diff --git a/tests/Cargo.toml b/tests/Cargo.toml
index e173127..7d52122 100644
--- a/tests/Cargo.toml
+++ b/tests/Cargo.toml
@@ -2,7 +2,7 @@
 name = "cargo-expand-test"
 version = "0.0.0"
 authors = ["David Tolnay <dtolnay@gmail.com>"]
-edition = "2018"
+edition = "2021"
 publish = false
 
 [lib]
diff --git a/tests/lib.expand.rs b/tests/lib.expand.rs
index ef0c0d7..7c7169e 100644
--- a/tests/lib.expand.rs
+++ b/tests/lib.expand.rs
@@ -1,7 +1,7 @@
 #![feature(prelude_import)]
 //! Test
 #[prelude_import]
-use std::prelude::rust_2018::*;
+use std::prelude::rust_2021::*;
 #[macro_use]
 extern crate std;
 /// Test