Merging upstream version 1.71.1+dfsg1.

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

1 files changed, 98 insertions, 0 deletions

diff --git a/tests/ui/lint/dropping_copy_types.rs b/tests/ui/lint/dropping_copy_types.rs
new file mode 100644
index 000000000..2412222d6
--- /dev/null
+++ b/tests/ui/lint/dropping_copy_types.rs
@@ -0,0 +1,98 @@
+// check-pass
+
+#![warn(dropping_copy_types)]
+
+use std::mem::drop;
+use std::vec::Vec;
+
+#[derive(Copy, Clone)]
+struct SomeStruct;
+
+struct AnotherStruct {
+    x: u8,
+    y: u8,
+    z: Vec<u8>,
+}
+
+impl Clone for AnotherStruct {
+    fn clone(&self) -> AnotherStruct {
+        AnotherStruct {
+            x: self.x,
+            y: self.y,
+            z: self.z.clone(),
+        }
+    }
+}
+
+fn main() {
+    let s1 = SomeStruct {};
+    let s2 = s1;
+    let s3 = &s1;
+    let mut s4 = s1;
+    let ref s5 = s1;
+
+    drop(s1); //~ WARN calls to `std::mem::drop`
+    drop(s2); //~ WARN calls to `std::mem::drop`
+    drop(s3); //~ WARN calls to `std::mem::drop`
+    drop(s4); //~ WARN calls to `std::mem::drop`
+    drop(s5); //~ WARN calls to `std::mem::drop`
+
+    let a1 = AnotherStruct {
+        x: 255,
+        y: 0,
+        z: vec![1, 2, 3],
+    };
+    let a2 = &a1;
+    let mut a3 = a1.clone();
+    let ref a4 = a1;
+    let a5 = a1.clone();
+
+    drop(a2); //~ WARN calls to `std::mem::drop`
+    drop(a3);
+    drop(a4); //~ WARN calls to `std::mem::drop`
+    drop(a5);
+}
+
+#[allow(unused)]
+#[allow(clippy::unit_cmp)]
+fn issue9482(x: u8) {
+    fn println_and<T>(t: T) -> T {
+        println!("foo");
+        t
+    }
+
+    match x {
+        // Don't lint (copy type), we only care about side-effects
+        0 => drop(println_and(12)),
+        // Don't lint (no copy type), we only care about side-effects
+        1 => drop(println_and(String::new())),
+        2 => {
+            // Lint, even if we only care about the side-effect, it's already in a block
+            drop(println_and(13)); //~ WARN calls to `std::mem::drop`
+        },
+         // Lint, idiomatic use is only in body of `Arm`
+        3 if drop(println_and(14)) == () => (), //~ WARN calls to `std::mem::drop`
+        // Lint, not a fn/method call
+        4 => drop(2),//~ WARN calls to `std::mem::drop`
+        _ => (),
+    }
+}
+
+fn issue112653() {
+    fn foo() -> Result<u8, ()> {
+        println!("doing foo");
+        Ok(0) // result is not always useful, the side-effect matters
+    }
+    fn bar() {
+        println!("doing bar");
+    }
+
+    fn stuff() -> Result<(), ()> {
+        match 42 {
+            0 => drop(foo()?),  // drop is needed because we only care about side-effects
+            1 => bar(),
+            _ => (),  // doing nothing (no side-effects needed here)
+        }
+        Ok(())
+    }
+}