1 files changed, 68 insertions, 0 deletions
diff --git a/tests/ui/traits/wrong-mul-method-signature.rs b/tests/ui/traits/wrong-mul-method-signature.rs
new file mode 100644
index 000000000..1c2f86559
--- /dev/null
+++ b/tests/ui/traits/wrong-mul-method-signature.rs
@@ -0,0 +1,68 @@
+// This test is to make sure we don't just ICE if the trait
+// method for an operator is not implemented properly.
+// (In this case the mul method should take &f64 and not f64)
+// See: #11450
+
+use std::ops::Mul;
+
+struct Vec1 {
+    x: f64
+}
+
+// Expecting value in input signature
+impl Mul<f64> for Vec1 {
+    type Output = Vec1;
+
+    fn mul(self, s: &f64) -> Vec1 {
+    //~^ ERROR method `mul` has an incompatible type for trait
+        Vec1 {
+            x: self.x * *s
+        }
+    }
+}
+
+struct Vec2 {
+    x: f64,
+    y: f64
+}
+
+// Wrong type parameter ordering
+impl Mul<Vec2> for Vec2 {
+    type Output = f64;
+
+    fn mul(self, s: f64) -> Vec2 {
+    //~^ ERROR method `mul` has an incompatible type for trait
+        Vec2 {
+            x: self.x * s,
+            y: self.y * s
+        }
+    }
+}
+
+struct Vec3 {
+    x: f64,
+    y: f64,
+    z: f64
+}
+
+// Unexpected return type
+impl Mul<f64> for Vec3 {
+    type Output = i32;
+
+    fn mul(self, s: f64) -> f64 {
+    //~^ ERROR method `mul` has an incompatible type for trait
+        s
+    }
+}
+
+pub fn main() {
+    // Check that the usage goes from the trait declaration:
+
+    let x: Vec1 = Vec1 { x: 1.0 } * 2.0; // this is OK
+
+    let x: Vec2 = Vec2 { x: 1.0, y: 2.0 } * 2.0; // trait had reversed order
+    //~^ ERROR mismatched types
+    //~| ERROR mismatched types
+
+    let x: i32 = Vec3 { x: 1.0, y: 2.0, z: 3.0 } * 2.0;
+}