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Apr 30, 2025
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33 changes: 24 additions & 9 deletions compiler/rustc_ast_pretty/src/pprust/state.rs
Original file line number Diff line number Diff line change
@@ -634,6 +634,7 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
false,
None,
*delim,
None,
tokens,
true,
span,
@@ -679,6 +680,7 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
false,
None,
*delim,
Some(spacing.open),
tts,
convert_dollar_crate,
dspan.entire(),
@@ -735,6 +737,7 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
has_bang: bool,
ident: Option<Ident>,
delim: Delimiter,
open_spacing: Option<Spacing>,
tts: &TokenStream,
convert_dollar_crate: bool,
span: Span,
@@ -758,16 +761,26 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
self.nbsp();
}
self.word("{");
if !tts.is_empty() {

// Respect `Alone`, if provided, and print a space. Unless the list is empty.
let open_space = (open_spacing == None || open_spacing == Some(Spacing::Alone))
&& !tts.is_empty();
if open_space {
self.space();
}
let ib = self.ibox(0);
self.print_tts(tts, convert_dollar_crate);
self.end(ib);
let empty = tts.is_empty();
self.bclose(span, empty, cb.unwrap());

// Use `open_space` for the spacing *before* the closing delim.
// Because spacing on delimiters is lost when going through
// proc macros, and otherwise we can end up with ugly cases
// like `{ x}`. Symmetry is better.
self.bclose(span, !open_space, cb.unwrap());
}
delim => {
// `open_spacing` is ignored. We never print spaces after
// non-brace opening delims or before non-brace closing delims.
let token_str = self.token_kind_to_string(&delim.as_open_token_kind());
self.word(token_str);
let ib = self.ibox(0);
@@ -797,6 +810,7 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
has_bang,
Some(*ident),
macro_def.body.delim,
None,
&macro_def.body.tokens,
true,
sp,
@@ -844,9 +858,9 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
self.end(ib);
}

fn bclose_maybe_open(&mut self, span: rustc_span::Span, empty: bool, cb: Option<BoxMarker>) {
fn bclose_maybe_open(&mut self, span: rustc_span::Span, no_space: bool, cb: Option<BoxMarker>) {
let has_comment = self.maybe_print_comment(span.hi());
if !empty || has_comment {
if !no_space || has_comment {
self.break_offset_if_not_bol(1, -INDENT_UNIT);
}
self.word("}");
@@ -855,9 +869,9 @@ pub trait PrintState<'a>: std::ops::Deref<Target = pp::Printer> + std::ops::Dere
}
}

fn bclose(&mut self, span: rustc_span::Span, empty: bool, cb: BoxMarker) {
fn bclose(&mut self, span: rustc_span::Span, no_space: bool, cb: BoxMarker) {
let cb = Some(cb);
self.bclose_maybe_open(span, empty, cb)
self.bclose_maybe_open(span, no_space, cb)
}

fn break_offset_if_not_bol(&mut self, n: usize, off: isize) {
@@ -1423,8 +1437,8 @@ impl<'a> State<'a> {
}
}

let empty = !has_attrs && blk.stmts.is_empty();
self.bclose_maybe_open(blk.span, empty, cb);
let no_space = !has_attrs && blk.stmts.is_empty();
self.bclose_maybe_open(blk.span, no_space, cb);
self.ann.post(self, AnnNode::Block(blk))
}

@@ -1471,6 +1485,7 @@ impl<'a> State<'a> {
true,
None,
m.args.delim,
None,
&m.args.tokens,
true,
m.span(),
4 changes: 2 additions & 2 deletions compiler/rustc_builtin_macros/src/autodiff.rs
Original file line number Diff line number Diff line change
@@ -323,9 +323,9 @@ mod llvm_enzyme {
Spacing::Joint,
)];
let never_arg = ast::DelimArgs {
dspan: ast::tokenstream::DelimSpan::from_single(span),
dspan: DelimSpan::from_single(span),
delim: ast::token::Delimiter::Parenthesis,
tokens: ast::tokenstream::TokenStream::from_iter(ts2),
tokens: TokenStream::from_iter(ts2),
};
let inline_item = ast::AttrItem {
unsafety: ast::Safety::Default,
14 changes: 8 additions & 6 deletions compiler/rustc_expand/src/build.rs
Original file line number Diff line number Diff line change
@@ -1,8 +1,10 @@
use rustc_ast::ptr::P;
use rustc_ast::token::Delimiter;
use rustc_ast::tokenstream::TokenStream;
use rustc_ast::util::literal;
use rustc_ast::{
self as ast, AnonConst, AttrVec, BlockCheckMode, Expr, LocalKind, MatchKind, PatKind, UnOp,
attr, token,
attr, token, tokenstream,
};
use rustc_span::source_map::Spanned;
use rustc_span::{DUMMY_SP, Ident, Span, Symbol, kw, sym};
@@ -55,13 +57,13 @@ impl<'a> ExtCtxt<'a> {
&self,
span: Span,
path: ast::Path,
delim: ast::token::Delimiter,
tokens: ast::tokenstream::TokenStream,
delim: Delimiter,
tokens: TokenStream,
) -> P<ast::MacCall> {
P(ast::MacCall {
path,
args: P(ast::DelimArgs {
dspan: ast::tokenstream::DelimSpan { open: span, close: span },
dspan: tokenstream::DelimSpan { open: span, close: span },
delim,
tokens,
}),
@@ -480,8 +482,8 @@ impl<'a> ExtCtxt<'a> {
span,
[sym::std, sym::unreachable].map(|s| Ident::new(s, span)).to_vec(),
),
ast::token::Delimiter::Parenthesis,
ast::tokenstream::TokenStream::default(),
Delimiter::Parenthesis,
TokenStream::default(),
),
)
}
1 change: 1 addition & 0 deletions compiler/rustc_hir_pretty/src/lib.rs
Original file line number Diff line number Diff line change
@@ -146,6 +146,7 @@ impl<'a> State<'a> {
false,
None,
*delim,
None,
&tokens,
true,
span,
22 changes: 19 additions & 3 deletions tests/ui/macros/stringify.rs
Original file line number Diff line number Diff line change
@@ -288,6 +288,9 @@ fn test_expr() {
// ExprKind::OffsetOf: untestable because this test works pre-expansion.

