| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/pin-project-internal-1.1.0/src/utils.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>utils.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../pin_project_internal/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../pin_project_internal/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span>std::{iter::FromIterator, mem}; |
| |
| <span class="kw">use </span>proc_macro2::{Group, Spacing, Span, TokenStream, TokenTree}; |
| <span class="kw">use </span>quote::{quote, quote_spanned, ToTokens}; |
| <span class="kw">use </span>syn::{ |
| parse::{Parse, ParseBuffer, ParseStream}, |
| parse_quote, |
| punctuated::Punctuated, |
| token, |
| visit_mut::{<span class="self">self</span>, VisitMut}, |
| Attribute, ExprPath, ExprStruct, Generics, Ident, Item, Lifetime, LifetimeParam, Macro, |
| PatStruct, PatTupleStruct, Path, PathArguments, PredicateType, QSelf, <span class="prelude-ty">Result</span>, Token, Type, |
| TypeParamBound, TypePath, Variant, Visibility, WherePredicate, |
| }; |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">type </span>Variants = Punctuated<Variant, <span class="macro">Token!</span>[,]>; |
| |
| <span class="macro">macro_rules! </span>format_err { |
| (<span class="macro-nonterminal">$span</span>:expr, <span class="macro-nonterminal">$msg</span>:expr $(,)<span class="question-mark">?</span>) => { |
| syn::Error::new_spanned(<span class="kw-2">&</span><span class="macro-nonterminal">$span </span><span class="kw">as </span><span class="kw-2">&</span><span class="kw">dyn </span>quote::ToTokens, <span class="kw-2">&</span><span class="macro-nonterminal">$msg </span><span class="kw">as </span><span class="kw-2">&</span><span class="kw">dyn </span>std::fmt::Display) |
| }; |
| (<span class="macro-nonterminal">$span</span>:expr, $(<span class="macro-nonterminal">$tt</span>:tt)<span class="kw-2">*</span>) => { |
| <span class="macro">format_err!</span>(<span class="macro-nonterminal">$span</span>, <span class="macro">format!</span>($(<span class="macro-nonterminal">$tt</span>)<span class="kw-2">*</span>)) |
| }; |
| } |
| |
| <span class="macro">macro_rules! </span>bail { |
| ($(<span class="macro-nonterminal">$tt</span>:tt)<span class="kw-2">*</span>) => { |
| <span class="kw">return </span><span class="prelude-val">Err</span>(<span class="macro">format_err!</span>($(<span class="macro-nonterminal">$tt</span>)<span class="kw-2">*</span>)) |
| }; |
| } |
| |
| <span class="macro">macro_rules! </span>parse_quote_spanned { |
| (<span class="macro-nonterminal">$span</span>:expr => $(<span class="macro-nonterminal">$tt</span>:tt)<span class="kw-2">*</span>) => { |
| syn::parse2(<span class="macro">quote::quote_spanned!</span>(<span class="macro-nonterminal">$span </span>=> $(<span class="macro-nonterminal">$tt</span>)<span class="kw-2">*</span>)).unwrap_or_else(|e| <span class="macro">panic!</span>(<span class="string">"{}"</span>, e)) |
| }; |
| } |
| |
| <span class="doccomment">/// Determines the lifetime names. Ensure it doesn't overlap with any existing |
| /// lifetime names. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>determine_lifetime_name(lifetime_name: <span class="kw-2">&mut </span>String, generics: <span class="kw-2">&mut </span>Generics) { |
| <span class="kw">struct </span>CollectLifetimes(Vec<String>); |
| |
| <span class="kw">impl </span>VisitMut <span class="kw">for </span>CollectLifetimes { |
| <span class="kw">fn </span>visit_lifetime_param_mut(<span class="kw-2">&mut </span><span class="self">self</span>, def: <span class="kw-2">&mut </span>LifetimeParam) { |
| <span class="self">self</span>.<span class="number">0</span>.push(def.lifetime.to_string()); |
| } |
| } |
| |
