1 files changed, 58 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/return_self_not_must_use.rs b/src/tools/clippy/tests/ui/return_self_not_must_use.rs
new file mode 100644
index 000000000..9b33ad6d3
--- /dev/null
+++ b/src/tools/clippy/tests/ui/return_self_not_must_use.rs
@@ -0,0 +1,58 @@
+#![crate_type = "lib"]
+#![warn(clippy::return_self_not_must_use)]
+
+#[derive(Clone)]
+pub struct Bar;
+
+pub trait Whatever {
+    fn what(&self) -> Self;
+    // There should be no warning here! (returns a reference)
+    fn what2(&self) -> &Self;
+}
+
+impl Bar {
+    // There should be no warning here! (note taking a self argument)
+    pub fn not_new() -> Self {
+        Self
+    }
+    pub fn foo(&self) -> Self {
+        Self
+    }
+    pub fn bar(self) -> Self {
+        self
+    }
+    // There should be no warning here! (private method)
+    fn foo2(&self) -> Self {
+        Self
+    }
+    // There should be no warning here! (returns a reference)
+    pub fn foo3(&self) -> &Self {
+        self
+    }
+    // There should be no warning here! (already a `must_use` attribute)
+    #[must_use]
+    pub fn foo4(&self) -> Self {
+        Self
+    }
+}
+
+impl Whatever for Bar {
+    // There should be no warning here! (comes from the trait)
+    fn what(&self) -> Self {
+        self.foo2()
+    }
+    // There should be no warning here! (comes from the trait)
+    fn what2(&self) -> &Self {
+        self
+    }
+}
+
+#[must_use]
+pub struct Foo;
+
+impl Foo {
+    // There should be no warning here! (`Foo` already implements `#[must_use]`)
+    fn foo(&self) -> Self {
+        Self
+    }
+}