diff --git a/CHANGELOG.md b/CHANGELOG.md index e2004c2931d5..59719080e440 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -4941,6 +4941,8 @@ Released 2018-09-13 [`manual_flatten`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_flatten [`manual_instant_elapsed`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_instant_elapsed [`manual_is_ascii_check`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_is_ascii_check +[`manual_is_finite`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_is_finite +[`manual_is_infinite`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_is_infinite [`manual_let_else`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_let_else [`manual_main_separator_str`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_main_separator_str [`manual_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#manual_map diff --git a/README.md b/README.md index d712d3e67507..5d490645d897 100644 --- a/README.md +++ b/README.md @@ -5,7 +5,7 @@ A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code. -[There are over 600 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html) +[There are over 650 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html) Lints are divided into categories, each with a default [lint level](https://doc.rust-lang.org/rustc/lints/levels.html). You can choose how much Clippy is supposed to ~~annoy~~ help you by changing the lint level by category. diff --git a/book/src/README.md b/book/src/README.md index 3b6270962680..486ea3df7042 100644 --- a/book/src/README.md +++ b/book/src/README.md @@ -6,7 +6,7 @@ A collection of lints to catch common mistakes and improve your [Rust](https://github.com/rust-lang/rust) code. -[There are over 600 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html) +[There are over 650 lints included in this crate!](https://rust-lang.github.io/rust-clippy/master/index.html) Lints are divided into categories, each with a default [lint level](https://doc.rust-lang.org/rustc/lints/levels.html). You can choose how diff --git a/clippy_lints/src/declared_lints.rs b/clippy_lints/src/declared_lints.rs index ca97db040792..f8b8b94dd29a 100644 --- a/clippy_lints/src/declared_lints.rs +++ b/clippy_lints/src/declared_lints.rs @@ -273,6 +273,8 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[ crate::manual_async_fn::MANUAL_ASYNC_FN_INFO, crate::manual_bits::MANUAL_BITS_INFO, crate::manual_clamp::MANUAL_CLAMP_INFO, + crate::manual_float_methods::MANUAL_IS_FINITE_INFO, + crate::manual_float_methods::MANUAL_IS_INFINITE_INFO, crate::manual_is_ascii_check::MANUAL_IS_ASCII_CHECK_INFO, crate::manual_let_else::MANUAL_LET_ELSE_INFO, crate::manual_main_separator_str::MANUAL_MAIN_SEPARATOR_STR_INFO, diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index 00d46025caa8..9abcbe01176d 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -184,6 +184,7 @@ mod manual_assert; mod manual_async_fn; mod manual_bits; mod manual_clamp; +mod manual_float_methods; mod manual_is_ascii_check; mod manual_let_else; mod manual_main_separator_str; @@ -1073,6 +1074,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_late_pass(|_| Box::new(manual_range_patterns::ManualRangePatterns)); store.register_early_pass(|| Box::new(visibility::Visibility)); store.register_late_pass(move |_| Box::new(tuple_array_conversions::TupleArrayConversions { msrv: msrv() })); + store.register_late_pass(|_| Box::new(manual_float_methods::ManualFloatMethods)); // add lints here, do not remove this comment, it's used in `new_lint` } diff --git a/clippy_lints/src/manual_float_methods.rs b/clippy_lints/src/manual_float_methods.rs new file mode 100644 index 000000000000..09b39634333f --- /dev/null +++ b/clippy_lints/src/manual_float_methods.rs @@ -0,0 +1,175 @@ +use clippy_utils::{ + consts::{constant, Constant}, + diagnostics::span_lint_and_then, + is_from_proc_macro, path_to_local, + source::snippet_opt, +}; +use rustc_errors::Applicability; +use rustc_hir::{BinOpKind, Expr, ExprKind}; +use rustc_lint::{LateContext, LateLintPass, Lint, LintContext}; +use rustc_middle::lint::in_external_macro; +use rustc_session::{declare_lint_pass, declare_tool_lint}; + +declare_clippy_lint! { + /// ### What it does + /// Checks for manual `is_infinite` reimplementations + /// (i.e., `x == ::INFINITY || x == ::NEG_INFINITY`). + /// + /// ### Why is this bad? + /// The method `is_infinite` is shorter and more readable. + /// + /// ### Example + /// ```rust + /// # let x = 1.0f32; + /// if x == f32::INFINITY || x == f32::NEG_INFINITY {} + /// ``` + /// Use instead: + /// ```rust + /// # let x = 1.0f32; + /// if x.is_infinite() {} + /// ``` + #[clippy::version = "1.72.0"] + pub MANUAL_IS_INFINITE, + style, + "use dedicated method to check if a float is infinite" +} +declare_clippy_lint! { + /// ### What it does + /// Checks for manual `is_finite` reimplementations + /// (i.e., `x != ::INFINITY && x != ::NEG_INFINITY`). + /// + /// ### Why is this bad? + /// The method `is_finite` is shorter and more readable. + /// + /// ### Example + /// ```rust + /// # let x = 1.0f32; + /// if x != f32::INFINITY && x != f32::NEG_INFINITY {} + /// if x.abs() < f32::INFINITY {} + /// ``` + /// Use instead: + /// ```rust + /// # let x = 1.0f32; + /// if x.is_finite() {} + /// if x.is_finite() {} + /// ``` + #[clippy::version = "1.72.0"] + pub MANUAL_IS_FINITE, + style, + "use dedicated method to check if a float is finite" +} +declare_lint_pass!(ManualFloatMethods => [MANUAL_IS_INFINITE, MANUAL_IS_FINITE]); + +#[derive(Clone, Copy)] +enum Variant { + ManualIsInfinite, + ManualIsFinite, +} + +impl Variant { + pub fn lint(self) -> &'static Lint { + match self { + Self::ManualIsInfinite => MANUAL_IS_INFINITE, + Self::ManualIsFinite => MANUAL_IS_FINITE, + } + } + + pub fn msg(self) -> &'static str { + match self { + Self::ManualIsInfinite => "manually checking if a float is infinite", + Self::ManualIsFinite => "manually checking if a float is finite", + } + } +} + +impl<'tcx> LateLintPass<'tcx> for ManualFloatMethods { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) { + if !in_external_macro(cx.sess(), expr.span) + && (!cx.param_env.is_const() || cx.tcx.features().active(sym!(const_float_classify))) + && let ExprKind::Binary(kind, lhs, rhs) = expr.kind + && let ExprKind::Binary(lhs_kind, lhs_lhs, lhs_rhs) = lhs.kind + && let ExprKind::Binary(rhs_kind, rhs_lhs, rhs_rhs) = rhs.kind + // Checking all possible scenarios using a function would be a hopeless task, as we have + // 16 possible alignments of constants/operands. For now, let's use `partition`. + && let (operands, constants) = [lhs_lhs, lhs_rhs, rhs_lhs, rhs_rhs] + .into_iter() + .partition::>, _>(|i| path_to_local(i).is_some()) + && let [first, second] = &*operands + && let Some([const_1, const_2]) = constants + .into_iter() + .map(|i| constant(cx, cx.typeck_results(), i)) + .collect::>>() + .as_deref() + && path_to_local(first).is_some_and(|f| path_to_local(second).is_some_and(|s| f == s)) + // The actual infinity check, we also allow `NEG_INFINITY` before` INFINITY` just in + // case somebody does that for some reason + && (is_infinity(const_1) && is_neg_infinity(const_2) + || is_neg_infinity(const_1) && is_infinity(const_2)) + && !is_from_proc_macro(cx, expr) + && let Some(local_snippet) = snippet_opt(cx, first.span) + { + let variant = match (kind.node, lhs_kind.node, rhs_kind.node) { + (BinOpKind::Or, BinOpKind::Eq, BinOpKind::Eq) => Variant::ManualIsInfinite, + (BinOpKind::And, BinOpKind::Ne, BinOpKind::Ne) => Variant::ManualIsFinite, + _ => return, + }; + + span_lint_and_then( + cx, + variant.lint(), + expr.span, + variant.msg(), + |diag| { + match variant { + Variant::ManualIsInfinite => { + diag.span_suggestion( + expr.span, + "use the dedicated method instead", + format!("{local_snippet}.is_infinite()"), + Applicability::MachineApplicable, + ); + }, + Variant::ManualIsFinite => { + // TODO: There's probably some better way to do this, i.e., create + // multiple suggestions with notes between each of them + diag.span_suggestion_verbose( + expr.span, + "use the dedicated method instead", + format!("{local_snippet}.is_finite()"), + Applicability::MaybeIncorrect, + ) + .span_suggestion_verbose( + expr.span, + "this will alter how it handles NaN; if that is a problem, use instead", + format!("{local_snippet}.is_finite() || {local_snippet}.is_nan()"), + Applicability::MaybeIncorrect, + ) + .span_suggestion_verbose( + expr.span, + "or, for conciseness", + format!("!