chore: add vendor dependencies for kauma build

vendor/syn/tests/test_iterators.rs

@@ -0,0 +1,89 @@
+#![allow(clippy::map_unwrap_or, clippy::uninlined_format_args)]
+
+use syn::punctuated::{Pair, Punctuated};
+use syn::{parse_quote, GenericParam, Generics, Lifetime, LifetimeParam, Token};
+
+#[macro_use]
+mod macros;
+
+macro_rules! check_exact_size_iterator {
+    ($iter:expr) => {{
+        let iter = $iter;
+        let size_hint = iter.size_hint();
+        let len = iter.len();
+        let count = iter.count();
+        assert_eq!(len, count);
+        assert_eq!(size_hint, (count, Some(count)));
+    }};
+}
+
+#[test]
+fn pairs() {
+    let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+
+    check_exact_size_iterator!(p.pairs());
+    check_exact_size_iterator!(p.pairs_mut());
+    check_exact_size_iterator!(p.into_pairs());
+
+    let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+
+    assert_eq!(p.pairs().next_back().map(Pair::into_value), Some(&4));
+    assert_eq!(
+        p.pairs_mut().next_back().map(Pair::into_value),
+        Some(&mut 4)
+    );
+    assert_eq!(p.into_pairs().next_back().map(Pair::into_value), Some(4));
+}
+
+#[test]
+fn iter() {
+    let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+
+    check_exact_size_iterator!(p.iter());
+    check_exact_size_iterator!(p.iter_mut());
+    check_exact_size_iterator!(p.into_iter());
+
+    let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+
+    assert_eq!(p.iter().next_back(), Some(&4));
+    assert_eq!(p.iter_mut().next_back(), Some(&mut 4));
+    assert_eq!(p.into_iter().next_back(), Some(4));
+}
+
+#[test]
+fn may_dangle() {
+    let p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+    for element in &p {
+        if *element == 2 {
+            drop(p);
+            break;
+        }
+    }
+
+    let mut p: Punctuated<_, Token![,]> = punctuated!(2, 3, 4);
+    for element in &mut p {
+        if *element == 2 {
+            drop(p);
+            break;
+        }
+    }
+}
+
+// Regression test for https://github.com/dtolnay/syn/issues/1718
+#[test]
+fn no_opaque_drop() {
+    let mut generics = Generics::default();
+
+    let _ = generics
+        .lifetimes()
+        .next()
+        .map(|param| param.lifetime.clone())
+        .unwrap_or_else(|| {
+            let lifetime: Lifetime = parse_quote!('a);
+            generics.params.insert(
+                0,
+                GenericParam::Lifetime(LifetimeParam::new(lifetime.clone())),
+            );
+            lifetime
+        });
+}