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

775 lines
26 KiB
Rust

// SPDX-License-Identifier: LGPL-3.0-or-later
// See Notices.txt for copyright information
use crate::{fold::impl_fold, kw, Errors, HdlAttr};
use proc_macro2::{Span, TokenStream};
use quote::{format_ident, quote, quote_spanned, ToTokens};
use std::collections::{BTreeMap, HashMap, HashSet};
use syn::{
fold::{fold_generics, Fold},
parse::{Parse, ParseStream},
parse_quote, parse_quote_spanned,
punctuated::Punctuated,
spanned::Spanned,
token::{Brace, Paren, Where},
Block, ConstParam, Expr, Field, Fields, FieldsNamed, FieldsUnnamed, GenericParam, Generics,
Ident, Index, ItemImpl, Lifetime, LifetimeParam, Member, Path, Token, Type, TypeParam,
TypePath, Visibility, WhereClause, WherePredicate,
};
#[derive(Clone, Debug)]
pub(crate) struct Bounds(pub(crate) Punctuated<WherePredicate, Token![,]>);
impl_fold! {
struct Bounds<>(Punctuated<WherePredicate, Token![,]>);
}
impl Parse for Bounds {
fn parse(input: ParseStream) -> syn::Result<Self> {
Ok(Bounds(Punctuated::parse_terminated(input)?))
}
}
impl From<Option<WhereClause>> for Bounds {
fn from(value: Option<WhereClause>) -> Self {
Self(value.map_or_else(Punctuated::new, |v| v.predicates))
}
}
impl ToTokens for Bounds {
fn to_tokens(&self, tokens: &mut TokenStream) {
self.0.to_tokens(tokens)
}
}
#[derive(Debug, Clone)]
pub(crate) struct ParsedField<O> {
pub(crate) options: HdlAttr<O>,
pub(crate) vis: Visibility,
pub(crate) name: Member,
pub(crate) ty: Type,
}
impl<O> ParsedField<O> {
pub(crate) fn var_name(&self) -> Ident {
format_ident!("__v_{}", self.name)
}
}
pub(crate) fn get_field_name(
index: usize,
name: Option<Ident>,
ty_span: impl FnOnce() -> Span,
) -> Member {
match name {
Some(name) => Member::Named(name),
None => Member::Unnamed(Index {
index: index as _,
span: ty_span(),
}),
}
}
pub(crate) fn get_field_names(fields: &Fields) -> impl Iterator<Item = Member> + '_ {
fields
.iter()
.enumerate()
.map(|(index, field)| get_field_name(index, field.ident.clone(), || field.ty.span()))
}
impl<O: Parse + Default> ParsedField<O> {
pub(crate) fn parse_fields(
errors: &mut Errors,
fields: &mut Fields,
in_enum: bool,
) -> (FieldsKind, Vec<ParsedField<O>>) {
let mut unit_fields = Punctuated::new();
let (fields_kind, fields) = match fields {
Fields::Named(fields) => (FieldsKind::Named(fields.brace_token), &mut fields.named),
Fields::Unnamed(fields) => {
(FieldsKind::Unnamed(fields.paren_token), &mut fields.unnamed)
}
Fields::Unit => (FieldsKind::Unit, &mut unit_fields),
};
let fields = fields
.iter_mut()
.enumerate()
.map(|(index, field)| {
let options = errors
.unwrap_or_default(HdlAttr::parse_and_take_attr(&mut field.attrs))
.unwrap_or_default();
let name = get_field_name(index, field.ident.clone(), || field.ty.span());
if in_enum && !matches!(field.vis, Visibility::Inherited) {
errors.error(&field.vis, "field visibility not allowed in enums");
}
ParsedField {
options,
vis: field.vis.clone(),
name,
ty: field.ty.clone(),
}
})
.collect();
(fields_kind, fields)
}
}
#[derive(Copy, Clone, Debug)]
pub(crate) enum FieldsKind {
Unit,
Named(Brace),
Unnamed(Paren),
}
impl FieldsKind {
pub(crate) fn into_fields_named(
brace_token: Brace,
fields: impl IntoIterator<Item = syn::Field>,
) -> Fields {
Fields::Named(FieldsNamed {
brace_token,
