diff --git a/clippy_lints/src/lib.register_lints.rs b/clippy_lints/src/lib.register_lints.rs index f0ce0db65a7a..787ae1e79ec0 100644 --- a/clippy_lints/src/lib.register_lints.rs +++ b/clippy_lints/src/lib.register_lints.rs @@ -431,12 +431,12 @@ store.register_lints(&[ non_octal_unix_permissions::NON_OCTAL_UNIX_PERMISSIONS, non_send_fields_in_send_ty::NON_SEND_FIELDS_IN_SEND_TY, nonstandard_macro_braces::NONSTANDARD_MACRO_BRACES, - numeric_arithmetic::FLOAT_ARITHMETIC, - numeric_arithmetic::INTEGER_ARITHMETIC, octal_escapes::OCTAL_ESCAPES, only_used_in_recursion::ONLY_USED_IN_RECURSION, open_options::NONSENSICAL_OPEN_OPTIONS, operators::ABSURD_EXTREME_COMPARISONS, + operators::FLOAT_ARITHMETIC, + operators::INTEGER_ARITHMETIC, option_env_unwrap::OPTION_ENV_UNWRAP, option_if_let_else::OPTION_IF_LET_ELSE, overflow_check_conditional::OVERFLOW_CHECK_CONDITIONAL, diff --git a/clippy_lints/src/lib.register_restriction.rs b/clippy_lints/src/lib.register_restriction.rs index 3695012f5523..b7441385230e 100644 --- a/clippy_lints/src/lib.register_restriction.rs +++ b/clippy_lints/src/lib.register_restriction.rs @@ -50,8 +50,8 @@ store.register_group(true, "clippy::restriction", Some("clippy_restriction"), ve LintId::of(module_style::MOD_MODULE_FILES), LintId::of(module_style::SELF_NAMED_MODULE_FILES), LintId::of(modulo_arithmetic::MODULO_ARITHMETIC), - LintId::of(numeric_arithmetic::FLOAT_ARITHMETIC), - LintId::of(numeric_arithmetic::INTEGER_ARITHMETIC), + LintId::of(operators::FLOAT_ARITHMETIC), + LintId::of(operators::INTEGER_ARITHMETIC), LintId::of(panic_in_result_fn::PANIC_IN_RESULT_FN), LintId::of(panic_unimplemented::PANIC), LintId::of(panic_unimplemented::TODO), diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index 16e72400fbf1..f1d282013091 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -331,7 +331,6 @@ mod non_expressive_names; mod non_octal_unix_permissions; mod non_send_fields_in_send_ty; mod nonstandard_macro_braces; -mod numeric_arithmetic; mod octal_escapes; mod only_used_in_recursion; mod open_options; @@ -705,7 +704,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_late_pass(move || Box::new(doc::DocMarkdown::new(doc_valid_idents.clone()))); store.register_late_pass(|| Box::new(neg_multiply::NegMultiply)); store.register_late_pass(|| Box::new(mem_forget::MemForget)); - store.register_late_pass(|| Box::new(numeric_arithmetic::NumericArithmetic::default())); store.register_late_pass(|| Box::new(assign_ops::AssignOps)); store.register_late_pass(|| Box::new(let_if_seq::LetIfSeq)); store.register_late_pass(|| Box::new(mixed_read_write_in_expression::EvalOrderDependence)); @@ -940,7 +938,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_late_pass(|| Box::new(default_instead_of_iter_empty::DefaultIterEmpty)); store.register_late_pass(move || Box::new(manual_rem_euclid::ManualRemEuclid::new(msrv))); store.register_late_pass(move || Box::new(manual_retain::ManualRetain::new(msrv))); - store.register_late_pass(|| Box::new(operators::Operators)); + store.register_late_pass(|| Box::new(operators::Operators::default())); // add lints here, do not remove this comment, it's used in `new_lint` } diff --git a/clippy_lints/src/numeric_arithmetic.rs b/clippy_lints/src/numeric_arithmetic.rs deleted file mode 100644 index 5c4de3381496..000000000000 --- a/clippy_lints/src/numeric_arithmetic.rs +++ /dev/null @@ -1,170 +0,0 @@ -use clippy_utils::consts::constant_simple; -use clippy_utils::diagnostics::span_lint; -use rustc_hir as hir; -use rustc_lint::{LateContext, LateLintPass}; -use rustc_session::{declare_tool_lint, impl_lint_pass}; -use rustc_span::source_map::Span; - -declare_clippy_lint! { - /// ### What it does - /// Checks for integer arithmetic operations which could overflow or panic. - /// - /// Specifically, checks for any operators (`+`, `-`, `*`, `<<`, etc) which are capable - /// of overflowing according to the [Rust - /// Reference](https://doc.rust-lang.org/reference/expressions/operator-expr.html#overflow), - /// or which can panic (`/`, `%`). No bounds analysis or sophisticated reasoning is - /// attempted. - /// - /// ### Why is this bad? - /// Integer overflow will trigger a panic in debug builds or will wrap in - /// release mode. Division by zero will cause a panic in either mode. In some applications one - /// wants explicitly checked, wrapping or saturating arithmetic. - /// - /// ### Example - /// ```rust - /// # let a = 0; - /// a + 1; - /// ``` - #[clippy::version = "pre 1.29.0"] - pub INTEGER_ARITHMETIC, - restriction, - "any integer arithmetic expression which could overflow or panic" -} - -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. - /// - /// ### Example - /// ```rust - /// # let a = 0.0; - /// a + 1.0; - /// ``` - #[clippy::version = "pre 1.29.0"] - pub FLOAT_ARITHMETIC, - restriction, - "any floating-point arithmetic statement" -} - -#[derive(Copy, Clone, Default)] -pub struct NumericArithmetic { - expr_span: Option, - /// This field is used to check whether expressions are constants, such as in enum discriminants - /// and consts - const_span: Option, -} - -impl_lint_pass!