rust/clippy_lints/src/operators/double_comparison.rs

55 lines
2.1 KiB
Rust

use clippy_utils::diagnostics::span_lint_and_sugg;
use clippy_utils::eq_expr_value;
use clippy_utils::source::snippet_with_applicability;
use rustc_errors::Applicability;
use rustc_hir::{BinOpKind, Expr, ExprKind};
use rustc_lint::LateContext;
use rustc_span::source_map::Span;
use super::DOUBLE_COMPARISONS;
#[expect(clippy::similar_names)]
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, op: BinOpKind, lhs: &'tcx Expr<'_>, rhs: &'tcx Expr<'_>, span: Span) {
let (lkind, llhs, lrhs, rkind, rlhs, rrhs) = match (&lhs.kind, &rhs.kind) {
(ExprKind::Binary(lb, llhs, lrhs), ExprKind::Binary(rb, rlhs, rrhs)) => {
(lb.node, llhs, lrhs, rb.node, rlhs, rrhs)
},
_ => return,
};
if !(eq_expr_value(cx, llhs, rlhs) && eq_expr_value(cx, lrhs, rrhs)) {
return;
}
macro_rules! lint_double_comparison {
($op:tt) => {{
let mut applicability = Applicability::MachineApplicable;
let lhs_str = snippet_with_applicability(cx, llhs.span, "", &mut applicability);
let rhs_str = snippet_with_applicability(cx, lrhs.span, "", &mut applicability);
let sugg = format!("{} {} {}", lhs_str, stringify!($op), rhs_str);
span_lint_and_sugg(
cx,
DOUBLE_COMPARISONS,
span,
"this binary expression can be simplified",
"try",
sugg,
applicability,
);
}};
}
match (op, lkind, rkind) {
(BinOpKind::Or, BinOpKind::Eq, BinOpKind::Lt) | (BinOpKind::Or, BinOpKind::Lt, BinOpKind::Eq) => {
lint_double_comparison!(<=);
},
(BinOpKind::Or, BinOpKind::Eq, BinOpKind::Gt) | (BinOpKind::Or, BinOpKind::Gt, BinOpKind::Eq) => {
lint_double_comparison!(>=);
},
(BinOpKind::Or, BinOpKind::Lt, BinOpKind::Gt) | (BinOpKind::Or, BinOpKind::Gt, BinOpKind::Lt) => {
lint_double_comparison!(!=);
},
(BinOpKind::And, BinOpKind::Le, BinOpKind::Ge) | (BinOpKind::And, BinOpKind::Ge, BinOpKind::Le) => {
lint_double_comparison!(==);
},
_ => (),
};
}