--- /dev/null
+use clippy_utils::{
+ diagnostics::{self, span_lint_and_sugg},
+ meets_msrv, msrvs, source, ty,
+};
+use rustc_errors::Applicability;
+use rustc_hir::{BinOpKind, Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::{source_map::Spanned, sym};
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// Lints subtraction between `Instant::now()` and another `Instant`.
+ ///
+ /// ### Why is this bad?
+ /// It is easy to accidentally write `prev_instant - Instant::now()`, which will always be 0ns
+ /// as `Instant` subtraction saturates.
+ ///
+ /// `prev_instant.elapsed()` also more clearly signals intention.
+ ///
+ /// ### Example
+ /// ```rust
+ /// use std::time::Instant;
+ /// let prev_instant = Instant::now();
+ /// let duration = Instant::now() - prev_instant;
+ /// ```
+ /// Use instead:
+ /// ```rust
+ /// use std::time::Instant;
+ /// let prev_instant = Instant::now();
+ /// let duration = prev_instant.elapsed();
+ /// ```
+ #[clippy::version = "1.64.0"]
+ pub MANUAL_INSTANT_ELAPSED,
+ pedantic,
+ "subtraction between `Instant::now()` and previous `Instant`"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// Finds patterns of unchecked subtraction of [`Duration`] from [`Instant::now()`].
+ ///
+ /// ### Why is this bad?
+ /// Unchecked subtraction could cause underflow on certain platforms, leading to
+ /// unintentional panics.
+ ///
+ /// ### Example
+ /// ```rust
+ /// let time_passed = Instant::now() - Duration::from_secs(5);
+ /// ```
+ ///
+ /// Use instead:
+ /// ```rust
+ /// let time_passed = Instant::now().checked_sub(Duration::from_secs(5));
+ /// ```
+ ///
+ /// [`Duration`]: std::time::Duration
+ /// [`Instant::now()`]: std::time::Instant::now;
+ #[clippy::version = "1.65.0"]
+ pub UNCHECKED_DURATION_SUBTRACTION,
+ suspicious,
+ "finds unchecked subtraction of a 'Duration' from an 'Instant'"
+}
+
+pub struct InstantSubtraction {
+ msrv: Option<RustcVersion>,
+}
+
+impl InstantSubtraction {
+ #[must_use]
+ pub fn new(msrv: Option<RustcVersion>) -> Self {
+ Self { msrv }
+ }
+}
+
+impl_lint_pass!(InstantSubtraction => [MANUAL_INSTANT_ELAPSED, UNCHECKED_DURATION_SUBTRACTION]);
+
+impl LateLintPass<'_> for InstantSubtraction {
+ fn check_expr(&mut self, cx: &LateContext<'_>, expr: &'_ Expr<'_>) {
+ if let ExprKind::Binary(Spanned {node: BinOpKind::Sub, ..}, lhs, rhs) = expr.kind
+ && check_instant_now_call(cx, lhs)
+ && let ty_resolved = cx.typeck_results().expr_ty(rhs)
+ && let rustc_middle::ty::Adt(def, _) = ty_resolved.kind()
+ && clippy_utils::match_def_path(cx, def.did(), &clippy_utils::paths::INSTANT)
+ && let Some(sugg) = clippy_utils::sugg::Sugg::hir_opt(cx, rhs)
+ {
+ span_lint_and_sugg(
+ cx,
+ MANUAL_INSTANT_ELAPSED,
+ expr.span,
+ "manual implementation of `Instant::elapsed`",
+ "try",
+ format!("{}.elapsed()", sugg.maybe_par()),
+ Applicability::MachineApplicable,
+ );
+ }
+
+ if expr.span.from_expansion() || !meets_msrv(self.msrv, msrvs::TRY_FROM) {
+ return;
+ }
+
+ if_chain! {
+ if let ExprKind::Binary(op, lhs, rhs) = expr.kind;
+
+ if let BinOpKind::Sub = op.node;
+
+ // get types of left and right side
+ if is_an_instant(cx, lhs);
+ if is_a_duration(cx, rhs);
+
+ then {
+ print_lint_and_sugg(cx, lhs, rhs, expr)
+ }
+ }
+ }
+}
+