named: Punctuated::from_iter(fields),
})
}
pub(crate) fn into_fields_unnamed(
paren_token: Paren,
fields: impl IntoIterator<Item = syn::Field>,
) -> Fields {
Fields::Unnamed(FieldsUnnamed {
paren_token,
unnamed: Punctuated::from_iter(fields),
})
}
pub(crate) fn into_fields(self, fields: impl IntoIterator<Item = syn::Field>) -> Fields {
match self {
FieldsKind::Unit => {
let mut fields = fields.into_iter().peekable();
let Some(first_field) = fields.peek() else {
return Fields::Unit;
};
if first_field.ident.is_some() {
Self::into_fields_named(Default::default(), fields)
} else {
Self::into_fields_unnamed(Default::default(), fields)
}
}
FieldsKind::Named(brace_token) => Self::into_fields_named(brace_token, fields),
FieldsKind::Unnamed(paren_token) => Self::into_fields_unnamed(paren_token, fields),
}
}
}
pub(crate) fn get_target(target: &Option<(kw::target, Paren, Path)>, item_ident: &Ident) -> Path {
match target {
Some((_, _, target)) => target.clone(),
None => item_ident.clone().into(),
}
}
pub(crate) struct ValueDeriveGenerics {
pub(crate) generics: Generics,
pub(crate) static_type_generics: Generics,
}
impl ValueDeriveGenerics {
pub(crate) fn get(mut generics: Generics, where_: &Option<(Where, Paren, Bounds)>) -> Self {
let mut static_type_generics = generics.clone();
if let Some((_, _, bounds)) = where_ {
generics
.make_where_clause()
.predicates
.extend(bounds.0.iter().cloned());
static_type_generics
.where_clause
.clone_from(&generics.where_clause);
} else {
let type_params = Vec::from_iter(generics.type_params().map(|v| v.ident.clone()));
let predicates = &mut generics.make_where_clause().predicates;
let static_type_predicates = &mut static_type_generics.make_where_clause().predicates;
for type_param in type_params {
predicates.push(parse_quote! {#type_param: ::fayalite::ty::Value});
predicates.push(parse_quote! {
<#type_param as ::fayalite::expr::ToExpr>::Type:
::fayalite::ty::Type<Value = #type_param>
});
static_type_predicates.push(parse_quote! {#type_param: ::fayalite::ty::Value});
static_type_predicates.push(parse_quote! {
<#type_param as ::fayalite::expr::ToExpr>::Type:
::fayalite::ty::StaticType<Value = #type_param>
});
static_type_predicates.push(parse_quote! {
<
<#type_param as ::fayalite::expr::ToExpr>::Type
as ::fayalite::ty::Type
>::MaskType: ::fayalite::ty::StaticType
});
}
}
Self {
generics,
static_type_generics,
}
}
}
pub(crate) fn derive_clone_hash_eq_partialeq_for_struct<Name: ToTokens>(
the_struct_ident: &Ident,
generics: &Generics,
field_names: &[Name],
) -> TokenStream {
let (impl_generics, type_generics, where_clause) = generics.split_for_impl();
quote! {
#[automatically_derived]
impl #impl_generics ::fayalite::__std::clone::Clone for #the_struct_ident #type_generics
#where_clause
{
fn clone(&self) -> Self {
Self {
#(#field_names: ::fayalite::__std::clone::Clone::clone(&self.#field_names),)*
}
}
}
#[automatically_derived]
impl #impl_generics ::fayalite::__std::hash::Hash for #the_struct_ident #type_generics
#where_clause
{
#[allow(unused_variables)]
fn hash<__H: ::fayalite::__std::hash::Hasher>(&self, hasher: &mut __H) {
#(::fayalite::__std::hash::Hash::hash(&self.#field_names, hasher);)*
}
}
#[automatically_derived]
impl #impl_generics ::fayalite::__std::cmp::Eq for #the_struct_ident #type_generics
#where_clause
{
}