(NumericArithmetic => [INTEGER_ARITHMETIC, FLOAT_ARITHMETIC]); - -impl<'tcx> LateLintPass<'tcx> for NumericArithmetic { - fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>) { - if self.expr_span.is_some() { - return; - } - - 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::BinOpKind::And - | hir::BinOpKind::Or - | hir::BinOpKind::BitAnd - | hir::BinOpKind::BitOr - | hir::BinOpKind::BitXor - | 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.typeck_results().expr_ty(l), cx.typeck_results().expr_ty(r)); - if l_ty.peel_refs().is_integral() && r_ty.peel_refs().is_integral() { - match op.node { - hir::BinOpKind::Div | hir::BinOpKind::Rem => match &r.kind { - hir::ExprKind::Lit(_lit) => (), - hir::ExprKind::Unary(hir::UnOp::Neg, expr) => { - if let hir::ExprKind::Lit(lit) = &expr.kind { - if let rustc_ast::ast::LitKind::Int(1, _) = lit.node { - span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); - self.expr_span = Some(expr.span); - } - } - }, - _ => { - span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); - self.expr_span = Some(expr.span); - }, - }, - _ => { - span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); - self.expr_span = Some(expr.span); - }, - } - } else if r_ty.peel_refs().is_floating_point() && r_ty.peel_refs().is_floating_point() { - span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected"); - self.expr_span = Some(expr.span); - } - }, - hir::ExprKind::Unary(hir::UnOp::Neg, arg) => { - let ty = cx.typeck_results().expr_ty(arg); - if constant_simple(cx, cx.typeck_results(), 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<'tcx>, expr: &'tcx hir::Expr<'_>) { - 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_def_id(body.id()); - - match cx.tcx.hir().body_owner_kind(body_owner) { - hir::BodyOwnerKind::Static(_) | hir::BodyOwnerKind::Const => { - let body_span = cx.tcx.def_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; - } -} diff --git a/clippy_lints/src/operators/mod.rs b/clippy_lints/src/operators/mod.rs index 6f5a16472773..a7495f042da4 100644 --- a/clippy_lints/src/operators/mod.rs +++ b/clippy_lints/src/operators/mod.rs @@ -1,8 +1,9 @@ -use rustc_hir::{Expr, ExprKind}; +use rustc_hir::{Body, Expr, ExprKind, UnOp}; use rustc_lint::{LateContext, LateLintPass}; use rustc_session::{declare_tool_lint, impl_lint_pass}; mod absurd_extreme_comparisons; +mod numeric_arithmetic; declare_clippy_lint! { /// ### What it does @@ -36,16 +37,90 @@ declare_clippy_lint! { "a comparison with a maximum or minimum value that is always true or false" } -pub struct Operators; +declare_clippy_lint! { + /// ### What it does + /// Checks for integer arithmetic operations which could overflow or panic. + /// + /// Specifically, checks for any operators (`+`, `-`, `*`, `<<`, etc) which are capable + /// of overflowing according to the [Rust + /// Reference](https://doc.rust-lang.org/reference/expressions/operator-expr.html#overflow), + /// or which can panic (`/`, `%`). No bounds analysis or sophisticated reasoning is + /// attempted. + /// + /// ### Why is this bad? + /// Integer overflow will trigger a panic in debug builds or will wrap in + /// release mode. Division by zero will cause a panic in either mode. In some applications one + /// wants explicitly checked, wrapping or saturating arithmetic. + /// + /// ### Example + /// ```rust + /// # let a = 0; + /// a + 1; + /// ``` + #[clippy::version = "pre 1.29.0"] + pub INTEGER_ARITHMETIC, + restriction, + "any integer arithmetic expression which could overflow or panic" +} + +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. + /// + /// ### Example + /// ```rust + /// # let a = 0.0; + /// a + 1.0; + /// ``` + #[clippy::version = "pre 1.29.0"] + pub FLOAT_ARITHMETIC, + restriction, + "any floating-point arithmetic statement" +} + +#[derive(Default)] +pub struct Operators { + arithmetic_context: numeric_arithmetic::Context, +} impl_lint_pass!