// ExprKind::MacCall
c1!(expr, [ mac!() ], "mac!()");
c1!(expr, [ mac![] ], "mac![]");
c1!(expr, [ mac! {} ], "mac! {}");
c1!(expr, [ mac!(...) ], "mac!(...)");
c1!(expr, [ mac![...] ], "mac![...]");
c1!(expr, [ mac! { ... } ], "mac! { ... }");
@@ -353,7 +356,8 @@ fn test_item() {
c1!(item, [ pub extern crate self as std; ], "pub extern crate self as std;");

// ItemKind::Use
c1!(item, [ pub use crate::{a, b::c}; ], "pub use crate::{ a, b::c };"); // FIXME
c1!(item, [ pub use crate::{a, b::c}; ], "pub use crate::{a, b::c};");
c1!(item, [ pub use crate::{ e, ff }; ], "pub use crate::{ e, ff };");
c1!(item, [ pub use A::*; ], "pub use A::*;");

// ItemKind::Static
@@ -482,9 +486,12 @@ fn test_item() {
c1!(item, [ impl ~const Struct {} ], "impl ~const Struct {}");

// ItemKind::MacCall
c1!(item, [ mac!(); ], "mac!();");
c1!(item, [ mac![]; ], "mac![];");
c1!(item, [ mac! {} ], "mac! {}");
c1!(item, [ mac!(...); ], "mac!(...);");
c1!(item, [ mac![...]; ], "mac![...];");
c1!(item, [ mac! { ... } ], "mac! { ... }");
c1!(item, [ mac! {...} ], "mac! {...}");

// ItemKind::MacroDef
c1!(item,
@@ -598,8 +605,11 @@ fn test_pat() {
c1!(pat, [ (pat) ], "(pat)");

// PatKind::MacCall
c1!(pat, [ mac!() ], "mac!()");
c1!(pat, [ mac![] ], "mac![]");
c1!(pat, [ mac! {} ], "mac! {}");
c1!(pat, [ mac!(...) ], "mac!(...)");
c1!(pat, [ mac![...] ], "mac![...]");
c1!(pat, [ mac! [ ... ] ], "mac! [...]");
c1!(pat, [ mac! { ... } ], "mac! { ... }");

// Attributes are not allowed on patterns.
@@ -644,6 +654,9 @@ fn test_stmt() {
c1!(stmt, [ ; ], ";");

// StmtKind::MacCall
c1!(stmt, [ mac! ( ) ], "mac! ()");
c1!(stmt, [ mac![] ], "mac![]");
c1!(stmt, [ mac!{} ], "mac!{}");
c1!(stmt, [ mac!(...) ], "mac!(...)");
c1!(stmt, [ mac![...] ], "mac![...]");
c1!(stmt, [ mac! { ... } ], "mac! { ... }");
@@ -739,6 +752,9 @@ fn test_ty() {
// TyKind::ImplicitSelf: there is no syntax for this.