#[automatically_derived]
impl #impl_generics ::fayalite::__std::cmp::PartialEq for #the_struct_ident #type_generics
#where_clause
{
#[allow(unused_variables)]
#[allow(clippy::nonminimal_bool)]
fn eq(&self, other: &Self) -> ::fayalite::__std::primitive::bool {
true #(&& ::fayalite::__std::cmp::PartialEq::eq(
&self.#field_names,
&other.#field_names,
))*
}
}
}
}
pub(crate) fn append_field(fields: &mut Fields, mut field: Field) -> Member {
let ident = field.ident.clone().expect("ident is supplied");
match fields {
Fields::Named(FieldsNamed { named, .. }) => {
named.push(field);
Member::Named(ident)
}
Fields::Unnamed(FieldsUnnamed { unnamed, .. }) => {
field.ident = None;
field.colon_token = None;
let index = unnamed.len();
unnamed.push(field);
Member::Unnamed(index.into())
}
Fields::Unit => {
*fields = Fields::Named(FieldsNamed {
brace_token: Default::default(),
named: Punctuated::from_iter([field]),
});
Member::Named(ident)
}
}
}
#[derive(Clone, Debug)]
pub(crate) struct BuilderField {
pub(crate) names: HashSet<Member>,
pub(crate) mapped_value: Expr,
pub(crate) mapped_type: Type,
pub(crate) where_clause: Option<WhereClause>,
pub(crate) builder_field_name: Ident,
pub(crate) type_param: Ident,
}
#[derive(Debug)]
pub(crate) struct Builder {
struct_name: Ident,
vis: Visibility,
fields: BTreeMap<String, BuilderField>,
}
#[derive(Debug)]
pub(crate) struct BuilderWithFields {
struct_name: Ident,
vis: Visibility,
phantom_type_param: Ident,
phantom_type_field: Ident,
fields: Vec<(String, BuilderField)>,
}
impl Builder {
pub(crate) fn new(struct_name: Ident, vis: Visibility) -> Self {
Self {
struct_name,
vis,
fields: BTreeMap::new(),
}
}
pub(crate) fn insert_field(
&mut self,
name: Member,
map_value: impl FnOnce(&Ident) -> Expr,
map_type: impl FnOnce(&Ident) -> Type,
where_clause: impl FnOnce(&Ident) -> Option<WhereClause>,
) {
self.fields
.entry(name.to_token_stream().to_string())
.or_insert_with_key(|name| {
let builder_field_name =
format_ident!("field_{}", name, span = self.struct_name.span());
let type_param = format_ident!("__T_{}", name, span = self.struct_name.span());
BuilderField {
names: HashSet::new(),
mapped_value: map_value(&builder_field_name),
mapped_type: map_type(&type_param),
where_clause: where_clause(&type_param),
builder_field_name,
type_param,
}
})
.names
.insert(name);
}
pub(crate) fn finish_filling_in_fields(self) -> BuilderWithFields {
let Self {
struct_name,
vis,
fields,
} = self;
let fields = Vec::from_iter(fields);
BuilderWithFields {
phantom_type_param: Ident::new("__Phantom", struct_name.span()),
phantom_type_field: Ident::new("__phantom", struct_name.span()),
struct_name,
vis,
fields,
}
}
}
impl BuilderWithFields {
pub(crate) fn get_field(&self, name: &Member) -> Option<(usize, &BuilderField)> {
let index = self
.fields
.binary_search_by_key(&&*name.to_token_stream().to_string(), |v| &*v.0)
.ok()?;
Some((index, &self.fields[index].1))
}
pub(crate) fn ty(
&self,
specified_fields: impl IntoIterator<Item = (Member, Type)>,
phantom_type: Option<&Type>,
other_fields_are_any_type: bool,
) -> TypePath {
let Self {
struct_name,
vis: _,
phantom_type_param,
phantom_type_field: _,
fields,
} = self;
let span = struct_name.span();
let mut arguments =
Vec::from_iter(fields.iter().map(|(_, BuilderField { type_param, .. })| {