+fn check_instant_now_call(cx: &LateContext<'_>, expr_block: &'_ Expr<'_>) -> bool {
+ if let ExprKind::Call(fn_expr, []) = expr_block.kind
+ && let Some(fn_id) = clippy_utils::path_def_id(cx, fn_expr)
+ && clippy_utils::match_def_path(cx, fn_id, &clippy_utils::paths::INSTANT_NOW)
+ {
+ true
+ } else {
+ false
+ }
+}
+
+fn is_an_instant(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
+ let expr_ty = cx.typeck_results().expr_ty(expr);
+
+ match expr_ty.kind() {
+ rustc_middle::ty::Adt(def, _) => clippy_utils::match_def_path(cx, def.did(), &clippy_utils::paths::INSTANT),
+ _ => false,
+ }
+}
+
+fn is_a_duration(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
+ let expr_ty = cx.typeck_results().expr_ty(expr);
+ ty::is_type_diagnostic_item(cx, expr_ty, sym::Duration)
+}
+
+fn print_lint_and_sugg(cx: &LateContext<'_>, left_expr: &Expr<'_>, right_expr: &Expr<'_>, expr: &Expr<'_>) {
+ let mut applicability = Applicability::MachineApplicable;
+
+ let left_expr =
+ source::snippet_with_applicability(cx, left_expr.span, "std::time::Instant::now()", &mut applicability);
+ let right_expr = source::snippet_with_applicability(
+ cx,
+ right_expr.span,
+ "std::time::Duration::from_secs(1)",
+ &mut applicability,
+ );
+
+ diagnostics::span_lint_and_sugg(
+ cx,
+ UNCHECKED_DURATION_SUBTRACTION,
+ expr.span,
+ "unchecked subtraction of a 'Duration' from an 'Instant'",
+ "try",
+ format!("{}.checked_sub({}).unwrap();", left_expr, right_expr),
+ applicability,
+ );
+}
mod inherent_to_string;
mod init_numbered_fields;
mod inline_fn_without_body;
+mod instant_subtraction;
mod int_plus_one;
mod invalid_upcast_comparisons;
mod invalid_utf8_in_unchecked;
mod manual_async_fn;
mod manual_bits;
mod manual_clamp;
-mod manual_instant_elapsed;
mod manual_is_ascii_check;
mod manual_let_else;
mod manual_non_exhaustive;
mod trait_bounds;
mod transmute;
mod types;
-mod unchecked_duration_subtraction;
mod undocumented_unsafe_blocks;
mod unicode;
mod uninit_vec;
store.register_late_pass(move |_| Box::new(operators::Operators::new(verbose_bit_mask_threshold)));
store.register_late_pass(|_| Box::new(invalid_utf8_in_unchecked::InvalidUtf8InUnchecked));
store.register_late_pass(|_| Box::<std_instead_of_core::StdReexports>::default());
- store.register_late_pass(|_| Box::new(manual_instant_elapsed::ManualInstantElapsed));
+ store.register_late_pass(move |_| Box::new(instant_subtraction::InstantSubtraction::new(msrv)));
store.register_late_pass(|_| Box::new(partialeq_to_none::PartialeqToNone));
store.register_late_pass(move |_| Box::new(manual_clamp::ManualClamp::new(msrv)));
store.register_late_pass(|_| Box::new(manual_string_new::ManualStringNew));
+++ /dev/null
-use clippy_utils::diagnostics::span_lint_and_sugg;
-use rustc_errors::Applicability;
-use rustc_hir::{BinOpKind, Expr, ExprKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-use rustc_span::source_map::Spanned;
-
-declare_clippy_lint! {
- /// ### What it does
- /// Lints subtraction between `Instant::now()` and another `Instant`.
- ///
- /// ### Why is this bad?
- /// It is easy to accidentally write `prev_instant - Instant::now()`, which will always be 0ns
- /// as `Instant` subtraction saturates.
- ///
- /// `prev_instant.elapsed()` also more clearly signals intention.
