use if_chain::if_chain;
-use rustc::hir::*;
-use rustc::lint::{in_external_macro, LateContext, LateLintPass, LintArray, LintContext, LintPass};
-use rustc::{declare_tool_lint, lint_array};
+use rustc_hir::{BinOpKind, Expr, ExprKind, UnOp};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_middle::lint::in_external_macro;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
use crate::utils::{self, paths, span_lint};
-/// **What it does:**
-/// Checks for the usage of negated comparison operators on types which only implement
-/// `PartialOrd` (e.g. `f64`).
-///
-/// **Why is this bad?**
-/// These operators make it easy to forget that the underlying types actually allow not only three
-/// potential Orderings (Less, Equal, Greater) but also a fourth one (Uncomparable). This is
-/// especially easy to miss if the operator based comparison result is negated.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-///
-/// ```rust
-/// use std::cmp::Ordering;
-///
-/// // Bad
-/// let a = 1.0;
-/// let b = std::f64::NAN;
-///
-/// let _not_less_or_equal = !(a <= b);
-///
-/// // Good
-/// let a = 1.0;
-/// let b = std::f64::NAN;
-///
-/// let _not_less_or_equal = match a.partial_cmp(&b) {
-/// None | Some(Ordering::Greater) => true,
-/// _ => false,
-/// };
-/// ```
declare_clippy_lint! {
+ /// **What it does:**
+ /// Checks for the usage of negated comparison operators on types which only implement
+ /// `PartialOrd` (e.g., `f64`).
+ ///
+ /// **Why is this bad?**
+ /// These operators make it easy to forget that the underlying types actually allow not only three
+ /// potential Orderings (Less, Equal, Greater) but also a fourth one (Uncomparable). This is
+ /// especially easy to miss if the operator based comparison result is negated.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ ///
+ /// ```rust
+ /// use std::cmp::Ordering;
+ ///
+ /// // Bad
+ /// let a = 1.0;
+ /// let b = f64::NAN;
+ ///
+ /// let _not_less_or_equal = !(a <= b);
+ ///
+ /// // Good
+ /// let a = 1.0;
+ /// let b = f64::NAN;
+ ///
+ /// let _not_less_or_equal = match a.partial_cmp(&b) {
+ /// None | Some(Ordering::Greater) => true,
+ /// _ => false,
+ /// };
+ /// ```
pub NEG_CMP_OP_ON_PARTIAL_ORD,
complexity,
"The use of negated comparison operators on partially ordered types may produce confusing code."
}
-pub struct NoNegCompOpForPartialOrd;
+declare_lint_pass!(NoNegCompOpForPartialOrd => [NEG_CMP_OP_ON_PARTIAL_ORD]);
-impl LintPass for NoNegCompOpForPartialOrd {
- fn get_lints(&self) -> LintArray {
- lint_array!(NEG_CMP_OP_ON_PARTIAL_ORD)
- }
-
- fn name(&self) -> &'static str {
- "NoNegCompOpForPartialOrd"
- }
-}
-
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for NoNegCompOpForPartialOrd {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
+impl<'tcx> LateLintPass<'tcx> for NoNegCompOpForPartialOrd {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
if_chain! {
if !in_external_macro(cx.sess(), expr.span);
- if let ExprKind::Unary(UnOp::UnNot, ref inner) = expr.node;
- if let ExprKind::Binary(ref op, ref left, _) = inner.node;
+ if let ExprKind::Unary(UnOp::Not, ref inner) = expr.kind;
+ if let ExprKind::Binary(ref op, ref left, _) = inner.kind;
if let BinOpKind::Le | BinOpKind::Ge | BinOpKind::Lt | BinOpKind::Gt = op.node;
then {
- let ty = cx.tables.expr_ty(left);
+ let ty = cx.typeck_results().expr_ty(left);
let implements_ord = {
if let Some(id) = utils::get_trait_def_id(cx, &paths::ORD) {
};
let implements_partial_ord = {
- if let Some(id) = utils::get_trait_def_id(cx, &paths::PARTIAL_ORD) {
+ if let Some(id) = cx.tcx.lang_items().partial_ord_trait() {
utils::implements_trait(cx, ty, id, &[])
} else {
return;
cx,
NEG_CMP_OP_ON_PARTIAL_ORD,
expr.span,
- "The use of negated comparison operators on partially ordered \
- types produces code that is hard to read and refactor. Please \
+ "the use of negated comparison operators on partially ordered \
+ types produces code that is hard to read and refactor, please \
consider using the `partial_cmp` method instead, to make it \
- clear that the two values could be incomparable."
+ clear that the two values could be incomparable"
)
}
}