From f5a2bb6263ad332ceb2d9b3b82afe935259a7723 Mon Sep 17 00:00:00 2001 From: "Andrew V. Teylu" Date: Mon, 2 Mar 2026 20:28:16 +0000 Subject: [PATCH 1/2] Add hygiene annotations for tokens in macro_rules! bodies MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit `-Zunpretty=expanded,hygiene` was not printing syntax context annotations for identifiers and lifetimes inside `macro_rules!` bodies. These tokens are printed via `print_tt()` → `token_to_string_ext()`, which converts tokens to strings without calling `ann_post()`. This meant that macro-generated `macro_rules!` definitions with hygienic metavar parameters (e.g. multiple `$marg` distinguished only by hygiene) were printed with no way to tell them apart. This was fixed by adding a match on `token.kind` in `print_tt()` to call `ann_post()` for `Ident`, `NtIdent`, `Lifetime`, and `NtLifetime` tokens, matching how `print_ident()` and `print_lifetime()` already handle AST-level identifiers and lifetimes. Signed-off-by: Andrew V. Teylu --- compiler/rustc_ast_pretty/src/pprust/state.rs | 17 ++++++ .../hygiene/unpretty-debug-lifetimes.stdout | 8 +-- tests/ui/hygiene/unpretty-debug-metavars.rs | 25 +++++++++ .../ui/hygiene/unpretty-debug-metavars.stdout | 52 +++++++++++++++++++ tests/ui/hygiene/unpretty-debug.stdout | 10 +++- tests/ui/proc-macro/meta-macro-hygiene.stdout | 5 +- .../nonterminal-token-hygiene.stdout | 17 ++++-- 7 files changed, 122 insertions(+), 12 deletions(-) create mode 100644 tests/ui/hygiene/unpretty-debug-metavars.rs create mode 100644 tests/ui/hygiene/unpretty-debug-metavars.stdout diff --git a/compiler/rustc_ast_pretty/src/pprust/state.rs b/compiler/rustc_ast_pretty/src/pprust/state.rs index f4168301bc5d..7d963dd2037c 100644 --- a/compiler/rustc_ast_pretty/src/pprust/state.rs +++ b/compiler/rustc_ast_pretty/src/pprust/state.rs @@ -735,6 +735,23 @@ fn print_tt(&mut self, tt: &TokenTree, convert_dollar_crate: bool) -> Spacing { TokenTree::Token(token, spacing) => { let token_str = self.token_to_string_ext(token, convert_dollar_crate); self.word(token_str); + // Emit hygiene annotations for identity-bearing tokens, + // matching how print_ident() and print_lifetime() call ann_post(). + match token.kind { + token::Ident(name, _) => { + self.ann_post(Ident::new(name, token.span)); + } + token::NtIdent(ident, _) => { + self.ann_post(ident); + } + token::Lifetime(name, _) => { + self.ann_post(Ident::new(name, token.span)); + } + token::NtLifetime(ident, _) => { + self.ann_post(ident); + } + _ => {} + } if let token::DocComment(..) = token.kind { self.hardbreak() } diff --git a/tests/ui/hygiene/unpretty-debug-lifetimes.stdout b/tests/ui/hygiene/unpretty-debug-lifetimes.stdout index 28a5c70a02d7..689453326c0b 100644 --- a/tests/ui/hygiene/unpretty-debug-lifetimes.stdout +++ b/tests/ui/hygiene/unpretty-debug-lifetimes.stdout @@ -7,15 +7,17 @@ // Don't break whenever Symbol numbering changes //@ normalize-stdout: "\d+#" -> "0#" -#![feature /* 0#0 */(decl_macro)] -#![feature /* 0#0 */(no_core)] +#![feature /* 0#0 */(decl_macro /* 0#0 */)] +#![feature /* 0#0 */(no_core /* 0#0 */)] #![no_core /* 0#0 */] macro lifetime_hygiene /* 0#0 */ { - ($f:ident<$a:lifetime>) => { fn $f<$a, 'a>() {} } + ($f /* 0#0 */:ident /* 0#0 */<$a /* 0#0 */:lifetime /* 0#0 */>) + => + { fn /* 0#0 */ $f /* 0#0 */<$a /* 0#0 */, 'a /* 0#0 */>() {} } } fn f /* 0#0 */<'a /* 0#0 */, 'a /* 0#1 */>() {} diff --git a/tests/ui/hygiene/unpretty-debug-metavars.rs b/tests/ui/hygiene/unpretty-debug-metavars.rs new file mode 100644 index 000000000000..a0c47bec3ccf --- /dev/null +++ b/tests/ui/hygiene/unpretty-debug-metavars.rs @@ -0,0 +1,25 @@ +//@ check-pass +//@ compile-flags: -Zunpretty=expanded,hygiene + +// Regression test: metavar parameters in macro-generated macro_rules! +// definitions should have hygiene annotations so that textually identical +// `$marg` bindings are distinguishable by their syntax contexts. + +// Don't break whenever Symbol numbering changes +//@ normalize-stdout: "\d+#" -> "0#" + +#![feature(no_core)] +#![no_core] + +macro_rules! make_macro { + (@inner $name:ident ($dol:tt) $a:ident) => { + macro_rules! $name { + ($dol $a : expr, $dol marg : expr) => {} + } + }; + ($name:ident) => { + make_macro!