(Operators => [ ABSURD_EXTREME_COMPARISONS, + INTEGER_ARITHMETIC, + FLOAT_ARITHMETIC, ]); impl<'tcx> LateLintPass<'tcx> for Operators { fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) { - if let ExprKind::Binary(op, lhs, rhs) = e.kind { - if !e.span.from_expansion() { - absurd_extreme_comparisons::check(cx, e, op.node, lhs, rhs); - } + match e.kind { + ExprKind::Binary(op, lhs, rhs) => { + if !e.span.from_expansion() { + absurd_extreme_comparisons::check(cx, e, op.node, lhs, rhs); + } + self.arithmetic_context.check_binary(cx, e, op.node, lhs, rhs); + }, + ExprKind::AssignOp(op, lhs, rhs) => { + self.arithmetic_context.check_binary(cx, e, op.node, lhs, rhs); + }, + ExprKind::Unary(op, arg) => { + if op == UnOp::Neg { + self.arithmetic_context.check_negate(cx, e, arg); + } + }, + _ => (), } } + + fn check_expr_post(&mut self, _: &LateContext<'_>, e: &Expr<'_>) { + self.arithmetic_context.expr_post(e.hir_id); + } + + fn check_body(&mut self, cx: &LateContext<'tcx>, b: &'tcx Body<'_>) { + self.arithmetic_context.enter_body(cx, b); + } + + fn check_body_post(&mut self, cx: &LateContext<'tcx>, b: &'tcx Body<'_>) { + self.arithmetic_context.body_post(cx, b); + } } diff --git a/clippy_lints/src/operators/numeric_arithmetic.rs b/clippy_lints/src/operators/numeric_arithmetic.rs new file mode 100644 index 000000000000..82f454d02f71 --- /dev/null +++ b/clippy_lints/src/operators/numeric_arithmetic.rs @@ -0,0 +1,127 @@ +use clippy_utils::consts::constant_simple; +use clippy_utils::diagnostics::span_lint; +use rustc_hir as hir; +use rustc_lint::LateContext; +use rustc_span::source_map::Span; + +use super::{FLOAT_ARITHMETIC, INTEGER_ARITHMETIC}; + +#[derive(Default)] +pub struct Context { + expr_id: Option, + /// This field is used to check whether expressions are constants, such as in enum discriminants + /// and consts + const_span: Option, +} +impl Context { + fn skip_expr(&mut self, e: &hir::Expr<'_>) -> bool { + self.expr_id.is_some() || self.const_span.map_or(false, |span| span.contains(e.span)) + } + + pub fn check_binary<'tcx>( + &mut self, + cx: &LateContext<'tcx>, + expr: &'tcx hir::Expr<'_>, + op: hir::BinOpKind, + l: &'tcx hir::Expr<'_>, + r: &'tcx hir::Expr<'_>, + ) { + if self.skip_expr(expr) { + return; + } + match op { + hir::BinOpKind::And + | hir::BinOpKind::Or + | hir::BinOpKind::BitAnd + | hir::BinOpKind::BitOr + | hir::BinOpKind::BitXor + | 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.typeck_results().expr_ty(l), cx.typeck_results().expr_ty(r)); + if l_ty.peel_refs().is_integral() && r_ty.peel_refs().is_integral() { + match op { + hir::BinOpKind::Div | hir::BinOpKind::Rem => match &r.kind { + hir::ExprKind::Lit(_lit) => (), + hir::ExprKind::Unary(hir::UnOp::Neg, expr) => { + if let hir::ExprKind::Lit(lit) = &expr.kind { + if let rustc_ast::ast::LitKind::Int(1, _) = lit.node { + span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); + self.expr_id = Some(expr.hir_id); + } + } + }, + _ => { + span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); + self.expr_id = Some(expr.hir_id); + }, + }, + _ => { + span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); + self.expr_id = Some(expr.hir_id); + }, + } + } else if r_ty.peel_refs().is_floating_point() && r_ty.peel_refs().is_floating_point() { + span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected"); + self.expr_id = Some(expr.hir_id); + } + } + + pub fn check_negate<'tcx>(&mut self, cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, arg: &'tcx hir::Expr<'_>) { + if self.skip_expr(expr) { + return; + } + let ty = cx.typeck_results().expr_ty(arg); + if constant_simple(cx, cx.typeck_results(), expr).is_none() { + if ty.is_integral() { + span_lint(cx, INTEGER_ARITHMETIC, expr.span, "integer arithmetic detected"); + self.expr_id = Some(expr.hir_id); + } else if ty.is_floating_point() { + span_lint(cx, FLOAT_ARITHMETIC, expr.span, "floating-point arithmetic detected"); + self.expr_id = Some(expr.hir_id); + } + } + } + + pub fn expr_post(&mut self, id: hir::HirId) { + if Some(id) == self.expr_id { + self.expr_id = None; + } + } + + pub fn enter_body(&mut self, cx: &LateContext<'_>, body: &hir::Body<'_>) { + let body_owner = cx.tcx.hir().body_owner_def_id(body.id()); + + match cx.tcx.hir().body_owner_kind(body_owner) { + hir::BodyOwnerKind::Static(_) | hir::BodyOwnerKind::Const => { + let body_span = cx.tcx.def_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 => (), + } + } + + pub fn 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; + } +}