1 files changed, 48 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/neg_multiply.rs b/src/tools/clippy/tests/ui/neg_multiply.rs
new file mode 100644
index 000000000..581290dc7
--- /dev/null
+++ b/src/tools/clippy/tests/ui/neg_multiply.rs
@@ -0,0 +1,48 @@
+// run-rustfix
+#![warn(clippy::neg_multiply)]
+#![allow(clippy::no_effect, clippy::unnecessary_operation, clippy::precedence)]
+#![allow(unused)]
+
+use std::ops::Mul;
+
+struct X;
+
+impl Mul<isize> for X {
+    type Output = X;
+
+    fn mul(self, _r: isize) -> Self {
+        self
+    }
+}
+
+impl Mul<X> for isize {
+    type Output = X;
+
+    fn mul(self, _r: X) -> X {
+        X
+    }
+}
+
+fn main() {
+    let x = 0;
+
+    x * -1;
+
+    -1 * x;
+
+    100 + x * -1;
+
+    (100 + x) * -1;
+
+    -1 * 17;
+
+    0xcafe | 0xff00 * -1;
+
+    3_usize as i32 * -1;
+    (3_usize as i32) * -1;
+
+    -1 * -1; // should be ok
+
+    X * -1; // should be ok
+    -1 * X; // should also be ok
+}