+use crate::consts::constant_simple;
use crate::utils::span_lint;
use rustc::hir;
-use rustc::lint::*;
-use syntax::codemap::Span;
+use rustc::impl_lint_pass;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc_session::declare_tool_lint;
+use syntax::source_map::Span;
-/// **What it does:** Checks for plain integer arithmetic.
-///
-/// **Why is this bad?** This is only checked against overflow in debug builds.
-/// In some applications one wants explicitly checked, wrapping or saturating
-/// arithmetic.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// a + 1
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for plain integer arithmetic.
+ ///
+ /// **Why is this bad?** This is only checked against overflow in debug builds.
+ /// In some applications one wants explicitly checked, wrapping or saturating
+ /// arithmetic.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// # let a = 0;
+ /// a + 1;
+ /// ```
pub INTEGER_ARITHMETIC,
restriction,
"any integer arithmetic statement"
}
-/// **What it does:** Checks for float arithmetic.
-///
-/// **Why is this bad?** For some embedded systems or kernel development, it
-/// can be useful to rule out floating-point numbers.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// a + 1.0
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for float arithmetic.
+ ///
+ /// **Why is this bad?** For some embedded systems or kernel development, it
+ /// can be useful to rule out floating-point numbers.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// # let a = 0.0;
+ /// a + 1.0;
+ /// ```
pub FLOAT_ARITHMETIC,
restriction,
"any floating-point arithmetic statement"
#[derive(Copy, Clone, Default)]
pub struct Arithmetic {
- span: Option<Span>,
+ expr_span: Option<Span>,
+ /// This field is used to check whether expressions are constants, such as in enum discriminants
+ /// and consts
+ const_span: Option<Span>,
}
-impl LintPass for Arithmetic {
- fn get_lints(&self) -> LintArray {
- lint_array!(INTEGER_ARITHMETIC, FLOAT_ARITHMETIC)
- }
-}
+impl_lint_pass!(Arithmetic => [INTEGER_ARITHMETIC, FLOAT_ARITHMETIC]);
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Arithmetic {
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
- if self.span.is_some() {
+ if self.expr_span.is_some() {
return;
}
- match expr.node {
- hir::ExprKind::Binary(ref op, ref l, ref r) => {
+
+ if let Some(span) = self.const_span {
+ if span.contains(expr.span) {
+ return;
+ }
+ }
+ match &expr.kind {
+ hir::ExprKind::Binary(op, l, r) | hir::ExprKind::AssignOp(op, l, r) => {
match op.node {
- hir::BiAnd
- | hir::BiOr
- | hir::BiBitAnd
- | hir::BiBitOr
- | hir::BiBitXor
- | hir::BiShl
- | hir::BiShr
- | hir::BiEq
- | hir::BiLt
- | hir::BiLe
- | hir::BiNe
- | hir::BiGe
- | hir::BiGt => return,
+ hir::BinOpKind::And
+ | hir::BinOpKind::Or
+ | hir::BinOpKind::BitAnd
+ | hir::BinOpKind::BitOr
+ | hir::BinOpKind::BitXor
+ | hir::BinOpKind::Shl
+ | hir::BinOpKind::Shr
+ | hir::BinOpKind::Eq
+ | hir::BinOpKind::Lt
+ | hir::BinOpKind::Le
+ | hir::BinOpKind::Ne
+ | hir::BinOpKind::Ge
+ | hir::BinOpKind::Gt => return,
_ => (),
}
let (l_ty, r_ty) = (cx.tables.expr_ty(l), cx.tables.expr_ty(r));
if l_ty.is_integral() && r_ty.is_integral() {
span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected");
- self.span = Some(expr.span);
+ self.expr_span = Some(expr.span);
} else if l_ty.is_floating_point() && r_ty.is_floating_point() {
span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected");
- self.span = Some(expr.span);
+ self.expr_span = Some(expr.span);
}
},
- hir::ExprKind::Unary(hir::UnOp::UnNeg, ref arg) => {
+ hir::ExprKind::Unary(hir::UnOp::UnNeg, arg) => {
let ty = cx.tables.expr_ty(arg);
- if ty.is_integral() {
- span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected");
- self.span = Some(expr.span);
- } else if ty.is_floating_point() {
- span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected");
- self.span = Some(expr.span);
+ if constant_simple(cx, cx.tables, expr).is_none() {
+ if ty.is_integral() {
+ span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected");
+ self.expr_span = Some(expr.span);
+ } else if ty.is_floating_point() {
+ span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected");
+ self.expr_span = Some(expr.span);
+ }
}
},
_ => (),
}
fn check_expr_post(&mut self, _: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr) {
- if Some(expr.span) == self.span {
- self.span = None;
+ if Some(expr.span) == self.expr_span {
+ self.expr_span = None;
+ }
+ }
+
+ fn check_body(&mut self, cx: &LateContext<'_, '_>, body: &hir::Body<'_>) {
+ let body_owner = cx.tcx.hir().body_owner(body.id());
+
+ match cx.tcx.hir().body_owner_kind(body_owner) {
+ hir::BodyOwnerKind::Static(_) | hir::BodyOwnerKind::Const => {
+ let body_span = cx.tcx.hir().span(body_owner);
+
+ if let Some(span) = self.const_span {
+ if span.contains(body_span) {
+ return;
+ }
+ }
+ self.const_span = Some(body_span);
+ },
+ hir::BodyOwnerKind::Fn | hir::BodyOwnerKind::Closure => (),
+ }
+ }
+
+ fn check_body_post(&mut self, cx: &LateContext<'_, '_>, body: &hir::Body<'_>) {
+ let body_owner = cx.tcx.hir().body_owner(body.id());
+ let body_span = cx.tcx.hir().span(body_owner);
+
+ if let Some(span) = self.const_span {
+ if span.contains(body_span) {
+ return;
+ }
}
+ self.const_span = None;
}
}
projects / rust.git / blobdiff