| <span class="macro">debug_assert!</span>(lifetime_name.starts_with(<span class="string">'\''</span>)); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>lifetimes = CollectLifetimes(Vec::new()); |
| lifetimes.visit_generics_mut(generics); |
| |
| <span class="kw">while </span>lifetimes.<span class="number">0</span>.iter().any(|name| name.starts_with(<span class="kw-2">&**</span>lifetime_name)) { |
| lifetime_name.push(<span class="string">'_'</span>); |
| } |
| } |
| |
| <span class="doccomment">/// Like `insert_lifetime`, but also generates a bound of the form |
| /// `OriginalType<A, B>: 'lifetime`. Used when generating the definition |
| /// of a projection type |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>insert_lifetime_and_bound( |
| generics: <span class="kw-2">&mut </span>Generics, |
| lifetime: Lifetime, |
| orig_generics: <span class="kw-2">&</span>Generics, |
| orig_ident: <span class="kw-2">&</span>Ident, |
| ) -> WherePredicate { |
| insert_lifetime(generics, lifetime.clone()); |
| |
| <span class="kw">let </span>orig_type: Type = <span class="macro">parse_quote!</span>(#orig_ident #orig_generics); |
| <span class="kw">let </span><span class="kw-2">mut </span>punct = Punctuated::new(); |
| punct.push(TypeParamBound::Lifetime(lifetime)); |
| |
| WherePredicate::Type(PredicateType { |
| lifetimes: <span class="prelude-val">None</span>, |
| bounded_ty: orig_type, |
| colon_token: <<span class="macro">Token!</span>[:]>::default(), |
| bounds: punct, |
| }) |
| } |
| |
| <span class="doccomment">/// Inserts a `lifetime` at position `0` of `generics.params`. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>insert_lifetime(generics: <span class="kw-2">&mut </span>Generics, lifetime: Lifetime) { |
| generics.lt_token.get_or_insert_with(<<span class="macro">Token!</span>[<]>::default); |
| generics.gt_token.get_or_insert_with(<<span class="macro">Token!</span>[>]>::default); |
| generics.params.insert(<span class="number">0</span>, LifetimeParam::new(lifetime).into()); |
| } |
| |
| <span class="doccomment">/// Determines the visibility of the projected types and projection methods. |
| /// |
| /// If given visibility is `pub`, returned visibility is `pub(crate)`. |
| /// Otherwise, returned visibility is the same as given visibility. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>determine_visibility(vis: <span class="kw-2">&</span>Visibility) -> Visibility { |
| <span class="kw">if let </span>Visibility::Public(token) = vis { |
| <span class="macro">parse_quote_spanned!</span>(token.span => <span class="kw">pub</span>(<span class="kw">crate</span>)) |
| } <span class="kw">else </span>{ |
| vis.clone() |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>respan<T>(node: <span class="kw-2">&</span>T, span: Span) -> T |
| <span class="kw">where |
| </span>T: ToTokens + Parse, |
| { |
| <span class="kw">let </span>tokens = node.to_token_stream(); |
| <span class="kw">let </span>respanned = respan_tokens(tokens, span); |
| syn::parse2(respanned).unwrap() |
| } |
| |
| <span class="kw">fn </span>respan_tokens(tokens: TokenStream, span: Span) -> TokenStream { |
| tokens |
| .into_iter() |
| .map(|<span class="kw-2">mut </span>token| { |
| token.set_span(span); |
| token |
| }) |
| .collect() |
| } |
| |
| <span class="comment">// ================================================================================================= |
| // extension traits |
| |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">trait </span>SliceExt { |
| <span class="kw">fn </span>position_exact(<span class="kw-2">&</span><span class="self">self</span>, ident: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><usize>>; |
| <span class="kw">fn </span>find(<span class="kw-2">&</span><span class="self">self</span>, ident: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span>Attribute>; |
| } |
| |
