1 files changed, 154 insertions, 0 deletions
diff --git a/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/mbe/meta_syntax.rs b/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/mbe/meta_syntax.rs
new file mode 100644
index 000000000..8aff78408
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/hir-def/src/macro_expansion_tests/mbe/meta_syntax.rs
@@ -0,0 +1,154 @@
+//! Test for the syntax of macros themselves.
+
+use expect_test::expect;
+
+use crate::macro_expansion_tests::check;
+
+#[test]
+fn well_formed_macro_rules() {
+    check(
+        r#"
+macro_rules! m {
+    ($i:ident) => ();
+    ($(x),*) => ();
+    ($(x)_*) => ();
+    ($(x)i*) => ();
+    ($($i:ident)*) => ($_);
+    ($($true:ident)*) => ($true);
+    ($($false:ident)*) => ($false);
+    (double_dollar) => ($$);
+    ($) => (m!($););
+    ($($t:tt)*) => ($( ${ignore(t)} ${index()} )-*);
+}
+m!($);
+"#,
+        expect![[r#"
+macro_rules! m {
+    ($i:ident) => ();
+    ($(x),*) => ();
+    ($(x)_*) => ();
+    ($(x)i*) => ();
+    ($($i:ident)*) => ($_);
+    ($($true:ident)*) => ($true);
+    ($($false:ident)*) => ($false);
+    (double_dollar) => ($$);
+    ($) => (m!($););
+    ($($t:tt)*) => ($( ${ignore(t)} ${index()} )-*);
+}
+m!($);
+"#]],
+    )
+}
+
+#[test]
+fn malformed_macro_rules() {
+    check(
+        r#"
+macro_rules! i1 { invalid }
+i1!();
+
+macro_rules! e1 { $i:ident => () }
+e1!();
+macro_rules! e2 { ($i:ident) () }
+e2!();
+macro_rules! e3 { ($(i:ident)_) => () }
+e3!();
+
+macro_rules! f1 { ($i) => ($i) }
+f1!();
+macro_rules! f2 { ($i:) => ($i) }
+f2!();
+macro_rules! f3 { ($i:_) => () }
+f3!();
+
+macro_rules! m1 { ($$i) => () }
+m1!();
+macro_rules! m2 { () => ( ${invalid()} ) }
+m2!();
+"#,
+        expect![[r#"
+macro_rules! i1 { invalid }
+/* error: invalid macro definition: expected subtree */
+
+macro_rules! e1 { $i:ident => () }
+/* error: invalid macro definition: expected subtree */
+macro_rules! e2 { ($i:ident) () }
+/* error: invalid macro definition: expected `=` */
+macro_rules! e3 { ($(i:ident)_) => () }
+/* error: invalid macro definition: invalid repeat */
+
+macro_rules! f1 { ($i) => ($i) }
+/* error: invalid macro definition: missing fragment specifier */
+macro_rules! f2 { ($i:) => ($i) }
+/* error: invalid macro definition: missing fragment specifier */
+macro_rules! f3 { ($i:_) => () }
+/* error: invalid macro definition: missing fragment specifier */
+
+macro_rules! m1 { ($$i) => () }
+/* error: invalid macro definition: `$$` is not allowed on the pattern side */
+macro_rules! m2 { () => ( ${invalid()} ) }
+/* error: invalid macro definition: invalid metavariable expression */
+"#]],
+    )
+}
+
+#[test]
+fn test_rustc_issue_57597() {
+    // <https://github.com/rust-lang/rust/blob/master/src/test/ui/issues/issue-57597.rs>
+    check(
+        r#"
+macro_rules! m0 { ($($($i:ident)?)+) => {}; }
+macro_rules! m1 { ($($($i:ident)?)*) => {}; }
+macro_rules! m2 { ($($($i:ident)?)?) => {}; }
+macro_rules! m3 { ($($($($i:ident)?)?)?) => {}; }
+macro_rules! m4 { ($($($($i:ident)*)?)?) => {}; }
+macro_rules! m5 { ($($($($i:ident)?)*)?) => {}; }
+macro_rules! m6 { ($($($($i:ident)?)?)*) => {}; }
+macro_rules! m7 { ($($($($i:ident)*)*)?) => {}; }
+macro_rules! m8 { ($($($($i:ident)?)*)*) => {}; }
+macro_rules! m9 { ($($($($i:ident)?)*)+) => {}; }
+macro_rules! mA { ($($($($i:ident)+)?)*) => {}; }
+macro_rules! mB { ($($($($i:ident)+)*)?) => {}; }
+
+m0!();
+m1!();
+m2!();
+m3!();
+m4!();
+m5!();
+m6!();
+m7!();
+m8!();
+m9!();
+mA!();
+mB!();
+    "#,
+        expect![[r#"
+macro_rules! m0 { ($($($i:ident)?)+) => {}; }
+macro_rules! m1 { ($($($i:ident)?)*) => {}; }
+macro_rules! m2 { ($($($i:ident)?)?) => {}; }
+macro_rules! m3 { ($($($($i:ident)?)?)?) => {}; }
+macro_rules! m4 { ($($($($i:ident)*)?)?) => {}; }
+macro_rules! m5 { ($($($($i:ident)?)*)?) => {}; }
+macro_rules! m6 { ($($($($i:ident)?)?)*) => {}; }
+macro_rules! m7 { ($($($($i:ident)*)*)?) => {}; }
+macro_rules! m8 { ($($($($i:ident)?)*)*) => {}; }
+macro_rules! m9 { ($($($($i:ident)?)*)+) => {}; }
+macro_rules! mA { ($($($($i:ident)+)?)*) => {}; }
+macro_rules! mB { ($($($($i:ident)+)*)?) => {}; }
+
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+/* error: invalid macro definition: empty token tree in repetition */
+    "#]],
+    );
+}