Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 502 insertions, 0 deletions

diff --git a/third_party/rust/async-trait/src/expand.rs b/third_party/rust/async-trait/src/expand.rs
new file mode 100644
index 0000000000..88338db9bc
--- /dev/null
+++ b/third_party/rust/async-trait/src/expand.rs
@@ -0,0 +1,502 @@
+use crate::bound::{has_bound, InferredBound, Supertraits};
+use crate::lifetime::{AddLifetimeToImplTrait, CollectLifetimes};
+use crate::parse::Item;
+use crate::receiver::{has_self_in_block, has_self_in_sig, mut_pat, ReplaceSelf};
+use proc_macro2::{Span, TokenStream};
+use quote::{format_ident, quote, quote_spanned, ToTokens};
+use std::collections::BTreeSet as Set;
+use std::mem;
+use syn::punctuated::Punctuated;
+use syn::visit_mut::{self, VisitMut};
+use syn::{
+    parse_quote, parse_quote_spanned, Attribute, Block, FnArg, GenericArgument, GenericParam,
+    Generics, Ident, ImplItem, Lifetime, LifetimeDef, Pat, PatIdent, PathArguments, Receiver,
+    ReturnType, Signature, Stmt, Token, TraitItem, Type, TypePath, WhereClause,
+};
+
+impl ToTokens for Item {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        match self {
+            Item::Trait(item) => item.to_tokens(tokens),
+            Item::Impl(item) => item.to_tokens(tokens),
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+enum Context<'a> {
+    Trait {
+        generics: &'a Generics,
+        supertraits: &'a Supertraits,
+    },
+    Impl {
+        impl_generics: &'a Generics,
+        associated_type_impl_traits: &'a Set<Ident>,
+    },
+}
+
+impl Context<'_> {
+    fn lifetimes<'a>(&'a self, used: &'a [Lifetime]) -> impl Iterator<Item = &'a LifetimeDef> {
+        let generics = match self {
+            Context::Trait { generics, .. } => generics,
+            Context::Impl { impl_generics, .. } => impl_generics,
+        };
+        generics.params.iter().filter_map(move |param| {
+            if let GenericParam::Lifetime(param) = param {
+                if used.contains(&param.lifetime) {
+                    return Some(param);
+                }
+            }
+            None
+        })
+    }
+}
+
+pub fn expand(input: &mut Item, is_local: bool) {
+    match input {
+        Item::Trait(input) => {
+            let context = Context::Trait {
+                generics: &input.generics,
+                supertraits: &input.supertraits,
+            };
+            for inner in &mut input.items {
+                if let TraitItem::Method(method) = inner {
+                    let sig = &mut method.sig;
+                    if sig.asyncness.is_some() {
+                        let block = &mut method.default;
+                        let mut has_self = has_self_in_sig(sig);
+                        method.attrs.push(parse_quote!(#[must_use]));
+                        if let Some(block) = block {
+                            has_self |= has_self_in_block(block);
+                            transform_block(context, sig, block);
+                            method.attrs.push(lint_suppress_with_body());
+                        } else {
+                            method.attrs.push(lint_suppress_without_body());
+                        }
+                        let has_default = method.default.is_some();
+                        transform_sig(context, sig, has_self, has_default, is_local);
+                    }
+                }
+            }
+        }
+        Item::Impl(input) => {
+            let mut lifetimes = CollectLifetimes::new("'impl");
+            lifetimes.visit_type_mut(&mut *input.self_ty);
+            lifetimes.visit_path_mut(&mut input.trait_.as_mut().unwrap().1);
+            let params = &input.generics.params;
+            let elided = lifetimes.elided;
+            input.generics.params = parse_quote!(#(#elided,)* #params);
+
+            let mut associated_type_impl_traits = Set::new();
+            for inner in &input.items {
+                if let ImplItem::Type(assoc) = inner {
+                    if let Type::ImplTrait(_) = assoc.ty {
+                        associated_type_impl_traits.insert(assoc.ident.clone());
+                    }
+                }
+            }
+
+            let context = Context::Impl {
+                impl_generics: &input.generics,
+                associated_type_impl_traits: &associated_type_impl_traits,
+            };
+            for inner in &mut input.items {
+                if let ImplItem::Method(method) = inner {
+                    let sig = &mut method.sig;
+                    if sig.asyncness.is_some() {
