Skip to content

Clarify push_stream/push_tree #159603

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
rust-bors merged 2 commits into from
Jul 20, 2026
Merged

Clarify push_stream/push_tree #159603

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
203ec33
Avoid unnecessary `push_tree`/`push_stream` usage
nnethercote Jul 20, 2026
693756d
Rename `push_tree`/`push_stream`
nnethercote Jul 20, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
18 changes: 9 additions & 9 deletions compiler/rustc_builtin_macros/src/contracts.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -48,9 +48,9 @@ fn expand_contract_clause(
ecx: &mut ExtCtxt<'_>,
attr_span: Span,
annotated: TokenStream,
inject: impl FnOnce(&mut TokenStream) -> Result<(), ErrorGuaranteed>,
inject: impl FnOnce(&mut Vec<TokenTree>) -> Result<(), ErrorGuaranteed>,
) -> Result<TokenStream, ErrorGuaranteed> {
let mut new_tts = TokenStream::default();
let mut new_tts = vec![];
let mut cursor = annotated.iter();

let is_kw = |tt: &TokenTree, sym: Symbol| {
Expand All @@ -60,7 +60,7 @@ fn expand_contract_clause(
// Find the `fn` keyword to check if this is a function.
if cursor
.find(|tt| {
new_tts.push_tree((*tt).clone());
new_tts.push((*tt).clone());
is_kw(tt, kw::Fn)
})
.is_none()
Expand Down Expand Up @@ -102,7 +102,7 @@ fn expand_contract_clause(
if is_kw(tt, kw::Where) {
break tt;
}
new_tts.push_tree(tt.clone());
new_tts.push(tt.clone());
};

// At this point, we've transcribed everything from the `fn` through the formal parameter list
Expand All @@ -114,9 +114,9 @@ fn expand_contract_clause(

// Above we injected the internal AST requires/ensures construct. Now copy over all the other
// token trees.
new_tts.push_tree(next_tt.clone());
new_tts.push(next_tt.clone());
while let Some(tt) = cursor.next() {
new_tts.push_tree(tt.clone());
new_tts.push(tt.clone());
if cursor.peek().is_none()
&& !matches!(tt, TokenTree::Delimited(_, _, token::Delimiter::Brace, _))
{
Expand All @@ -127,7 +127,7 @@ fn expand_contract_clause(
}
}

Ok(new_tts)
Ok(TokenStream::new(new_tts))
}

fn expand_contract_clause_tts(
Expand All @@ -139,11 +139,11 @@ fn expand_contract_clause_tts(
) -> Result<TokenStream, ErrorGuaranteed> {
let feature_span = ecx.with_def_site_ctxt(attr_span);
expand_contract_clause(ecx, attr_span, annotated, |new_tts| {
new_tts.push_tree(TokenTree::Token(
new_tts.push(TokenTree::Token(
token::Token::from_ast_ident(Ident::new(clause_keyword, feature_span)),
Spacing::Joint,
));
new_tts.push_tree(TokenTree::Delimited(
new_tts.push(TokenTree::Delimited(
DelimSpan::from_single(attr_span),
DelimSpacing::new(Spacing::JointHidden, Spacing::JointHidden),
token::Delimiter::Brace,
Expand Down
9 changes: 6 additions & 3 deletions compiler/rustc_expand/src/mbe/transcribe.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -565,9 +565,12 @@ fn transcribe_pnr<'tx>(

let leading_if_span =
guard.span_with_leading_if.with_hi(guard.span_with_leading_if.lo() + BytePos(2));
let mut ts =
TokenStream::token_alone(token::Ident(kw::If, IdentIsRaw::No), leading_if_span);
ts.push_stream(TokenStream::from_ast(&guard.cond));
let ts = std::iter::once(TokenTree::token_alone(
token::Ident(kw::If, IdentIsRaw::No),
leading_if_span,
))
.chain(TokenStream::from_ast(&guard.cond).iter().cloned())
Comment thread
Kobzol marked this conversation as resolved.
.collect();

mk_delimited(guard.span_with_leading_if, MetaVarKind::Guard, ts)
}
Expand Down