-use crate::consts::{constant, Constant};
-use crate::utils::{sext, span_lint_and_then};
+use clippy_utils::consts::{constant, Constant};
+use clippy_utils::diagnostics::span_lint_and_then;
+use clippy_utils::sext;
use if_chain::if_chain;
use rustc_hir::{BinOpKind, Expr, ExprKind};
use rustc_lint::{LateContext, LateLintPass};
-use rustc_middle::ty::{self};
+use rustc_middle::ty;
use rustc_session::{declare_lint_pass, declare_tool_lint};
use std::fmt::Display;
declare_clippy_lint! {
- /// **What it does:** Checks for modulo arithemtic.
+ /// ### What it does
+ /// Checks for modulo arithmetic.
///
- /// **Why is this bad?** The results of modulo (%) operation might differ
+ /// ### Why is this bad?
+ /// The results of modulo (%) operation might differ
/// depending on the language, when negative numbers are involved.
/// If you interop with different languages it might be beneficial
/// to double check all places that use modulo arithmetic.
///
/// For example, in Rust `17 % -3 = 2`, but in Python `17 % -3 = -1`.
///
- /// **Known problems:** None.
- ///
- /// **Example:**
+ /// ### Example
/// ```rust
/// let x = -17 % 3;
/// ```
+ #[clippy::version = "1.42.0"]
pub MODULO_ARITHMETIC,
restriction,
"any modulo arithmetic statement"
is_integral: bool,
}
-fn analyze_operand(operand: &Expr<'_>, cx: &LateContext<'_, '_>, expr: &Expr<'_>) -> Option<OperandInfo> {
- match constant(cx, cx.tables, operand) {
- Some((Constant::Int(v), _)) => match cx.tables.expr_ty(expr).kind {
+fn analyze_operand(operand: &Expr<'_>, cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<OperandInfo> {
+ match constant(cx, cx.typeck_results(), operand) {
+ Some((Constant::Int(v), _)) => match *cx.typeck_results().expr_ty(expr).kind() {
ty::Int(ity) => {
let value = sext(cx.tcx, v, ity);
return Some(OperandInfo {
t.is_signed() || t.is_floating_point()
}
-fn check_const_operands<'a, 'tcx>(
- cx: &LateContext<'a, 'tcx>,
+fn check_const_operands<'tcx>(
+ cx: &LateContext<'tcx>,
expr: &'tcx Expr<'_>,
lhs_operand: &OperandInfo,
rhs_operand: &OperandInfo,
lhs_operand.string_representation.as_ref().unwrap(),
rhs_operand.string_representation.as_ref().unwrap()
),
- |db| {
- db.note("double check for expected result especially when interoperating with different languages");
+ |diag| {
+ diag.note("double check for expected result especially when interoperating with different languages");
if lhs_operand.is_integral {
- db.note("or consider using `rem_euclid` or similar function");
+ diag.note("or consider using `rem_euclid` or similar function");
}
},
);
}
}
-fn check_non_const_operands<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>, operand: &Expr<'_>) {
- let operand_type = cx.tables.expr_ty(operand);
+fn check_non_const_operands<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, operand: &Expr<'_>) {
+ let operand_type = cx.typeck_results().expr_ty(operand);
if might_have_negative_value(operand_type) {
span_lint_and_then(
cx,
MODULO_ARITHMETIC,
expr.span,
"you are using modulo operator on types that might have different signs",
- |db| {
- db.note("double check for expected result especially when interoperating with different languages");
+ |diag| {
+ diag.note("double check for expected result especially when interoperating with different languages");
if operand_type.is_integral() {
- db.note("or consider using `rem_euclid` or similar function");
+ diag.note("or consider using `rem_euclid` or similar function");
}
},
);
}
}
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ModuloArithmetic {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
+impl<'tcx> LateLintPass<'tcx> for ModuloArithmetic {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
match &expr.kind {
ExprKind::Binary(op, lhs, rhs) | ExprKind::AssignOp(op, lhs, rhs) => {
- if let BinOpKind::Rem = op.node {
+ if op.node == BinOpKind::Rem {
let lhs_operand = analyze_operand(lhs, cx, expr);
let rhs_operand = analyze_operand(rhs, cx, expr);
if_chain! {