{@inner $name ($) marg} + }; +} + +make_macro!(add2); diff --git a/tests/ui/hygiene/unpretty-debug-metavars.stdout b/tests/ui/hygiene/unpretty-debug-metavars.stdout new file mode 100644 index 000000000000..307c5e1b8de9 --- /dev/null +++ b/tests/ui/hygiene/unpretty-debug-metavars.stdout @@ -0,0 +1,52 @@ +//@ check-pass +//@ compile-flags: -Zunpretty=expanded,hygiene + +// Regression test: metavar parameters in macro-generated macro_rules! +// definitions should have hygiene annotations so that textually identical +// `$marg` bindings are distinguishable by their syntax contexts. + +// Don't break whenever Symbol numbering changes +//@ normalize-stdout: "\d+#" -> "0#" + +#![feature /* 0#0 */(no_core /* 0#0 */)] +#![no_core /* 0#0 */] + +macro_rules! make_macro + /* + 0#0 + */ { + (@inner /* 0#0 */ $name /* 0#0 */:ident /* 0#0 + */($dol /* 0#0 */:tt /* 0#0 */) $a /* 0#0 */:ident /* 0#0 */) + => + { + macro_rules /* 0#0 */! $name /* 0#0 */ + { + ($dol /* 0#0 */ $a /* 0#0 */ : expr /* 0#0 */, $dol /* + 0#0 */ marg /* 0#0 */ : expr /* 0#0 */) => {} + } + }; ($name /* 0#0 */:ident /* 0#0 */) => + { + make_macro /* 0#0 + */!{@inner /* 0#0 */ $name /* 0#0 */($) marg /* 0#0 */} + }; +} +macro_rules! add2 + /* + 0#0 + */ { + ($ marg /* 0#1 */ : expr /* 0#2 */, $marg /* 0#2 */ : expr /* + 0#2 */) => {} +} + + +/* +Expansions: +crate0::{{expn0}}: parent: crate0::{{expn0}}, call_site_ctxt: #0, def_site_ctxt: #0, kind: Root +crate0::{{expn1}}: parent: crate0::{{expn0}}, call_site_ctxt: #0, def_site_ctxt: #0, kind: Macro(Bang, "make_macro") +crate0::{{expn2}}: parent: crate0::{{expn1}}, call_site_ctxt: #1, def_site_ctxt: #0, kind: Macro(Bang, "make_macro") + +SyntaxContexts: +#0: parent: #0, outer_mark: (crate0::{{expn0}}, Opaque) +#1: parent: #0, outer_mark: (crate0::{{expn1}}, SemiOpaque) +#2: parent: #0, outer_mark: (crate0::{{expn2}}, SemiOpaque) +*/ diff --git a/tests/ui/hygiene/unpretty-debug.stdout b/tests/ui/hygiene/unpretty-debug.stdout index f35bd7a7cb2c..ac6051e2d542 100644 --- a/tests/ui/hygiene/unpretty-debug.stdout +++ b/tests/ui/hygiene/unpretty-debug.stdout @@ -5,10 +5,16 @@ //@ normalize-stdout: "\d+#" -> "0#" // minimal junk -#![feature /* 0#0 */(no_core)] +#![feature /* 0#0 */(no_core /* 0#0 */)] #![no_core /* 0#0 */] -macro_rules! foo /* 0#0 */ { ($x: ident) => { y + $x } } +macro_rules! foo + /* + 0#0 + */ { + ($x /* 0#0 */: ident /* 0#0 */) => + { y /* 0#0 */ + $x /* 0#0 */ } +} fn bar /* 0#0 */() { let x /* 0#0 */ = 1; diff --git a/tests/ui/proc-macro/meta-macro-hygiene.stdout b/tests/ui/proc-macro/meta-macro-hygiene.stdout index b5db9922b31a..a03e567bd48a 100644 --- a/tests/ui/proc-macro/meta-macro-hygiene.stdout +++ b/tests/ui/proc-macro/meta-macro-hygiene.stdout @@ -1,7 +1,7 @@ Def site: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) Input: TokenStream [Ident { ident: "$crate", span: $DIR/meta-macro-hygiene.rs:26:37: 26:43 (#3) }, Punct { ch: ':', spacing: Joint, span: $DIR/meta-macro-hygiene.rs:26:43: 26:44 (#3) }, Punct { ch: ':', spacing: Alone, span: $DIR/meta-macro-hygiene.rs:26:44: 26:45 (#3) }, Ident { ident: "dummy", span: $DIR/meta-macro-hygiene.rs:26:45: 