::parse_field(&mut errors, field, index));
+        }
+        errors.finish()?;
+        Ok(Self {
+            attrs,
+            options,
+            vis,
+            struct_token,
+            generics,
+            fields,
+            field_flips,
+            mask_type_ident: format_ident!("__{ident}__MaskType"),
+            mask_type_match_variant_ident: format_ident!("__{ident}__MaskType__MatchVariant"),
+            match_variant_ident: format_ident!("__{ident}__MatchVariant"),
+            ident,
+        })
+    }
+}
+
+impl ToTokens for ParsedBundle {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        let Self {
+            attrs,
+            options,
+            vis,
+            struct_token,
+            ident,
+            generics,
+            fields,
+            field_flips,
+            mask_type_ident,
+            mask_type_match_variant_ident,
+            match_variant_ident,
+        } = self;
+        let TypeOptions {
+            outline_generated: _,
+            connect_inexact,
+            target,
+        } = &options.body;
+        let target = get_target(target, ident);
+        let mut item_attrs = attrs.clone();
+        item_attrs.push(type_derives(ident.span()));
+        ItemStruct {
+            attrs: item_attrs,
+            vis: vis.clone(),
+            struct_token: *struct_token,
+            ident: ident.clone(),
+            generics: generics.clone(),
+            fields: Fields::Named(fields.clone()),
+            semi_token: None,
+        }
+        .to_tokens(tokens);
+        let (impl_generics, type_generics, where_clause) = generics.split_for_impl();
+        let mut wrapped_in_const = WrappedInConst::new(tokens, ident.span());
+        let tokens = wrapped_in_const.inner();
+        let mut mask_type_fields = fields.clone();
+        for Field { ident, ty, .. } in &mut mask_type_fields.named {
+            let ident = ident.as_ref().unwrap();
+            *ty = parse_quote_spanned! {ident.span()=>
+                <#ty as ::fayalite::ty::Type>::MaskType
+            };
+        }
+        ItemStruct {
+            attrs: vec![
+                parse_quote_spanned! {ident.span()=>
+                    #[allow(non_camel_case_types)]
+                },
+                type_derives(ident.span()),
+            ],
+            vis: vis.clone(),
+            struct_token: *struct_token,
+            ident: mask_type_ident.clone(),
+            generics: generics.clone(),
+            fields: Fields::Named(mask_type_fields.clone()),
+            semi_token: None,
+        }
+        .to_tokens(tokens);
+        let mut mask_type_match_variant_fields = mask_type_fields;
+        for Field { ident, ty, .. } in &mut mask_type_match_variant_fields.named {
+            let ident = ident.as_ref().unwrap();
+            *ty = parse_quote_spanned! {ident.span()=>
+                ::fayalite::expr::Expr<#ty>
+            };
+        }
+        ItemStruct {
+            attrs: vec![parse_quote_spanned! {ident.span()=>
+                #[allow(non_camel_case_types)]
+            }],
+            vis: vis.clone(),
+            struct_token: *struct_token,
+            ident: mask_type_match_variant_ident.clone(),
+            generics: generics.clone(),
+            fields: Fields::Named(mask_type_match_variant_fields),
+            semi_token: None,
+        }
+        .to_tokens(tokens);
+        let mut match_variant_fields = fields.clone();
+        for Field { ident, ty, .. } in &mut match_variant_fields.named {
+            let ident = ident.as_ref().unwrap();
+            *ty = parse_quote_spanned! {ident.span()=>
+                ::fayalite::expr::Expr<#ty>
+            };
+        }
+        ItemStruct {
+            attrs: vec![parse_quote_spanned! {ident.span()=>
+                #[allow(non_camel_case_types)]
+            }],
+            vis: vis.clone(),
+            struct_token: *struct_token,
+            ident: match_variant_ident.clone(),
+            generics: generics.clone(),
+            fields: Fields::Named(match_variant_fields),
+            semi_token: None,
+        }
+        .to_tokens(tokens);
+        let match_variant_body_fields =
+            Vec::from_iter(fields.named.iter().map(|Field { ident, .. }| {
+                let ident: &Ident = ident.as_ref().unwrap();
+                let ident_str = ident.to_string();
+                quote_spanned! {ident.span()=>
+                    #ident: ::fayalite::expr::Expr::field(this, #ident_str),
+                }
+            }));
+        let mask_type_body_fields =
+            Vec::from_iter(fields.named.iter().map(|Field { ident, .. }| {
+                let ident: &Ident = ident.as_ref().unwrap();
+                quote_spanned! {ident.span()=>
+                    #ident: ::fayalite::ty::Type::mask_type(&self.#ident),
+                }
+            }));
+        let from_canonical_body_fields = Vec::from_iter(fields.named.iter().enumerate().zip(field_flips).map(
+            |((index, Field { ident, .. }), flip)| {
+                let ident: &Ident = ident.as_ref().unwrap();
+                let ident_str = ident.to_string();
+                let flipped = flip.is_some();
+                quote_spanned! {ident.span()=>
+                    #ident: {
+                        let ::fayalite::bundle::BundleField { name, flipped, ty } = fields[#index];
+                        ::fayalite::__std::assert_eq!(&*name, #ident_str);
+                        ::fayalite::__std::assert_eq!(flipped, #flipped);
+                        ::fayalite::ty::Type::from_canonical(ty)
+                    },
+                }
+            },
+        ));
+        let fields_len = fields.named.len();
+        quote_spanned! {ident.span()=>
+            #[automatically_derived]