if other_fields_are_any_type {
parse_quote_spanned! {span=>
#type_param
}
} else {
parse_quote_spanned! {span=>
()
}
}
}));
for (name, ty) in specified_fields {
let Some((index, _)) = self.get_field(&name) else {
panic!("field not found: {}", name.to_token_stream());
};
arguments[index] = ty;
}
let phantom_type_param = phantom_type.is_none().then_some(phantom_type_param);
parse_quote_spanned! {span=>
#struct_name::<#phantom_type_param #phantom_type #(, #arguments)*>
}
}
pub(crate) fn append_generics(
&self,
specified_fields: impl IntoIterator<Item = Member>,
has_phantom_type_param: bool,
other_fields_are_any_type: bool,
generics: &mut Generics,
) {
let Self {
struct_name: _,
vis: _,
phantom_type_param,
phantom_type_field: _,
fields,
} = self;
if has_phantom_type_param {
generics.params.push(GenericParam::from(TypeParam::from(
phantom_type_param.clone(),
)));
}
if !other_fields_are_any_type {
return;
}
let mut type_params = Vec::from_iter(
fields
.iter()
.map(|(_, BuilderField { type_param, .. })| Some(type_param)),
);
for name in specified_fields {
let Some((index, _)) = self.get_field(&name) else {
panic!("field not found: {}", name.to_token_stream());
};
type_params[index] = None;
}
generics.params.extend(
type_params
.into_iter()
.filter_map(|v| Some(GenericParam::from(TypeParam::from(v?.clone())))),
);
}
pub(crate) fn make_build_method(
&self,
build_fn_name: &Ident,
specified_fields: impl IntoIterator<Item = (Member, Type)>,
generics: &Generics,
phantom_type: &Type,
return_ty: &Type,
mut body: Block,
) -> ItemImpl {
let Self {
struct_name,
vis,
phantom_type_param: _,
phantom_type_field,
fields,
} = self;
let span = struct_name.span();
let field_names = Vec::from_iter(fields.iter().map(|v| &v.1.builder_field_name));
let (impl_generics, _type_generics, where_clause) = generics.split_for_impl();
let empty_arg = parse_quote_spanned! {span=>
()
};
let mut ty_arguments = vec![empty_arg; fields.len()];
let empty_field_pat = quote_spanned! {span=>
: _
};
let mut field_pats = vec![Some(empty_field_pat); fields.len()];
for (name, ty) in specified_fields {
let Some((index, _)) = self.get_field(&name) else {
panic!("field not found: {}", name.to_token_stream());
};
ty_arguments[index] = ty;
field_pats[index] = None;
}
body.stmts.insert(
0,
parse_quote_spanned! {span=>
let Self {
#(#field_names #field_pats,)*
#phantom_type_field: _,
} = self;
},
);
parse_quote_spanned! {span=>
#[automatically_derived]
impl #impl_generics #struct_name<#phantom_type #(, #ty_arguments)*>
#where_clause
{
#[allow(non_snake_case, dead_code)]
#vis fn #build_fn_name(self) -> #return_ty
#body
}
}
}
}
impl ToTokens for BuilderWithFields {
fn to_tokens(&self, tokens: &mut TokenStream) {
let Self {
struct_name,
vis,
phantom_type_param,
phantom_type_field,
fields,
} = self;
let span = struct_name.span();
let mut any_generics = Generics::default();
self.append_generics([], true, true, &mut any_generics);
let empty_ty = self.ty([], None, false);
let field_names = Vec::from_iter(fields.iter().map(|v| &v.1.builder_field_name));
let field_type_params = Vec::from_iter(fields.iter().map(|v| &v.1.type_param));
quote_spanned! {span=>
#[allow(non_camel_case_types)]
#[non_exhaustive]
#vis struct #struct_name #any_generics {
#(#field_names: #field_type_params,)*
#phantom_type_field: ::fayalite::__std::marker::PhantomData<#phantom_type_param>,
