1 files changed, 54 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/let_underscore_untyped.rs b/src/tools/clippy/tests/ui/let_underscore_untyped.rs
new file mode 100644
index 000000000..bcb33c5c7
--- /dev/null
+++ b/src/tools/clippy/tests/ui/let_underscore_untyped.rs
@@ -0,0 +1,54 @@
+#![allow(unused)]
+#![warn(clippy::let_underscore_untyped)]
+
+use std::future::Future;
+use std::{boxed::Box, fmt::Display};
+
+fn a() -> u32 {
+    1
+}
+
+fn b<T>(x: T) -> T {
+    x
+}
+
+fn c() -> impl Display {
+    1
+}
+
+fn d(x: &u32) -> &u32 {
+    x
+}
+
+fn e() -> Result<u32, ()> {
+    Ok(1)
+}
+
+fn f() -> Box<dyn Display> {
+    Box::new(1)
+}
+
+fn main() {
+    let _ = a();
+    let _ = b(1);
+    let _ = c();
+    let _ = d(&1);
+    let _ = e();
+    let _ = f();
+
+    _ = a();
+    _ = b(1);
+    _ = c();
+    _ = d(&1);
+    _ = e();
+    _ = f();
+
+    let _: u32 = a();
+    let _: u32 = b(1);
+    let _: &u32 = d(&1);
+    let _: Result<_, _> = e();
+    let _: Box<_> = f();
+
+    #[allow(clippy::let_underscore_untyped)]
+    let _ = a();
+}