+                        let block = &mut method.block;
+                        let has_self = has_self_in_sig(sig) || has_self_in_block(block);
+                        transform_block(context, sig, block);
+                        transform_sig(context, sig, has_self, false, is_local);
+                        method.attrs.push(lint_suppress_with_body());
+                    }
+                }
+            }
+        }
+    }
+}
+
+fn lint_suppress_with_body() -> Attribute {
+    parse_quote! {
+        #[allow(
+            clippy::async_yields_async,
+            clippy::let_unit_value,
+            clippy::no_effect_underscore_binding,
+            clippy::shadow_same,
+            clippy::type_complexity,
+            clippy::type_repetition_in_bounds,
+            clippy::used_underscore_binding
+        )]
+    }
+}
+
+fn lint_suppress_without_body() -> Attribute {
+    parse_quote! {
+        #[allow(
+            clippy::type_complexity,
+            clippy::type_repetition_in_bounds
+        )]
+    }
+}
+
+// Input:
+//     async fn f<T>(&self, x: &T) -> Ret;
+//
+// Output:
+//     fn f<'life0, 'life1, 'async_trait, T>(
+//         &'life0 self,
+//         x: &'life1 T,
+//     ) -> Pin<Box<dyn Future<Output = Ret> + Send + 'async_trait>>
+//     where
+//         'life0: 'async_trait,
+//         'life1: 'async_trait,
+//         T: 'async_trait,
+//         Self: Sync + 'async_trait;
+fn transform_sig(
+    context: Context,
+    sig: &mut Signature,
+    has_self: bool,
+    has_default: bool,
+    is_local: bool,
+) {
+    let default_span = sig.asyncness.take().unwrap().span;
+    sig.fn_token.span = default_span;
+
+    let (ret_arrow, ret) = match &sig.output {
+        ReturnType::Default => (Token![->](default_span), quote_spanned!(default_span=> ())),
+        ReturnType::Type(arrow, ret) => (*arrow, quote!(#ret)),
+    };
+
+    let mut lifetimes = CollectLifetimes::new("'life");
+    for arg in sig.inputs.iter_mut() {
+        match arg {
+            FnArg::Receiver(arg) => lifetimes.visit_receiver_mut(arg),
+            FnArg::Typed(arg) => lifetimes.visit_type_mut(&mut arg.ty),
+        }
+    }
+
+    for param in &mut sig.generics.params {
+        match param {
+            GenericParam::Type(param) => {
+                let param_name = &param.ident;
+                let span = match param.colon_token.take() {
+                    Some(colon_token) => colon_token.span,
+                    None => param_name.span(),
+                };
+                let bounds = mem::replace(&mut param.bounds, Punctuated::new());
+                where_clause_or_default(&mut sig.generics.where_clause)
+                    .predicates
+                    .push(parse_quote_spanned!(span=> #param_name: 'async_trait + #bounds));
+            }
+            GenericParam::Lifetime(param) => {
+                let param_name = &param.lifetime;
+                let span = match param.colon_token.take() {
+                    Some(colon_token) => colon_token.span,
+                    None => param_name.span(),
+                };
+                let bounds = mem::replace(&mut param.bounds, Punctuated::new());
+                where_clause_or_default(&mut sig.generics.where_clause)
+                    .predicates
+                    .push(parse_quote_spanned!(span=> #param: 'async_trait + #bounds));
+            }
+            GenericParam::Const(_) => {}
+        }
+    }
+
+    for param in context.lifetimes(&lifetimes.explicit) {
+        let param = &param.lifetime;
+        let span = param.span();
+        where_clause_or_default(&mut sig.generics.where_clause)
+            .predicates
+            .push(parse_quote_spanned!(span=> #param: 'async_trait));
+    }
+
+    if sig.generics.lt_token.is_none() {
+        sig.generics.lt_token = Some(Token![<](sig.ident.span()));
+    }
+    if sig.generics.gt_token.is_none() {
+        sig.generics.gt_token = Some(Token![>](sig.paren_token.span));
+    }
+
+    for elided in lifetimes.elided {
+        sig.generics.params.push(parse_quote!(#elided));
+        where_clause_or_default(&mut sig.generics.where_clause)
+            .predicates
+            .push(parse_quote_spanned!(elided.span()=> #elided: 'async_trait));
+    }
+
+    sig.generics
+        .params
+        .push(parse_quote_spanned!(default_span=> 'async_trait));
+
+    if has_self {
+        let bounds: &[InferredBound] = match sig.inputs.iter().next() {
+            Some(FnArg::Receiver(Receiver {
+                reference: Some(_),
+                mutability: None,
+                ..