}
#[automatically_derived]
impl<#phantom_type_param> #empty_ty {
fn new() -> Self {
Self {
#(#field_names: (),)*
#phantom_type_field: ::fayalite::__std::marker::PhantomData,
}
}
}
}
.to_tokens(tokens);
for (field_index, (_, field)) in self.fields.iter().enumerate() {
let initial_fields = &fields[..field_index];
let final_fields = &fields[field_index..][1..];
let initial_type_params =
Vec::from_iter(initial_fields.iter().map(|v| &v.1.type_param));
let final_type_params = Vec::from_iter(final_fields.iter().map(|v| &v.1.type_param));
let initial_field_names =
Vec::from_iter(initial_fields.iter().map(|v| &v.1.builder_field_name));
let final_field_names =
Vec::from_iter(final_fields.iter().map(|v| &v.1.builder_field_name));
let BuilderField {
names: _,
mapped_value,
mapped_type,
where_clause,
builder_field_name,
type_param,
} = field;
quote_spanned! {span=>
#[automatically_derived]
#[allow(non_camel_case_types, dead_code)]
impl<#phantom_type_param #(, #initial_type_params)* #(, #final_type_params)*>
#struct_name<
#phantom_type_param,
#(#initial_type_params,)*
(), #(#final_type_params,)*
>
{
#vis fn #builder_field_name<#type_param>(
self,
#builder_field_name: #type_param,
) -> #struct_name<
#phantom_type_param,
#(#initial_type_params,)*
#mapped_type,
#(#final_type_params,)*
>
#where_clause
{
let Self {
#(#initial_field_names,)*
#builder_field_name: (),
#(#final_field_names,)*
#phantom_type_field: _,
} = self;
let #builder_field_name = #mapped_value;
#struct_name {
#(#field_names,)*
#phantom_type_field: ::fayalite::__std::marker::PhantomData,
}
}
}
}
.to_tokens(tokens);
}
}
}
pub(crate) struct MapIdents {
pub(crate) map: HashMap<Ident, Ident>,
}
impl Fold for &MapIdents {
fn fold_ident(&mut self, i: Ident) -> Ident {
self.map.get(&i).cloned().unwrap_or(i)
}
}
pub(crate) struct DupGenerics<M> {
pub(crate) combined: Generics,
pub(crate) maps: M,
}
pub(crate) fn merge_punctuated<T, P: Default>(
target: &mut Punctuated<T, P>,
source: Punctuated<T, P>,
make_punct: impl FnOnce() -> P,
) {
if source.is_empty() {
return;
}
if target.is_empty() {
*target = source;
return;
}
if !target.trailing_punct() {
target.push_punct(make_punct());
}
target.extend(source.into_pairs());
}
pub(crate) fn merge_generics(target: &mut Generics, source: Generics) {
let Generics {
lt_token,
params,
gt_token,
where_clause,
} = source;
let span = lt_token.map(|v| v.span).unwrap_or_else(|| params.span());
target.lt_token = target.lt_token.or(lt_token);
merge_punctuated(&mut target.params, params, || Token![,](span));
target.gt_token = target.gt_token.or(gt_token);
if let Some(where_clause) = where_clause {
if let Some(target_where_clause) = &mut target.where_clause {
let WhereClause {
where_token,
predicates,
} = where_clause;
let span = where_token.span;
target_where_clause.where_token = where_token;
merge_punctuated(&mut target_where_clause.predicates, predicates, || {
Token![,](span)
});
} else {
target.where_clause = Some(where_clause);
}
}
}
impl DupGenerics<Vec<MapIdents>> {
pub(crate) fn new_dyn(generics: &Generics, count: usize) -> Self {
let mut maps = Vec::from_iter((0..count).map(|_| MapIdents {
map: HashMap::new(),
}));
for param in &generics.params {
let (GenericParam::Lifetime(LifetimeParam {
lifetime: Lifetime { ident, .. },
..
