v0: add exponential explosion test.
diff --git a/src/v0.rs b/src/v0.rs
index cd8e24d..e976d89 100644
--- a/src/v0.rs
+++ b/src/v0.rs
@@ -1009,6 +1009,11 @@
assert_eq!(format!("{:#}", ::demangle($a)), $b);
})
}
+ macro_rules! t_nohash_type {
+ ($a:expr, $b:expr) => (
+ t_nohash!(concat!("_RMC0", $a), concat!("<", $b, ">"))
+ )
+ }
#[test]
fn demangle_utf8_idents() {
@@ -1042,9 +1047,25 @@
fn demangle_const_generics() {
// NOTE(eddyb) this was hand-written, before rustc had working
// const generics support (but the mangling format did include them).
- t_nohash!(
- "_RNvINtC8arrayvec8ArrayVechKj7b_E3new",
- "arrayvec::ArrayVec::<u8, 123>::new"
+ t_nohash_type!(
+ "INtC8arrayvec8ArrayVechKj7b_E",
+ "arrayvec::ArrayVec<u8, 123>"
+ );
+ }
+
+ #[test]
+ fn demangle_exponential_explosion() {
+ // NOTE(eddyb) because of the prefix added by `t_nohash_type!` is
+ // 3 bytes long, `B2_` refers to the start of the type, not `B_`.
+ // 6 backrefs (`B8_E` through `B3_E`) result in 2^6 = 64 copies of `_`.
+ // Also, because the `p` (`_`) type is after all of the starts of the
+ // backrefs, it can be replaced with any other type, independently.
+ t_nohash_type!(
+ concat!("TTTTTT", "p", "B8_E", "B7_E", "B6_E", "B5_E", "B4_E", "B3_E"),
+ "((((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _)))), \
+ ((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _))))), \
+ (((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _)))), \
+ ((((_, _), (_, _)), ((_, _), (_, _))), (((_, _), (_, _)), ((_, _), (_, _))))))"
);
}
}