| <span class="kw">impl </span>SliceExt <span class="kw">for </span>[Attribute] { |
| <span class="doccomment">/// # Errors |
| /// |
| /// - There are multiple specified attributes. |
| /// - The `Attribute::tokens` field of the specified attribute is not empty. |
| </span><span class="kw">fn </span>position_exact(<span class="kw-2">&</span><span class="self">self</span>, ident: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><usize>> { |
| <span class="self">self</span>.iter() |
| .try_fold((<span class="number">0</span>, <span class="prelude-val">None</span>), |(i, <span class="kw-2">mut </span>prev), attr| { |
| <span class="kw">if </span>attr.path().is_ident(ident) { |
| <span class="kw">if </span>prev.replace(i).is_some() { |
| <span class="macro">bail!</span>(attr, <span class="string">"duplicate #[{}] attribute"</span>, ident); |
| } |
| attr.meta.require_path_only()<span class="question-mark">?</span>; |
| } |
| <span class="prelude-val">Ok</span>((i + <span class="number">1</span>, prev)) |
| }) |
| .map(|(<span class="kw">_</span>, pos)| pos) |
| } |
| |
| <span class="kw">fn </span>find(<span class="kw-2">&</span><span class="self">self</span>, ident: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span>Attribute> { |
| <span class="self">self</span>.iter().position(|attr| attr.path().is_ident(ident)).map(|i| <span class="kw-2">&</span><span class="self">self</span>[i]) |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">trait </span>ParseBufferExt<<span class="lifetime">'a</span>> { |
| <span class="kw">fn </span>parenthesized(<span class="self">self</span>) -> <span class="prelude-ty">Result</span><ParseBuffer<<span class="lifetime">'a</span>>>; |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>> ParseBufferExt<<span class="lifetime">'a</span>> <span class="kw">for </span>ParseStream<<span class="lifetime">'a</span>> { |
| <span class="kw">fn </span>parenthesized(<span class="self">self</span>) -> <span class="prelude-ty">Result</span><ParseBuffer<<span class="lifetime">'a</span>>> { |
| <span class="kw">let </span>content; |
| <span class="kw">let _</span>: token::Paren = <span class="macro">syn::parenthesized!</span>(content <span class="kw">in </span><span class="self">self</span>); |
| <span class="prelude-val">Ok</span>(content) |
| } |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>> ParseBufferExt<<span class="lifetime">'a</span>> <span class="kw">for </span>ParseBuffer<<span class="lifetime">'a</span>> { |
| <span class="kw">fn </span>parenthesized(<span class="self">self</span>) -> <span class="prelude-ty">Result</span><ParseBuffer<<span class="lifetime">'a</span>>> { |
| <span class="kw">let </span>content; |
| <span class="kw">let _</span>: token::Paren = <span class="macro">syn::parenthesized!</span>(content <span class="kw">in </span><span class="self">self</span>); |
| <span class="prelude-val">Ok</span>(content) |
| } |
| } |
| |
| <span class="comment">// ================================================================================================= |
| // visitors |
| |
| // Replace `self`/`Self` with `__self`/`self_ty`. |
| // Based on: |
| // - https://github.com/dtolnay/async-trait/blob/0.1.35/src/receiver.rs |
| // - https://github.com/dtolnay/async-trait/commit/6029cbf375c562ca98fa5748e9d950a8ff93b0e7 |
| |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>ReplaceReceiver<<span class="lifetime">'a</span>>(<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw-2">&</span><span class="lifetime">'a </span>TypePath); |
| |
| <span class="kw">impl </span>ReplaceReceiver<<span class="lifetime">'_</span>> { |
| <span class="kw">fn </span>self_ty(<span class="kw-2">&</span><span class="self">self</span>, span: Span) -> TypePath { |
| respan(<span class="self">self</span>.<span class="number">0</span>, span) |