- ///
- /// ### Example
- /// ```rust
- /// use std::time::Instant;
- /// let prev_instant = Instant::now();
- /// let duration = Instant::now() - prev_instant;
- /// ```
- /// Use instead:
- /// ```rust
- /// use std::time::Instant;
- /// let prev_instant = Instant::now();
- /// let duration = prev_instant.elapsed();
- /// ```
- #[clippy::version = "1.65.0"]
- pub MANUAL_INSTANT_ELAPSED,
- pedantic,
- "subtraction between `Instant::now()` and previous `Instant`"
-}
-
-declare_lint_pass!(ManualInstantElapsed => [MANUAL_INSTANT_ELAPSED]);
-
-impl LateLintPass<'_> for ManualInstantElapsed {
- fn check_expr(&mut self, cx: &LateContext<'_>, expr: &'_ Expr<'_>) {
- if let ExprKind::Binary(Spanned {node: BinOpKind::Sub, ..}, lhs, rhs) = expr.kind
- && check_instant_now_call(cx, lhs)
- && let ty_resolved = cx.typeck_results().expr_ty(rhs)
- && let rustc_middle::ty::Adt(def, _) = ty_resolved.kind()
- && clippy_utils::match_def_path(cx, def.did(), &clippy_utils::paths::INSTANT)
- && let Some(sugg) = clippy_utils::sugg::Sugg::hir_opt(cx, rhs)
- {
- span_lint_and_sugg(
- cx,
- MANUAL_INSTANT_ELAPSED,
- expr.span,
- "manual implementation of `Instant::elapsed`",
- "try",
- format!("{}.elapsed()", sugg.maybe_par()),
- Applicability::MachineApplicable,
- );
- }
- }
-}
-
-fn check_instant_now_call(cx: &LateContext<'_>, expr_block: &'_ Expr<'_>) -> bool {
- if let ExprKind::Call(fn_expr, []) = expr_block.kind
- && let Some(fn_id) = clippy_utils::path_def_id(cx, fn_expr)
- && clippy_utils::match_def_path(cx, fn_id, &clippy_utils::paths::INSTANT_NOW)
- {
- true
- } else {
- false
- }
-}
+++ /dev/null
-use clippy_utils::{diagnostics, meets_msrv, msrvs, source, ty};
-use rustc_errors::Applicability;
-use rustc_hir::*;
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_semver::RustcVersion;
-use rustc_session::{declare_tool_lint, impl_lint_pass};
-use rustc_span::symbol::sym;
-
-declare_clippy_lint! {
- /// ### What it does
- /// Finds patterns of unchecked subtraction of [`Duration`] from [`Instant::now()`].
- ///
- /// ### Why is this bad?
- /// Unchecked subtraction could cause underflow on certain platforms, leading to bugs and/or
- /// unintentional panics.
- ///
- /// ### Example
- /// ```rust
- /// let time_passed = Instant::now() - Duration::from_secs(5);
- /// ```
- ///
- /// Use instead:
- /// ```rust
- /// let time_passed = Instant::now().checked_sub(Duration::from_secs(5));
- /// ```
- ///
- /// [`Duration`]: std::time::Duration
- /// [`Instant::now()`]: std::time::Instant::now;
- #[clippy::version = "1.65.0"]
- pub UNCHECKED_DURATION_SUBTRACTION,
- suspicious,
- "finds unchecked subtraction of a 'Duration' from an 'Instant'"
-}
-
-pub struct UncheckedDurationSubtraction {
- msrv: Option<RustcVersion>,
-}
-
-impl UncheckedDurationSubtraction {
- #[must_use]
- pub fn new(msrv: Option<RustcVersion>) -> Self {
- Self { msrv }
- }
-}
-
-impl_lint_pass!(UncheckedDurationSubtraction => [UNCHECKED_DURATION_SUBTRACTION]);
-
-impl<'tcx> LateLintPass<'tcx> for UncheckedDurationSubtraction {
- fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
- if expr.span.from_expansion() || !meets_msrv(self.msrv, msrvs::TRY_FROM) {
- return;
- }
-
- if_chain! {
- if let ExprKind::Binary(op, lhs, rhs) = expr.kind;
-
- if let BinOpKind::Sub = op.node;
-
- // get types of left and right side
- if is_an_instant(cx, lhs);
- if is_a_duration(cx, rhs);
-
- then {
- print_lint_and_sugg(cx, lhs, rhs, expr)
- }
- }
- }
-}
-
-fn is_an_instant(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
- let expr_ty = cx.typeck_results().expr_ty(expr);
-
- match expr_ty.kind() {
- rustc_middle::ty::Adt(def, _) => clippy_utils::match_def_path(cx, def.did(), &clippy_utils::paths::INSTANT),
- _ => false,
- }
-}
-
-fn is_a_duration(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
- let expr_ty = cx.typeck_results().expr_ty(expr);
- ty::is_type_diagnostic_item(cx, expr_ty, sym::Duration)
-}
-
-fn print_lint_and_sugg(cx: &LateContext<'_>, left_expr: &Expr<'_>, right_expr: &Expr<'_>, expr: &Expr<'_>) {
- let mut applicability = Applicability::MachineApplicable;
-
- let left_expr =
- source::snippet_with_applicability(cx, left_expr.span, "std::time::Instant::now()", &mut applicability);
- let right_expr = source::snippet_with_applicability(
- cx,
- right_expr.span,
- "std::time::Duration::from_secs(1)",
- &mut applicability,
- );
-
- diagnostics::span_lint_and_sugg(
- cx,
- UNCHECKED_DURATION_SUBTRACTION,
- expr.span,
- "unchecked subtraction of a 'Duration' from an 'Instant'",
- "try",
- format!("{}.checked_sub({}).unwrap();", left_expr, right_expr),
- applicability,
- );
-}
projects / rust.git / commitdiff