1 files changed, 79 insertions, 0 deletions
diff --git a/third_party/rust/syn/tests/macros/mod.rs b/third_party/rust/syn/tests/macros/mod.rs
new file mode 100644
index 0000000000..5ca88b083b
--- /dev/null
+++ b/third_party/rust/syn/tests/macros/mod.rs
@@ -0,0 +1,79 @@
+#![allow(unused_macros, unused_macro_rules)]
+
+#[path = "../debug/mod.rs"]
+pub mod debug;
+
+use syn::parse::{Parse, Result};
+
+macro_rules! errorf {
+    ($($tt:tt)*) => {{
+        use ::std::io::Write;
+        let stderr = ::std::io::stderr();
+        write!(stderr.lock(), $($tt)*).unwrap();
+    }};
+}
+
+macro_rules! punctuated {
+    ($($e:expr,)+) => {{
+        let mut seq = ::syn::punctuated::Punctuated::new();
+        $(
+            seq.push($e);
+        )+
+        seq
+    }};
+
+    ($($e:expr),+) => {
+        punctuated!($($e,)+)
+    };
+}
+
+macro_rules! snapshot {
+    ($($args:tt)*) => {
+        snapshot_impl!(() $($args)*)
+    };
+}
+
+macro_rules! snapshot_impl {
+    (($expr:ident) as $t:ty, @$snapshot:literal) => {
+        let $expr = crate::macros::Tokens::parse::<$t>($expr).unwrap();
+        let debug = crate::macros::debug::Lite(&$expr);
+        if !cfg!(miri) {
+            insta::assert_debug_snapshot!(debug, @$snapshot);
+        }
+    };
+    (($($expr:tt)*) as $t:ty, @$snapshot:literal) => {{
+        let syntax_tree = crate::macros::Tokens::parse::<$t>($($expr)*).unwrap();
+        let debug = crate::macros::debug::Lite(&syntax_tree);
+        if !cfg!(miri) {
+            insta::assert_debug_snapshot!(debug, @$snapshot);
+        }
+        syntax_tree
+    }};
+    (($($expr:tt)*) , @$snapshot:literal) => {{
+        let syntax_tree = $($expr)*;
+        let debug = crate::macros::debug::Lite(&syntax_tree);
+        if !cfg!(miri) {
+            insta::assert_debug_snapshot!(debug, @$snapshot);
+        }
+        syntax_tree
+    }};
+    (($($expr:tt)*) $next:tt $($rest:tt)*) => {
+        snapshot_impl!(($($expr)* $next) $($rest)*)
+    };
+}
+
+pub trait Tokens {
+    fn parse<T: Parse>(self) -> Result<T>;
+}
+
+impl<'a> Tokens for &'a str {
+    fn parse<T: Parse>(self) -> Result<T> {
+        syn::parse_str(self)
+    }
+}
+
+impl Tokens for proc_macro2::TokenStream {
+    fn parse<T: Parse>(self) -> Result<T> {
+        syn::parse2(self)
+    }
+}