| } |
| |
| <span class="kw">fn </span>self_to_qself(<span class="kw-2">&</span><span class="self">self</span>, qself: <span class="kw-2">&mut </span><span class="prelude-ty">Option</span><QSelf>, path: <span class="kw-2">&mut </span>Path) { |
| <span class="kw">if </span>path.leading_colon.is_some() { |
| <span class="kw">return</span>; |
| } |
| |
| <span class="kw">let </span>first = <span class="kw-2">&</span>path.segments[<span class="number">0</span>]; |
| <span class="kw">if </span>first.ident != <span class="string">"Self" </span>|| !first.arguments.is_empty() { |
| <span class="kw">return</span>; |
| } |
| |
| <span class="kw">if </span>path.segments.len() == <span class="number">1 </span>{ |
| <span class="self">self</span>.self_to_expr_path(path); |
| <span class="kw">return</span>; |
| } |
| |
| <span class="kw">let </span>span = first.ident.span(); |
| <span class="kw-2">*</span>qself = <span class="prelude-val">Some</span>(QSelf { |
| lt_token: <span class="macro">Token!</span>[<](span), |
| ty: Box::new(<span class="self">self</span>.self_ty(span).into()), |
| position: <span class="number">0</span>, |
| as_token: <span class="prelude-val">None</span>, |
| gt_token: <span class="macro">Token!</span>[>](span), |
| }); |
| |
| path.leading_colon = <span class="prelude-val">Some</span>(<span class="kw-2">**</span>path.segments.pairs().next().unwrap().punct().unwrap()); |
| |
| <span class="kw">let </span>segments = mem::replace(<span class="kw-2">&mut </span>path.segments, Punctuated::new()); |
| path.segments = segments.into_pairs().skip(<span class="number">1</span>).collect(); |
| } |
| |
| <span class="kw">fn </span>self_to_expr_path(<span class="kw-2">&</span><span class="self">self</span>, path: <span class="kw-2">&mut </span>Path) { |
| <span class="kw">if </span>path.leading_colon.is_some() { |
| <span class="kw">return</span>; |
| } |
| |
| <span class="kw">let </span>first = <span class="kw-2">&</span>path.segments[<span class="number">0</span>]; |
| <span class="kw">if </span>first.ident != <span class="string">"Self" </span>|| !first.arguments.is_empty() { |
| <span class="kw">return</span>; |
| } |
| |
| <span class="kw">let </span>self_ty = <span class="self">self</span>.self_ty(first.ident.span()); |
| <span class="kw">let </span>variant = mem::replace(path, self_ty.path); |
| <span class="kw">for </span>segment <span class="kw">in </span><span class="kw-2">&mut </span>path.segments { |
| <span class="kw">if let </span>PathArguments::AngleBracketed(bracketed) = <span class="kw-2">&mut </span>segment.arguments { |
| <span class="kw">if </span>bracketed.colon2_token.is_none() && !bracketed.args.is_empty() { |
| bracketed.colon2_token = <span class="prelude-val">Some</span>(<<span class="macro">Token!</span>[::]>::default()); |
| } |
| } |
| } |
| <span class="kw">if </span>variant.segments.len() > <span class="number">1 </span>{ |
| path.segments.push_punct(<<span class="macro">Token!</span>[::]>::default()); |
| path.segments.extend(variant.segments.into_pairs().skip(<span class="number">1</span>)); |
| } |
| } |
| |
| <span class="kw">fn </span>visit_token_stream(<span class="kw-2">&</span><span class="self">self</span>, tokens: <span class="kw-2">&mut </span>TokenStream) -> bool { |
| <span class="kw">let </span><span class="kw-2">mut </span>out = Vec::new(); |
| <span class="kw">let </span><span class="kw-2">mut </span>modified = <span class="bool-val">false</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>iter = tokens.clone().into_iter().peekable(); |
| <span class="kw">while let </span><span class="prelude-val">Some</span>(tt) = iter.next() { |
| <span class="kw">match </span>tt { |
| TokenTree::Ident(<span class="kw-2">mut </span>ident) => { |
| modified |= prepend_underscore_to_self(<span class="kw-2">&mut </span>ident); |