// TyKind::MacCall
c1!(ty, [ mac!() ], "mac!()");
c1!(ty, [ mac![] ], "mac![]");
c1!(ty, [ mac! { } ], "mac! {}");
c1!(ty, [ mac!(...) ], "mac!(...)");
c1!(ty, [ mac![...] ], "mac![...]");
c1!(ty, [ mac! { ... } ], "mac! { ... }");
6 changes: 3 additions & 3 deletions tests/ui/macros/trace_faulty_macros.stderr
Original file line number Diff line number Diff line change
@@ -87,9 +87,9 @@ LL | let a = pat_macro!();
| ^^^^^^^^^^^^
|
= note: expanding `pat_macro! { }`
= note: to `pat_macro! (A { a : a, b : 0, c : _, .. });`
= note: expanding `pat_macro! { A { a : a, b : 0, c : _, .. } }`
= note: to `A { a : a, b : 0, c : _, .. }`
= note: to `pat_macro! (A {a : a, b : 0, c : _, ..});`
= note: expanding `pat_macro! { A {a : a, b : 0, c : _, ..} }`
= note: to `A {a : a, b : 0, c : _, ..}`

note: trace_macro
--> $DIR/trace_faulty_macros.rs:53:5
2 changes: 1 addition & 1 deletion tests/ui/proc-macro/attr-complex-fn.stdout
Original file line number Diff line number Diff line change
@@ -77,7 +77,7 @@ PRINT-ATTR INPUT (DEBUG): TokenStream [
span: $DIR/attr-complex-fn.rs:19:42: 19:44 (#0),
},
]
PRINT-ATTR INPUT (DISPLAY): impl<T> MyTrait<T> for MyStruct<{ true }> { #![rustc_dummy] }
PRINT-ATTR INPUT (DISPLAY): impl<T> MyTrait<T> for MyStruct<{true}> { #![rustc_dummy] }
PRINT-ATTR RE-COLLECTED (DISPLAY): impl < T > MyTrait < T > for MyStruct < { true } > { #![rustc_dummy] }
PRINT-ATTR DEEP-RE-COLLECTED (DISPLAY): impl < T > MyTrait < T > for MyStruct < { true } > { #! [rustc_dummy] }
PRINT-ATTR INPUT (DEBUG): TokenStream [
9 changes: 4 additions & 5 deletions tests/ui/proc-macro/weird-braces.stdout
Original file line number Diff line number Diff line change
@@ -5,7 +5,7 @@ PRINT-ATTR_ARGS INPUT (DEBUG): TokenStream [
span: $DIR/weird-braces.rs:16:25: 16:36 (#0),
},
]
PRINT-ATTR INPUT (DISPLAY): #[print_target_and_args(second_outer)] impl Bar<{ 1 > 0 }> for Foo<{ true }>
PRINT-ATTR INPUT (DISPLAY): #[print_target_and_args(second_outer)] impl Bar<{1 > 0}> for Foo<{true}>
{
#![print_target_and_args(first_inner)]
#![print_target_and_args(second_inner)]
@@ -191,7 +191,7 @@ PRINT-ATTR_ARGS INPUT (DEBUG): TokenStream [
span: $DIR/weird-braces.rs:17:25: 17:37 (#0),
},
]
PRINT-ATTR INPUT (DISPLAY): impl Bar<{ 1 > 0 }> for Foo<{ true }>
PRINT-ATTR INPUT (DISPLAY): impl Bar<{1 > 0}> for Foo<{true}>
{
#![print_target_and_args(first_inner)]
#![print_target_and_args(second_inner)]
@@ -350,8 +350,7 @@ PRINT-ATTR_ARGS INPUT (DEBUG): TokenStream [
span: $DIR/weird-braces.rs:19:30: 19:41 (#0),
},
]
PRINT-ATTR INPUT (DISPLAY): impl Bar<{ 1 > 0 }> for Foo<{ true }>
{ #![print_target_and_args(second_inner)] }
PRINT-ATTR INPUT (DISPLAY): impl Bar<{1 > 0}> for Foo<{true}> { #![print_target_and_args(second_inner)] }
PRINT-ATTR RE-COLLECTED (DISPLAY): impl Bar < { 1 > 0 } > for Foo < { true } >
{ #![print_target_and_args(second_inner)] }
PRINT-ATTR DEEP-RE-COLLECTED (DISPLAY): impl Bar < { 1 > 0 } > for Foo < { true } >
@@ -470,7 +469,7 @@ PRINT-ATTR_ARGS INPUT (DEBUG): TokenStream [
span: $DIR/weird-braces.rs:20:30: 20:42 (#0),
},
]
PRINT-ATTR INPUT (DISPLAY): impl Bar<{ 1 > 0 }> for Foo<{ true }> {}
PRINT-ATTR INPUT (DISPLAY): impl Bar<{1 > 0}> for Foo<{true}> {}
PRINT-ATTR RE-COLLECTED (DISPLAY): impl Bar < { 1 > 0 } > for Foo < { true } > {}
PRINT-ATTR INPUT (DEBUG): TokenStream [
Ident {
2 changes: 1 addition & 1 deletion tests/ui/unpretty/expanded-exhaustive.stdout
Original file line number Diff line number Diff line change
@@ -505,7 +505,7 @@ mod items {
mod item_mac_call { }
/// ItemKind::MacroDef
mod item_macro_def {
macro_rules! mac { () => { ... }; }
macro_rules! mac { () => {...}; }
pub macro stringify { () => {} }
}
/// ItemKind::Delegation