26:50 (#3) }, Punct { ch: '!', spacing: Alone, span: $DIR/meta-macro-hygiene.rs:26:50: 26:51 (#3) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: $DIR/meta-macro-hygiene.rs:26:51: 26:53 (#3) }] Respanned: TokenStream [Ident { ident: "$crate", span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }, Punct { ch: ':', spacing: Joint, span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }, Punct { ch: ':', spacing: Alone, span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }, Ident { ident: "dummy", span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }, Punct { ch: '!', spacing: Alone, span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }, Group { delimiter: Parenthesis, stream: TokenStream [], span: $DIR/auxiliary/make-macro.rs:7:9: 7:56 (#4) }] -#![feature /* 0#0 */(prelude_import)] +#![feature /* 0#0 */(prelude_import /* 0#0 */)] //@ aux-build:make-macro.rs //@ proc-macro: meta-macro.rs //@ edition:2018 @@ -30,7 +30,8 @@ macro_rules! produce_it */ { () => { - meta_macro::print_def_site!($crate::dummy!()); + meta_macro /* 0#0 */::print_def_site /* 0#0 + */!($crate /* 0#0 */::dummy /* 0#0 */!()); // `print_def_site!` will respan the `$crate` identifier // with `Span::def_site()`. This should cause it to resolve // relative to `meta_macro`, *not* `make_macro` (despite diff --git a/tests/ui/proc-macro/nonterminal-token-hygiene.stdout b/tests/ui/proc-macro/nonterminal-token-hygiene.stdout index e45abab03b4c..61b55782e6e9 100644 --- a/tests/ui/proc-macro/nonterminal-token-hygiene.stdout +++ b/tests/ui/proc-macro/nonterminal-token-hygiene.stdout @@ -20,7 +20,7 @@ PRINT-BANG INPUT (DEBUG): TokenStream [ span: $DIR/nonterminal-token-hygiene.rs:23:27: 23:32 (#4), }, ] -#![feature /* 0#0 */(prelude_import)] +#![feature /* 0#0 */(prelude_import /* 0#0 */)] #![no_std /* 0#0 */] // Make sure that marks from declarative macros are applied to tokens in nonterminal. @@ -34,7 +34,7 @@ PRINT-BANG INPUT (DEBUG): TokenStream [ //@ proc-macro: test-macros.rs //@ edition: 2015 -#![feature /* 0#0 */(decl_macro)] +#![feature /* 0#0 */(decl_macro /* 0#0 */)] #![no_std /* 0#0 */] extern crate core /* 0#2 */; #[prelude_import /* 0#1 */] @@ -49,15 +49,22 @@ macro_rules! outer /* 0#0 */ { - ($item:item) => + ($item /* 0#0 */:item /* 0#0 */) => { - macro inner() { print_bang! { $item } } inner!(); + macro /* 0#0 */ inner /* 0#0 */() + { print_bang /* 0#0 */! { $item /* 0#0 */ } } inner /* 0#0 + */!(); }; } struct S /* 0#0 */; -macro inner /* 0#3 */ { () => { print_bang! { struct S; } } } +macro inner + /* + 0#3 + */ { + () => { print_bang /* 0#3 */! { struct /* 0#0 */ S /* 0#0 */; } } +} struct S /* 0#5 */; // OK, not a duplicate definition of `S` From bf6db4f345799e1f922b3109a7278d8be11f3058 Mon Sep 17 00:00:00 2001 From: "Andrew V. Teylu" Date: Tue, 3 Mar 2026 13:06:55 +0000 Subject: [PATCH 2/2] Add regression tests for token hygiene annotations in macro bodies Add `unpretty-debug-shadow` test covering macro body tokens that reference a shadowed variable, and simplify the `unpretty-debug-metavars` test macro. Signed-off-by: Andrew V. Teylu --- tests/ui/hygiene/unpretty-debug-metavars.rs | 7 +++-- .../ui/hygiene/unpretty-debug-metavars.stdout | 7 +++-- tests/ui/hygiene/unpretty-debug-shadow.rs | 20 +++++++++++++ tests/ui/hygiene/unpretty-debug-shadow.stdout | 30 +++++++++++++++++++ 4 files changed, 58 insertions(+), 6 deletions(-) create mode 100644 tests/ui/hygiene/unpretty-debug-shadow.rs create mode 100644 tests/ui/hygiene/unpretty-debug-shadow.stdout diff --git a/tests/ui/hygiene/unpretty-debug-metavars.rs b/tests/ui/hygiene/unpretty-debug-metavars.rs index a0c47bec3ccf..41bf75cd0d98 100644 --- a/tests/ui/hygiene/unpretty-debug-metavars.rs +++ b/tests/ui/hygiene/unpretty-debug-metavars.rs @@ -1,9 +1,10 @@ //@ check-pass //@ compile-flags: -Zunpretty=expanded,hygiene -// Regression test: metavar parameters in macro-generated macro_rules! -// definitions should have hygiene annotations so that textually identical -// `$marg` bindings are distinguishable by their syntax contexts. +// Regression test for token hygiene annotations in -Zunpretty=expanded,hygiene +// Previously, metavar parameters in macro-generated macro_rules! definitions +// were missing hygiene annotations, making identical `$marg` bindings +// indistinguishable. // Don't break whenever Symbol numbering changes //@ normalize-stdout: "\d+#" -> "0#" diff --git a/tests/ui/hygiene/unpretty-debug-metavars.stdout b/tests/ui/hygiene/unpretty-debug-metavars.stdout index 307c5e1b8de9..89658bc909a1 100644 --- a/tests/ui/hygiene/unpretty-debug-metavars.stdout +++ b/tests/ui/hygiene/unpretty-debug-metavars.stdout @@ -1,9 +1,10 @@ //@ check-pass //@ compile-flags: -Zunpretty=expanded,hygiene -// Regression test: metavar parameters in macro-generated macro_rules! -// definitions should have hygiene annotations so that textually identical -// `$marg` bindings are distinguishable by their syntax contexts. +// Regression test for token hygiene annotations in -Zunpretty=expanded,hygiene +// Previously, metavar parameters in macro-generated macro_rules! definitions +// were missing hygiene annotations, making identical `$marg` bindings +// indistinguishable. // Don't break whenever Symbol numbering changes //@ normalize-stdout: "\d+#" -> "0#" diff --git a/tests/ui/hygiene/unpretty-debug-shadow.rs b/tests/ui/hygiene/unpretty-debug-shadow.rs new file mode 100644 index 000000000000..2aa68c8aec11 --- /dev/null +++ b/tests/ui/hygiene/unpretty-debug-shadow.rs @@ -0,0 +1,20 @@ +//@ check-pass +//@ compile-flags: -Zunpretty=expanded,hygiene + +// Regression test for token hygiene annotations in -Zunpretty=expanded,hygiene +// Previously, tokens in macro_rules! bodies were missing hygiene annotations, +// making it impossible to see how a macro's reference to a shadowed variable +// is distinguished from the shadowing binding. + +// Don't break whenever Symbol numbering changes +//@ normalize-stdout: "\d+#" -> "0#" + +#![feature(no_core)] +#![no_core] + +fn f() { + let x = 0; + macro_rules! use_x { () => { x }; } + let x = 1; + use_x!(); +} diff --git a/tests/ui/hygiene/unpretty-debug-shadow.stdout b/tests/ui/hygiene/unpretty-debug-shadow.stdout new file mode 100644 index 000000000000..36076b6a968f --- /dev/null +++ b/tests/ui/hygiene/unpretty-debug-shadow.stdout @@ -0,0 +1,30 @@ +//@ check-pass +//@ compile-flags: -Zunpretty=expanded,hygiene + +// Regression test for token hygiene annotations in -Zunpretty=expanded,hygiene +// Previously, tokens in macro_rules! bodies were missing hygiene annotations, +// making it impossible to see how a macro's reference to a shadowed variable +// is distinguished from the shadowing binding. + +// Don't break whenever Symbol numbering changes +//@ normalize-stdout: "\d+#" -> "0#" + +#![feature /* 0#0 */(no_core /* 0#0 */)] +#![no_core /* 0#0 */] + +fn f /* 0#0 */() { + let x /* 0#0 */ = 0; + macro_rules! use_x /* 0#0 */ { () => { x /* 0#0 */ }; } + let x /* 0#0 */ = 1; + x /* 0#1 */; +} + +/* +Expansions: +crate0::{{expn0}}: parent: crate0::{{expn0}}, call_site_ctxt: #0, def_site_ctxt: #0, kind: Root +crate0::{{expn1}}: parent: crate0::{{expn0}}, call_site_ctxt: #0, def_site_ctxt: #0, kind: Macro(Bang, "use_x") + +SyntaxContexts: +#0: parent: #0, outer_mark: (crate0::{{expn0}}, Opaque) +#1: parent: #0, outer_mark: (crate0::{{expn1}}, SemiOpaque) +*/