| <span class="kw">if </span>ident == <span class="string">"Self" </span>{ |
| modified = <span class="bool-val">true</span>; |
| <span class="kw">let </span>self_ty = <span class="self">self</span>.self_ty(ident.span()); |
| <span class="kw">match </span>iter.peek() { |
| <span class="prelude-val">Some</span>(TokenTree::Punct(p)) |
| <span class="kw">if </span>p.as_char() == <span class="string">':' </span>&& p.spacing() == Spacing::Joint => |
| { |
| <span class="kw">let </span>next = iter.next().unwrap(); |
| <span class="kw">match </span>iter.peek() { |
| <span class="prelude-val">Some</span>(TokenTree::Punct(p)) <span class="kw">if </span>p.as_char() == <span class="string">':' </span>=> { |
| <span class="kw">let </span>span = ident.span(); |
| out.extend(<span class="macro">quote_spanned!</span>(span=> <#self_ty>)); |
| } |
| <span class="kw">_ </span>=> out.extend(<span class="macro">quote!</span>(#self_ty)), |
| } |
| out.push(next); |
| } |
| <span class="kw">_ </span>=> out.extend(<span class="macro">quote!</span>(#self_ty)), |
| } |
| } <span class="kw">else </span>{ |
| out.push(TokenTree::Ident(ident)); |
| } |
| } |
| TokenTree::Group(group) => { |
| <span class="kw">let </span><span class="kw-2">mut </span>content = group.stream(); |
| modified |= <span class="self">self</span>.visit_token_stream(<span class="kw-2">&mut </span>content); |
| <span class="kw">let </span><span class="kw-2">mut </span>new = Group::new(group.delimiter(), content); |
| new.set_span(group.span()); |
| out.push(TokenTree::Group(new)); |
| } |
| other => out.push(other), |
| } |
| } |
| <span class="kw">if </span>modified { |
| <span class="kw-2">*</span>tokens = TokenStream::from_iter(out); |
| } |
| modified |
| } |
| } |
| |
| <span class="kw">impl </span>VisitMut <span class="kw">for </span>ReplaceReceiver<<span class="lifetime">'_</span>> { |
| <span class="comment">// `Self` -> `Receiver` |
| </span><span class="kw">fn </span>visit_type_mut(<span class="kw-2">&mut </span><span class="self">self</span>, ty: <span class="kw-2">&mut </span>Type) { |
| <span class="kw">if let </span>Type::Path(node) = ty { |
| <span class="kw">if </span>node.qself.is_none() && node.path.is_ident(<span class="string">"Self"</span>) { |
| <span class="kw-2">*</span>ty = <span class="self">self</span>.self_ty(node.path.segments[<span class="number">0</span>].ident.span()).into(); |
| } <span class="kw">else </span>{ |
| <span class="self">self</span>.visit_type_path_mut(node); |
| } |
| } <span class="kw">else </span>{ |
| visit_mut::visit_type_mut(<span class="self">self</span>, ty); |
| } |
| } |
| |
| <span class="comment">// `Self::Assoc` -> `<Receiver>::Assoc` |
| </span><span class="kw">fn </span>visit_type_path_mut(<span class="kw-2">&mut </span><span class="self">self</span>, ty: <span class="kw-2">&mut </span>TypePath) { |
| <span class="kw">if </span>ty.qself.is_none() { |
| <span class="self">self</span>.self_to_qself(<span class="kw-2">&mut </span>ty.qself, <span class="kw-2">&mut </span>ty.path); |
| } |
| visit_mut::visit_type_path_mut(<span class="self">self</span>, ty); |
| } |
| |
| <span class="comment">// `Self::method` -> `<Receiver>::method` |
| </span><span class="kw">fn </span>visit_expr_path_mut(<span class="kw-2">&mut </span><span class="self">self</span>, expr: <span class="kw-2">&mut </span>ExprPath) { |
| <span class="kw">if </span>expr.qself.is_none() { |
| <span class="self">self</span>.self_to_qself(<span class="kw-2">&mut </span>expr.qself, <span class="kw-2">&mut </span>expr.path); |
| } |
| visit_mut::visit_expr_path_mut(<span class="self">self</span>, expr); |
| } |
| |
| <span class="kw">fn </span>visit_expr_struct_mut(<span class="kw-2">&mut </span><span class="self">self</span>, expr: <span class="kw-2">&mut </span>ExprStruct) { |
