Use correct edition when parsing :pat matchers

compiler/rustc_expand/src/mbe/macro_rules.rs

@@ -467,6 +467,7 @@ pub fn compile_declarative_macro(
  &sess.parse_sess,
  def.id,
  features,
+ edition,
  )
  .pop()
  .unwrap();
@@ -492,6 +493,7 @@ pub fn compile_declarative_macro(
  &sess.parse_sess,
  def.id,
  features,
+ edition,
  )
  .pop()
  .unwrap();

compiler/rustc_expand/src/mbe/quoted.rs

@@ -9,7 +9,8 @@ use rustc_feature::Features;
 use rustc_session::parse::ParseSess;
 use rustc_span::symbol::{kw, Ident};
 
-use rustc_span::Span;
+use rustc_span::edition::Edition;
+use rustc_span::{Span, SyntaxContext};
 
 use rustc_data_structures::sync::Lrc;
 
@@ -32,6 +33,7 @@ const VALID_FRAGMENT_NAMES_MSG: &str = "valid fragment specifiers are \
 /// - `sess`: the parsing session. Any errors will be emitted to this session.
 /// - `node_id`: the NodeId of the macro we are parsing.
 /// - `features`: language features so we can do feature gating.
+/// - `edition`: the edition of the crate defining the macro
 ///
 /// # Returns
 ///
@@ -42,6 +44,7 @@ pub(super) fn parse(
  sess: &ParseSess,
  node_id: NodeId,
  features: &Features,
+ edition: Edition,
 ) -> Vec<TokenTree> {
  // Will contain the final collection of `self::TokenTree`
  let mut result = Vec::new();
@@ -52,7 +55,7 @@ pub(super) fn parse(
  while let Some(tree) = trees.next() {
  // Given the parsed tree, if there is a metavar and we are expecting matchers, actually
  // parse out the matcher (i.e., in `$id:ident` this would parse the `:` and `ident`).
- let tree = parse_tree(tree, &mut trees, expect_matchers, sess, node_id, features);
+ let tree = parse_tree(tree, &mut trees, expect_matchers, sess, node_id, features, edition);
  match tree {
  TokenTree::MetaVar(start_sp, ident) if expect_matchers => {
  let span = match trees.next() {
@@ -64,7 +67,19 @@ pub(super) fn parse(
 
  let kind =
  token::NonterminalKind::from_symbol(frag.name, || {
- span.edition()
+ // FIXME(#85708) - once we properly decode a foreign
+ // crate's `SyntaxContext::root`, then we can replace
+ // this with just `span.edition()`. A
+ // `SyntaxContext::root()` from the current crate will
+ // have the edition of the current crate, and a
+ // `SyntaxxContext::root()` from a foreign crate will
+ // have the edition of that crate (which we manually
+ // retrieve via the `edition` parameter).
+ if span.ctxt() == SyntaxContext::root() {
+ edition
+ } else {
+ span.edition()
+ }
  })
  .unwrap_or_else(
  || {
@@ -117,13 +132,15 @@ pub(super) fn parse(
 /// - `expect_matchers`: same as for `parse` (see above).
 /// - `sess`: the parsing session. Any errors will be emitted to this session.
 /// - `features`: language features so we can do feature gating.
+/// - `edition` - the edition of the crate defining the macro
 fn parse_tree(
  tree: tokenstream::TokenTree,
  outer_trees: &mut impl Iterator<Item = tokenstream::TokenTree>,
  expect_matchers: bool,
  sess: &ParseSess,
  node_id: NodeId,
  features: &Features,
+ edition: Edition,
 ) -> TokenTree {
  // Depending on what `tree` is, we could be parsing different parts of a macro
  match tree {
@@ -151,7 +168,7 @@ fn parse_tree(
  sess.span_diagnostic.span_err(span.entire(), &msg);
  }
  // Parse the contents of the sequence itself
- let sequence = parse(tts, expect_matchers, sess, node_id, features);
+ let sequence = parse(tts, expect_matchers, sess, node_id, features, edition);
  // Get the Kleene operator and optional separator
  let (separator, kleene) =
  parse_sep_and_kleene_op(&mut trees, span.entire(), sess);
@@ -204,7 +221,7 @@ fn parse_tree(
  span,
  Lrc::new(Delimited {
  delim,
- tts: parse(tts, expect_matchers, sess, node_id, features),
+ tts: parse(tts, expect_matchers, sess, node_id, features, edition),
  }),
  ),
  }

src/test/ui/macros/auxiliary/foreign-crate-macro-pat.rs

@@ -0,0 +1,11 @@
+// edition:2018
+
+#[macro_export]
+macro_rules! custom_matches {
+ ($expression:expr, $( $pattern:pat )|+ $( if $guard: expr )? $(,)?) => {
+ match $expression {
+ $( $pattern )|+ $( if $guard )? => true,
+ _ => false
+ }
+ }
+}

src/test/ui/macros/cross-crate-pat-span.rs

@@ -0,0 +1,12 @@
+// edition:2021
+// check-pass
+// aux-build: foreign-crate-macro-pat.rs
+//
+// Tests that the edition of the foreign crate is used
+// when determining the behavior of the `:pat` matcher.
+
+extern crate foreign_crate_macro_pat;
+
+fn main() {
+ let _b = foreign_crate_macro_pat::custom_matches!(b'3', b'0' ..= b'9');
+}

src/test/ui/macros/issue-84429-matches-edition.rs

@@ -0,0 +1,9 @@
+// edition:2021
+// check-pass
+//
+// Regression test for issue #84429
+// Tests that we can properly invoke `matches!` from a 2021-edition crate.
+
+fn main() {
+ let _b = matches!(b'3', b'0' ..= b'9');
+}