})
| GenericParam::Type(TypeParam { ident, .. })
| GenericParam::Const(ConstParam { ident, .. })) = param;
for (i, map_idents) in maps.iter_mut().enumerate() {
map_idents
.map
.insert(ident.clone(), format_ident!("__{}_{}", ident, i));
}
}
let mut combined = Generics::default();
for map_idents in maps.iter() {
merge_generics(
&mut combined,
fold_generics(&mut { map_idents }, generics.clone()),
);
}
Self { combined, maps }
}
}
impl<const COUNT: usize> DupGenerics<[MapIdents; COUNT]> {
pub(crate) fn new(generics: &Generics) -> Self {
let DupGenerics { combined, maps } = DupGenerics::new_dyn(generics, COUNT);
Self {
combined,
maps: maps.try_into().ok().unwrap(),
}
}
}
pub(crate) fn add_where_predicate(
target: &mut Generics,
span: Span,
where_predicate: WherePredicate,
) {
let WhereClause {
where_token: _,
predicates,
} = target.where_clause.get_or_insert_with(|| WhereClause {
where_token: Token![where](span),
predicates: Punctuated::new(),
});
if !predicates.empty_or_trailing() {
predicates.push_punct(Token![,](span));
}
predicates.push_value(where_predicate);
}
pub(crate) fn make_connect_impl(
connect_inexact: Option<(crate::kw::connect_inexact,)>,
generics: &Generics,
ty_ident: &Ident,
field_types: impl IntoIterator<Item = Type>,
) -> TokenStream {
let span = ty_ident.span();
let impl_generics;
let combined_generics;
let where_clause;
let lhs_generics;
let lhs_type_generics;
let rhs_generics;
let rhs_type_generics;
if connect_inexact.is_some() {
let DupGenerics {
mut combined,
maps: [lhs_map, rhs_map],
} = DupGenerics::new(generics);
for field_type in field_types {
let lhs_type = (&lhs_map).fold_type(field_type.clone());
let rhs_type = (&rhs_map).fold_type(field_type);
add_where_predicate(
&mut combined,
span,
parse_quote_spanned! {span=>
#lhs_type: ::fayalite::ty::Connect<#rhs_type>
},
);
}
combined_generics = combined;
(impl_generics, _, where_clause) = combined_generics.split_for_impl();
lhs_generics = (&lhs_map).fold_generics(generics.clone());
(_, lhs_type_generics, _) = lhs_generics.split_for_impl();
rhs_generics = (&rhs_map).fold_generics(generics.clone());
(_, rhs_type_generics, _) = rhs_generics.split_for_impl();
} else {
let mut generics = generics.clone();
for field_type in field_types {
add_where_predicate(
&mut generics,
span,
parse_quote_spanned! {span=>
#field_type: ::fayalite::ty::Connect<#field_type>
},
);
}
combined_generics = generics;
(impl_generics, lhs_type_generics, where_clause) = combined_generics.split_for_impl();
rhs_type_generics = lhs_type_generics.clone();
}
quote_spanned! {span=>
#[automatically_derived]
#[allow(non_camel_case_types)]
impl #impl_generics ::fayalite::ty::Connect<#ty_ident #rhs_type_generics>
for #ty_ident #lhs_type_generics
#where_clause
{
}
}
}