+            })) => &[InferredBound::Sync],
+            Some(FnArg::Typed(arg))
+                if match arg.pat.as_ref() {
+                    Pat::Ident(pat) => pat.ident == "self",
+                    _ => false,
+                } =>
+            {
+                match arg.ty.as_ref() {
+                    // self: &Self
+                    Type::Reference(ty) if ty.mutability.is_none() => &[InferredBound::Sync],
+                    // self: Arc<Self>
+                    Type::Path(ty)
+                        if {
+                            let segment = ty.path.segments.last().unwrap();
+                            segment.ident == "Arc"
+                                && match &segment.arguments {
+                                    PathArguments::AngleBracketed(arguments) => {
+                                        arguments.args.len() == 1
+                                            && match &arguments.args[0] {
+                                                GenericArgument::Type(Type::Path(arg)) => {
+                                                    arg.path.is_ident("Self")
+                                                }
+                                                _ => false,
+                                            }
+                                    }
+                                    _ => false,
+                                }
+                        } =>
+                    {
+                        &[InferredBound::Sync, InferredBound::Send]
+                    }
+                    _ => &[InferredBound::Send],
+                }
+            }
+            _ => &[InferredBound::Send],
+        };
+
+        let bounds = bounds.iter().filter_map(|bound| {
+            let assume_bound = match context {
+                Context::Trait { supertraits, .. } => !has_default || has_bound(supertraits, bound),
+                Context::Impl { .. } => true,
+            };
+            if assume_bound || is_local {
+                None
+            } else {
+                Some(bound.spanned_path(default_span))
+            }
+        });
+
+        where_clause_or_default(&mut sig.generics.where_clause)
+            .predicates
+            .push(parse_quote_spanned! {default_span=>
+                Self: #(#bounds +)* 'async_trait
+            });
+    }
+
+    for (i, arg) in sig.inputs.iter_mut().enumerate() {
+        match arg {
+            FnArg::Receiver(Receiver {
+                reference: Some(_), ..
+            }) => {}
+            FnArg::Receiver(arg) => arg.mutability = None,
+            FnArg::Typed(arg) => {
+                let type_is_reference = match *arg.ty {
+                    Type::Reference(_) => true,
+                    _ => false,
+                };
+                if let Pat::Ident(pat) = &mut *arg.pat {
+                    if pat.ident == "self" || !type_is_reference {
+                        pat.by_ref = None;
+                        pat.mutability = None;
+                    }
+                } else if !type_is_reference {
+                    let positional = positional_arg(i, &arg.pat);
+                    let m = mut_pat(&mut arg.pat);
+                    arg.pat = parse_quote!(#m #positional);
+                }
+                AddLifetimeToImplTrait.visit_type_mut(&mut arg.ty);
+            }
+        }
+    }
+
+    let bounds = if is_local {
+        quote_spanned!(default_span=> 'async_trait)
+    } else {
+        quote_spanned!(default_span=> ::core::marker::Send + 'async_trait)
+    };
+    sig.output = parse_quote_spanned! {default_span=>
+        #ret_arrow ::core::pin::Pin<Box<
+            dyn ::core::future::Future<Output = #ret> + #bounds
+        >>
+    };
+}
+
+// Input:
+//     async fn f<T>(&self, x: &T, (a, b): (A, B)) -> Ret {
+//         self + x + a + b
+//     }
+//
+// Output:
+//     Box::pin(async move {
+//         let ___ret: Ret = {
+//             let __self = self;
+//             let x = x;
+//             let (a, b) = __arg1;
+//
+//             __self + x + a + b
+//         };
+//
+//         ___ret
+//     })
+fn transform_block(context: Context, sig: &mut Signature, block: &mut Block) {
+    if let Some(Stmt::Item(syn::Item::Verbatim(item))) = block.stmts.first() {
+        if block.stmts.len() == 1 && item.to_string() == ";" {
+            return;
+        }
+    }
+
+    let mut self_span = None;
+    let decls = sig
+        .inputs
+        .iter()
+        .enumerate()
+        .map(|(i, arg)| match arg {
+            FnArg::Receiver(Receiver {
+                self_token,
+                mutability,
+                ..
