Make must_use lint cover all binary/unary operators

src/test/ui/lint/must-use-ops.rs

@@ -0,0 +1,52 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Issue #50124 - Test warning for unused operator expressions
+
+// compile-pass
+
+#![feature(fn_must_use)]
+#![warn(unused_must_use)]
+
+fn main() {
+    let val = 1;
+    let val_pointer = &val;
+
+// Comparison Operators
+    val == 1;
+    val < 1;
+    val <= 1;
+    val != 1;
+    val >= 1;
+    val > 1;
+
+// Arithmetic Operators
+    val + 2;
+    val - 2;
+    val / 2;
+    val * 2;
+    val % 2;
+
+// Logical Operators
+    true && true;
+    false || true;
+
+// Bitwise Operators
+    5 ^ val;
+    5 & val;
+    5 | val;
+    5 << val;
+    5 >> val;
+
+// Unary Operators
+    !val;
+    -val;
+    *val_pointer;
+}