| <span class="self">self</span>.self_to_expr_path(<span class="kw-2">&mut </span>expr.path); |
| visit_mut::visit_expr_struct_mut(<span class="self">self</span>, expr); |
| } |
| |
| <span class="kw">fn </span>visit_pat_struct_mut(<span class="kw-2">&mut </span><span class="self">self</span>, pat: <span class="kw-2">&mut </span>PatStruct) { |
| <span class="self">self</span>.self_to_expr_path(<span class="kw-2">&mut </span>pat.path); |
| visit_mut::visit_pat_struct_mut(<span class="self">self</span>, pat); |
| } |
| |
| <span class="kw">fn </span>visit_pat_tuple_struct_mut(<span class="kw-2">&mut </span><span class="self">self</span>, pat: <span class="kw-2">&mut </span>PatTupleStruct) { |
| <span class="self">self</span>.self_to_expr_path(<span class="kw-2">&mut </span>pat.path); |
| visit_mut::visit_pat_tuple_struct_mut(<span class="self">self</span>, pat); |
| } |
| |
| <span class="kw">fn </span>visit_path_mut(<span class="kw-2">&mut </span><span class="self">self</span>, path: <span class="kw-2">&mut </span>Path) { |
| <span class="kw">if </span>path.segments.len() == <span class="number">1 </span>{ |
| <span class="comment">// Replace `self`, but not `self::function`. |
| </span>prepend_underscore_to_self(<span class="kw-2">&mut </span>path.segments[<span class="number">0</span>].ident); |
| } |
| <span class="kw">for </span>segment <span class="kw">in </span><span class="kw-2">&mut </span>path.segments { |
| <span class="self">self</span>.visit_path_arguments_mut(<span class="kw-2">&mut </span>segment.arguments); |
| } |
| } |
| |
| <span class="kw">fn </span>visit_item_mut(<span class="kw-2">&mut </span><span class="self">self</span>, item: <span class="kw-2">&mut </span>Item) { |
| <span class="kw">match </span>item { |
| <span class="comment">// Visit `macro_rules!` because locally defined macros can refer to `self`. |
| </span>Item::Macro(item) <span class="kw">if </span>item.mac.path.is_ident(<span class="string">"macro_rules"</span>) => { |
| <span class="self">self</span>.visit_macro_mut(<span class="kw-2">&mut </span>item.mac); |
| } |
| <span class="comment">// Otherwise, do not recurse into nested items. |
| </span><span class="kw">_ </span>=> {} |
| } |
| } |
| |
| <span class="kw">fn </span>visit_macro_mut(<span class="kw-2">&mut </span><span class="self">self</span>, mac: <span class="kw-2">&mut </span>Macro) { |
| <span class="comment">// We can't tell in general whether `self` inside a macro invocation |
| // refers to the self in the argument list or a different self |
| // introduced within the macro. Heuristic: if the macro input contains |
| // `fn`, then `self` is more likely to refer to something other than the |
| // outer function's self argument. |
| </span><span class="kw">if </span>!contains_fn(mac.tokens.clone()) { |
| <span class="self">self</span>.visit_token_stream(<span class="kw-2">&mut </span>mac.tokens); |
| } |
| } |
| } |
| |
| <span class="kw">fn </span>contains_fn(tokens: TokenStream) -> bool { |
| tokens.into_iter().any(|tt| <span class="kw">match </span>tt { |
| TokenTree::Ident(ident) => ident == <span class="string">"fn"</span>, |
| TokenTree::Group(group) => contains_fn(group.stream()), |
| <span class="kw">_ </span>=> <span class="bool-val">false</span>, |
| }) |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>prepend_underscore_to_self(ident: <span class="kw-2">&mut </span>Ident) -> bool { |
| <span class="kw">let </span>modified = ident == <span class="string">"self"</span>; |
| <span class="kw">if </span>modified { |
| <span class="kw-2">*</span>ident = Ident::new(<span class="string">"__self"</span>, ident.span()); |
| } |
| modified |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="pin_project_internal" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