+            }) => {
+                let ident = Ident::new("__self", self_token.span);
+                self_span = Some(self_token.span);
+                quote!(let #mutability #ident = #self_token;)
+            }
+            FnArg::Typed(arg) => {
+                // If there is a #[cfg(...)] attribute that selectively enables
+                // the parameter, forward it to the variable.
+                //
+                // This is currently not applied to the `self` parameter.
+                let attrs = arg.attrs.iter().filter(|attr| attr.path.is_ident("cfg"));
+
+                if let Pat::Ident(PatIdent {
+                    ident, mutability, ..
+                }) = &*arg.pat
+                {
+                    if ident == "self" {
+                        self_span = Some(ident.span());
+                        let prefixed = Ident::new("__self", ident.span());
+                        quote!(let #mutability #prefixed = #ident;)
+                    } else if let Type::Reference(_) = *arg.ty {
+                        quote!()
+                    } else {
+                        quote! {
+                            #(#attrs)*
+                            let #mutability #ident = #ident;
+                        }
+                    }
+                } else if let Type::Reference(_) = *arg.ty {
+                    quote!()
+                } else {
+                    let pat = &arg.pat;
+                    let ident = positional_arg(i, pat);
+                    if let Pat::Wild(_) = **pat {
+                        quote! {
+                            #(#attrs)*
+                            let #ident = #ident;
+                        }
+                    } else {
+                        quote! {
+                            #(#attrs)*
+                            let #pat = {
+                                let #ident = #ident;
+                                #ident
+                            };
+                        }
+                    }
+                }
+            }
+        })
+        .collect::<Vec<_>>();
+
+    if let Some(span) = self_span {
+        let mut replace_self = ReplaceSelf(span);
+        replace_self.visit_block_mut(block);
+    }
+
+    let stmts = &block.stmts;
+    let let_ret = match &mut sig.output {
+        ReturnType::Default => quote_spanned! {block.brace_token.span=>
+            #(#decls)*
+            let _: () = { #(#stmts)* };
+        },
+        ReturnType::Type(_, ret) => {
+            if contains_associated_type_impl_trait(context, ret) {
+                if decls.is_empty() {
+                    quote!(#(#stmts)*)
+                } else {
+                    quote!(#(#decls)* { #(#stmts)* })
+                }
+            } else {
+                quote_spanned! {block.brace_token.span=>
+                    if let ::core::option::Option::Some(__ret) = ::core::option::Option::None::<#ret> {
+                        return __ret;
+                    }
+                    #(#decls)*
+                    let __ret: #ret = { #(#stmts)* };
+                    #[allow(unreachable_code)]
+                    __ret
+                }
+            }
+        }
+    };
+    let box_pin = quote_spanned!(block.brace_token.span=>
+        Box::pin(async move { #let_ret })
+    );
+    block.stmts = parse_quote!(#box_pin);
+}
+
+fn positional_arg(i: usize, pat: &Pat) -> Ident {
+    let span: Span = syn::spanned::Spanned::span(pat);
+    #[cfg(not(no_span_mixed_site))]
+    let span = span.resolved_at(Span::mixed_site());
+    format_ident!("__arg{}", i, span = span)
+}
+
+fn contains_associated_type_impl_trait(context: Context, ret: &mut Type) -> bool {
+    struct AssociatedTypeImplTraits<'a> {
+        set: &'a Set<Ident>,
+        contains: bool,
+    }
+
+    impl<'a> VisitMut for AssociatedTypeImplTraits<'a> {
+        fn visit_type_path_mut(&mut self, ty: &mut TypePath) {
+            if ty.qself.is_none()
+                && ty.path.segments.len() == 2
+                && ty.path.segments[0].ident == "Self"
+                && self.set.contains(&ty.path.segments[1].ident)
+            {
+                self.contains = true;
+            }
+            visit_mut::visit_type_path_mut(self, ty);
+        }
+    }
+
+    match context {
+        Context::Trait { .. } => false,
+        Context::Impl {
+            associated_type_impl_traits,
+            ..
+        } => {
+            let mut visit = AssociatedTypeImplTraits {
+                set: associated_type_impl_traits,
+                contains: false,
+            };
+            visit.visit_type_mut(ret);
+            visit.contains
+        }
+    }
+}
+
+fn where_clause_or_default(clause: &mut Option<WhereClause>) -> &mut WhereClause {
+    clause.get_or_insert_with(|| WhereClause {
+        where_token: Default::default(),
+        predicates: Punctuated::new(),
+    })
+}