+            impl #impl_generics ::fayalite::ty::Type for #mask_type_ident #type_generics
+            #where_clause
+            {
+                type MaskType = #mask_type_ident #type_generics;
+                type MatchVariant = #mask_type_match_variant_ident #type_generics;
+                type MatchActiveScope = ();
+                type MatchVariantAndInactiveScope = MatchVariantWithoutScope<
+                    <Self as ::fayalite::ty::Type>::MatchVariant,
+                >;
+                type MatchVariantsIter = ::fayalite::__std::iter::Once<
+                    <Self as ::fayalite::ty::Type>::MatchVariantAndInactiveScope,
+                >;
+                fn match_variants(
+                    this: ::fayalite::expr::Expr<Self>,
+                    module_builder: &mut ::fayalite::module::ModuleBuilder<
+                        ::fayalite::module::NormalModule,
+                    >,
+                    source_location: ::fayalite::source_location::SourceLocation,
+                ) -> <Self as ::fayalite::ty::Type>::MatchVariantsIter {
+                    let _ = this;
+                    let _ = module_builder;
+                    let _ = source_location;
+                    let retval = #mask_type_match_variant_ident {
+                        #(#match_variant_body_fields)*
+                    };
+                    ::fayalite::__std::iter::once(::fayalite::ty::MatchVariantWithoutScope(retval))
+                }
+                fn mask_type(&self) -> <Self as ::fayalite::ty::Type>::MaskType {
+                    *self
+                }
+                fn canonical(&self) -> ::fayalite::ty::CanonicalType {
+                    ::fayalite::ty::Type::canonical(&::fayalite::bundle::Bundle::new(::fayalite::bundle::BundleType::fields(self)))
+                }
+                #[track_caller]
+                fn from_canonical(canonical_type: ::fayalite::ty::CanonicalType) -> Self {
+                    let ::fayalite::ty::CanonicalType::Bundle(bundle) = canonical_type else {
+                        ::fayalite::__std::panic!("expected bundle");
+                    };
+                    let fields = ::fayalite::bundle::BundleType::fields(&bundle);
+                    ::fayalite::__std::assert_eq!(fields.len(), #fields_len, "bundle has wrong number of fields");
+                    Self {
+                        #(#from_canonical_body_fields)*
+                    }
+                }
+                fn source_location() -> ::fayalite::source_location::SourceLocation {
+                    ::fayalite::source_location::SourceLocation::caller()
+                }
+            }
+            #[automatically_derived]
+            impl #impl_generics ::fayalite::ty::Type for #target #type_generics
+            #where_clause
+            {
+                type MaskType = #mask_type_ident #type_generics;
+                type MatchVariant = #match_variant_ident #type_generics;
+                type MatchActiveScope = ();
+                type MatchVariantAndInactiveScope = MatchVariantWithoutScope<
+                    <Self as ::fayalite::ty::Type>::MatchVariant,
+                >;
+                type MatchVariantsIter = ::fayalite::__std::iter::Once<
+                    <Self as ::fayalite::ty::Type>::MatchVariantAndInactiveScope,
+                >;
+                fn match_variants(
+                    this: ::fayalite::expr::Expr<Self>,
+                    module_builder: &mut ::fayalite::module::ModuleBuilder<
+                        ::fayalite::module::NormalModule,
+                    >,
+                    source_location: ::fayalite::source_location::SourceLocation,
+                ) -> <Self as ::fayalite::ty::Type>::MatchVariantsIter {
+                    let _ = this;
+                    let _ = module_builder;
+                    let _ = source_location;
+                    let retval = #mask_type_match_variant_ident {
+                        #(#match_variant_body_fields)*
+                    };
+                    ::fayalite::__std::iter::once(::fayalite::ty::MatchVariantWithoutScope(retval))
+                }
+                fn mask_type(&self) -> <Self as ::fayalite::ty::Type>::MaskType {
+                    #mask_type_ident {
+                        #(#mask_type_body_fields)*
+                    }
+                }
+                fn canonical(&self) -> ::fayalite::ty::CanonicalType {
+                    ::fayalite::ty::Type::canonical(&::fayalite::bundle::Bundle::new(::fayalite::bundle::BundleType::fields(self)))
+                }
+                #[track_caller]
+                fn from_canonical(canonical_type: ::fayalite::ty::CanonicalType) -> Self {
+                    let ::fayalite::ty::CanonicalType::Bundle(bundle) = canonical_type else {
+                        ::fayalite::__std::panic!("expected bundle");
+                    };
+                    let fields = ::fayalite::bundle::BundleType::fields(&bundle);
+                    ::fayalite::__std::assert_eq!(fields.len(), #fields_len, "bundle has wrong number of fields");
+                    Self {
+                        #(#from_canonical_body_fields)*
+                    }
+                }
+                fn source_location() -> ::fayalite::source_location::SourceLocation {
+                    ::fayalite::source_location::SourceLocation::caller()
+                }
+            }
+        }
+        .to_tokens(tokens);
+    }
+}
+
+pub(crate) fn hdl_bundle(item: ItemStruct) -> syn::Result<TokenStream> {
+    let item = ParsedBundle::parse(item)?;
+    let outline_generated = item.options.body.outline_generated;
+    let mut contents = item.to_token_stream();
+    if outline_generated.is_some() {
+        contents = crate::outline_generated(contents, "hdl-bundle-");
+    }
+    Ok(contents)
+}