1 files changed, 224 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/arithmetic_side_effects.rs b/src/tools/clippy/tests/ui/arithmetic_side_effects.rs
new file mode 100644
index 000000000..b25e68f13
--- /dev/null
+++ b/src/tools/clippy/tests/ui/arithmetic_side_effects.rs
@@ -0,0 +1,224 @@
+#![allow(
+    clippy::assign_op_pattern,
+    clippy::erasing_op,
+    clippy::identity_op,
+    clippy::op_ref,
+    clippy::unnecessary_owned_empty_strings,
+    arithmetic_overflow,
+    unconditional_panic
+)]
+#![feature(const_mut_refs, inline_const, saturating_int_impl)]
+#![warn(clippy::arithmetic_side_effects)]
+
+use core::num::{Saturating, Wrapping};
+
+pub struct Custom;
+
+macro_rules! impl_arith {
+    ( $( $_trait:ident, $ty:ty, $method:ident; )* ) => {
+        $(
+            impl core::ops::$_trait<$ty> for Custom {
+                type Output = Self;
+                fn $method(self, _: $ty) -> Self::Output { Self }
+            }
+        )*
+    }
+}
+
+impl_arith!(
+    Add, i32, add;
+    Div, i32, div;
+    Mul, i32, mul;
+    Sub, i32, sub;
+
+    Add, f64, add;
+    Div, f64, div;
+    Mul, f64, mul;
+    Sub, f64, sub;
+);
+
+pub fn association_with_structures_should_not_trigger_the_lint() {
+    enum Foo {
+        Bar = -2,
+    }
+
+    impl Trait for Foo {
+        const ASSOC: i32 = {
+            let _: [i32; 1 + 1];
+            fn foo() {}
+            1 + 1
+        };
+    }
+
+    struct Baz([i32; 1 + 1]);
+
+    trait Trait {
+        const ASSOC: i32 = 1 + 1;
+    }
+
+    type Alias = [i32; 1 + 1];
+
+    union Qux {
+        field: [i32; 1 + 1],
+    }
+
+    let _: [i32; 1 + 1] = [0, 0];
+
+    let _: [i32; 1 + 1] = {
+        let a: [i32; 1 + 1] = [0, 0];
+        a
+    };
+}
+
+pub fn hard_coded_allowed() {
+    let _ = 1f32 + 1f32;
+    let _ = 1f64 + 1f64;
+
+    let _ = Saturating(0u32) + Saturating(0u32);
+    let _ = String::new() + "";
+    let _ = Wrapping(0u32) + Wrapping(0u32);
+
+    let saturating: Saturating<u32> = Saturating(0u32);
+    let string: String = String::new();
+    let wrapping: Wrapping<u32> = Wrapping(0u32);
+
+    let inferred_saturating = saturating + saturating;
+    let inferred_string = string + "";
+    let inferred_wrapping = wrapping + wrapping;
+
+    let _ = inferred_saturating + inferred_saturating;
+    let _ = inferred_string + "";
+    let _ = inferred_wrapping + inferred_wrapping;
+}
+
+#[rustfmt::skip]
+pub fn const_ops_should_not_trigger_the_lint() {
+    const _: i32 = { let mut n = 1; n += 1; n };
+    let _ = const { let mut n = 1; n += 1; n };
+
+    const _: i32 = { let mut n = 1; n = n + 1; n };
+    let _ = const { let mut n = 1; n = n + 1; n };
+
+    const _: i32 = { let mut n = 1; n = 1 + n; n };
+    let _ = const { let mut n = 1; n = 1 + n; n };
+
+    const _: i32 = 1 + 1;
+    let _ = const { 1 + 1 };
+
+    const _: i32 = { let mut n = 1; n = -1; n = -(-1); n = -n; n };
+    let _ = const { let mut n = 1; n = -1; n = -(-1); n = -n; n };
+}
+
+pub fn non_overflowing_ops_or_ops_already_handled_by_the_compiler_should_not_trigger_the_lint() {
+    let mut _n = i32::MAX;
+
+    // Assign
+    _n += 0;
+    _n += &0;
+    _n -= 0;
+    _n -= &0;
+    _n /= 99;
+    _n /= &99;
+    _n %= 99;
+    _n %= &99;
+    _n *= 0;
+    _n *= &0;
+    _n *= 1;
+    _n *= &1;
+
+    // Binary
+    _n = _n + 0;
+    _n = _n + &0;
+    _n = 0 + _n;
+    _n = &0 + _n;
+    _n = _n - 0;
+    _n = _n - &0;
+    _n = 0 - _n;
+    _n = &0 - _n;
+    _n = _n / 99;
+    _n = _n / &99;
+    _n = _n % 99;
+    _n = _n % &99;
+    _n = _n * 0;
+    _n = _n * &0;
+    _n = 0 * _n;
+    _n = &0 * _n;
+    _n = _n * 1;
+    _n = _n * &1;
+    _n = 1 * _n;
+    _n = &1 * _n;
+    _n = 23 + 85;
+
+    // Unary
+    _n = -1;
+    _n = -(-1);
+}
+
+pub fn runtime_ops() {
+    let mut _n = i32::MAX;
+
+    // Assign
+    _n += 1;
+    _n += &1;
+    _n -= 1;
+    _n -= &1;
+    _n /= 0;
+    _n /= &0;
+    _n %= 0;
+    _n %= &0;
+    _n *= 2;
+    _n *= &2;
+
+    // Binary
+    _n = _n + 1;
+    _n = _n + &1;
+    _n = 1 + _n;
+    _n = &1 + _n;
+    _n = _n - 1;
+    _n = _n - &1;
+    _n = 1 - _n;
+    _n = &1 - _n;
+    _n = _n / 0;
+    _n = _n / &0;
+    _n = _n % 0;
+    _n = _n % &0;
+    _n = _n * 2;
+    _n = _n * &2;
+    _n = 2 * _n;
+    _n = &2 * _n;
+    _n = 23 + &85;
+    _n = &23 + 85;
+    _n = &23 + &85;
+
+    // Custom
+    let _ = Custom + 0;
+    let _ = Custom + 1;
+    let _ = Custom + 2;
+    let _ = Custom + 0.0;
+    let _ = Custom + 1.0;
+    let _ = Custom + 2.0;
+    let _ = Custom - 0;
+    let _ = Custom - 1;
+    let _ = Custom - 2;
+    let _ = Custom - 0.0;
+    let _ = Custom - 1.0;
+    let _ = Custom - 2.0;
+    let _ = Custom / 0;
+    let _ = Custom / 1;
+    let _ = Custom / 2;
+    let _ = Custom / 0.0;
+    let _ = Custom / 1.0;
+    let _ = Custom / 2.0;
+    let _ = Custom * 0;
+    let _ = Custom * 1;
+    let _ = Custom * 2;
+    let _ = Custom * 0.0;
+    let _ = Custom * 1.0;
+    let _ = Custom * 2.0;
+
+    // Unary
+    _n = -_n;
+    _n = -&_n;
+}
+
+fn main() {}