Merging upstream version 1.68.2+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 63 insertions, 0 deletions

diff --git a/tests/ui/lint/let_underscore/let_underscore_drop.rs b/tests/ui/lint/let_underscore/let_underscore_drop.rs
new file mode 100644
index 000000000..f298871f1
--- /dev/null
+++ b/tests/ui/lint/let_underscore/let_underscore_drop.rs
@@ -0,0 +1,14 @@
+// check-pass
+#![warn(let_underscore_drop)]
+
+struct NontrivialDrop;
+
+impl Drop for NontrivialDrop {
+    fn drop(&mut self) {
+        println!("Dropping!");
+    }
+}
+
+fn main() {
+    let _ = NontrivialDrop; //~WARNING non-binding let on a type that implements `Drop`
+}
diff --git a/tests/ui/lint/let_underscore/let_underscore_drop.stderr b/tests/ui/lint/let_underscore/let_underscore_drop.stderr
new file mode 100644
index 000000000..7b7de202e
--- /dev/null
+++ b/tests/ui/lint/let_underscore/let_underscore_drop.stderr
@@ -0,0 +1,22 @@
+warning: non-binding let on a type that implements `Drop`
+  --> $DIR/let_underscore_drop.rs:13:5
+   |
+LL |     let _ = NontrivialDrop;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+note: the lint level is defined here
+  --> $DIR/let_underscore_drop.rs:2:9
+   |
+LL | #![warn(let_underscore_drop)]
+   |         ^^^^^^^^^^^^^^^^^^^
+help: consider binding to an unused variable to avoid immediately dropping the value
+   |
+LL |     let _unused = NontrivialDrop;
+   |         ~~~~~~~
+help: consider immediately dropping the value
+   |
+LL |     drop(NontrivialDrop);
+   |     ~~~~~              +
+
+warning: 1 warning emitted
+
diff --git a/tests/ui/lint/let_underscore/let_underscore_lock.rs b/tests/ui/lint/let_underscore/let_underscore_lock.rs
new file mode 100644
index 000000000..7423862cd
--- /dev/null
+++ b/tests/ui/lint/let_underscore/let_underscore_lock.rs
@@ -0,0 +1,7 @@
+// check-fail
+use std::sync::{Arc, Mutex};
+
+fn main() {
+    let data = Arc::new(Mutex::new(0));
+    let _ = data.lock().unwrap(); //~ERROR non-binding let on a synchronization lock
+}
diff --git a/tests/ui/lint/let_underscore/let_underscore_lock.stderr b/tests/ui/lint/let_underscore/let_underscore_lock.stderr
new file mode 100644
index 000000000..fb58af0a4
--- /dev/null
+++ b/tests/ui/lint/let_underscore/let_underscore_lock.stderr
@@ -0,0 +1,20 @@
+error: non-binding let on a synchronization lock
+  --> $DIR/let_underscore_lock.rs:6:9
+   |
+LL |     let _ = data.lock().unwrap();
+   |         ^   ^^^^^^^^^^^^^^^^^^^^ this binding will immediately drop the value assigned to it
+   |         |
+   |         this lock is not assigned to a binding and is immediately dropped
+   |
+   = note: `#[deny(let_underscore_lock)]` on by default
+help: consider binding to an unused variable to avoid immediately dropping the value
+   |
+LL |     let _unused = data.lock().unwrap();
+   |         ~~~~~~~
+help: consider immediately dropping the value
+   |
+LL |     drop(data.lock().unwrap());
+   |     ~~~~~                    +
+
+error: aborting due to previous error
+