{local_snippet}.is_infinite()"), + Applicability::MaybeIncorrect, + ); + }, + } + }, + ); + } + } +} + +fn is_infinity(constant: &Constant<'_>) -> bool { + match constant { + Constant::F32(float) => *float == f32::INFINITY, + Constant::F64(float) => *float == f64::INFINITY, + _ => false, + } +} + +fn is_neg_infinity(constant: &Constant<'_>) -> bool { + match constant { + Constant::F32(float) => *float == f32::NEG_INFINITY, + Constant::F64(float) => *float == f64::NEG_INFINITY, + _ => false, + } +} diff --git a/tests/ui/manual_float_methods.rs b/tests/ui/manual_float_methods.rs new file mode 100644 index 000000000000..af9076cfb71f --- /dev/null +++ b/tests/ui/manual_float_methods.rs @@ -0,0 +1,55 @@ +//@aux-build:proc_macros.rs:proc-macro +#![allow(clippy::needless_if, unused)] +#![warn(clippy::manual_is_infinite, clippy::manual_is_finite)] +#![feature(inline_const)] + +#[macro_use] +extern crate proc_macros; + +const INFINITE: f32 = f32::INFINITY; +const NEG_INFINITE: f32 = f32::NEG_INFINITY; + +fn fn_test() -> f64 { + f64::NEG_INFINITY +} + +fn fn_test_not_inf() -> f64 { + 112.0 +} + +fn main() { + let x = 1.0f32; + if x == f32::INFINITY || x == f32::NEG_INFINITY {} + if x != f32::INFINITY && x != f32::NEG_INFINITY {} + if x == INFINITE || x == NEG_INFINITE {} + if x != INFINITE && x != NEG_INFINITE {} + let x = 1.0f64; + if x == f64::INFINITY || x == f64::NEG_INFINITY {} + if x != f64::INFINITY && x != f64::NEG_INFINITY {} + // Don't lint + if x.is_infinite() {} + if x.is_finite() {} + if x.abs() < f64::INFINITY {} + if f64::INFINITY > x.abs() {} + if f64::abs(x) < f64::INFINITY {} + if f64::INFINITY > f64::abs(x) {} + // Is not evaluated by `clippy_utils::constant` + if x != f64::INFINITY && x != fn_test() {} + // Not -inf + if x != f64::INFINITY && x != fn_test_not_inf() {} + const X: f64 = 1.0f64; + // Will be linted if `const_float_classify` is enabled + if const { X == f64::INFINITY || X == f64::NEG_INFINITY } {} + if const { X != f64::INFINITY && X != f64::NEG_INFINITY } {} + external! { + let x = 1.0; + if x == f32::INFINITY || x == f32::NEG_INFINITY {} + if x != f32::INFINITY && x != f32::NEG_INFINITY {} + } + with_span! { + span + let x = 1.0; + if x == f32::INFINITY || x == f32::NEG_INFINITY {} + if x != f32::INFINITY && x != f32::NEG_INFINITY {} + } +} diff --git a/tests/ui/manual_float_methods.stderr b/tests/ui/manual_float_methods.stderr new file mode 100644 index 000000000000..a56118b316ae --- /dev/null +++ b/tests/ui/manual_float_methods.stderr @@ -0,0 +1,80 @@ +error: manually checking if a float is infinite + --> $DIR/manual_float_methods.rs:22:8 + | +LL | if x == f32::INFINITY || x == f32::NEG_INFINITY {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the dedicated method instead: `x.is_infinite()` + | + = note: `-D clippy::manual-is-infinite` implied by `-D warnings` + +error: manually checking if a float is finite + --> $DIR/manual_float_methods.rs:23:8 + | +LL | if x != f32::INFINITY && x != f32::NEG_INFINITY {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = note: `-D clippy::manual-is-finite` implied by `-D warnings` +help: use the dedicated method instead + | +LL | if x.is_finite() {} + | ~~~~~~~~~~~~~ +help: this will alter how it handles NaN; if that is a problem, use instead + | +LL | if x.is_finite() || x.is_nan() {} + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ +help: or, for conciseness + | +LL | if !x.is_infinite() {} + | ~~~~~~~~~~~~~~~~ + +error: manually checking if a float is infinite + --> $DIR/manual_float_methods.rs:24:8 + | +LL | if x == INFINITE || x == NEG_INFINITE {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the dedicated method instead: `x.is_infinite()` + +error: manually checking if a float is finite + --> $DIR/manual_float_methods.rs:25:8 + | +LL | if x != INFINITE && x != NEG_INFINITE {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: use the dedicated method instead + | +LL | if x.is_finite() {} + | ~~~~~~~~~~~~~ +help: this will alter how it handles NaN; if that is a problem, use instead + | +LL | if x.is_finite() || x.is_nan() {} + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ +help: or, for conciseness + | +LL | if !x.is_infinite() {} + | ~~~~~~~~~~~~~~~~ + +error: manually checking if a float is infinite + --> $DIR/manual_float_methods.rs:27:8 + | +LL | if x == f64::INFINITY || x == f64::NEG_INFINITY {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use the dedicated method instead: `x.is_infinite()` + +error: manually checking if a float is finite + --> $DIR/manual_float_methods.rs:28:8 + | +LL | if x != f64::INFINITY && x != f64::NEG_INFINITY {} + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: use the dedicated method instead + | +LL | if x.is_finite() {} + | ~~~~~~~~~~~~~ +help: this will alter how it handles NaN; if that is a problem, use instead + | +LL | if x.is_finite() || x.is_nan() {} + | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ +help: or, for conciseness + | +LL | if !x.is_infinite() {} + | ~~~~~~~~~~~~~~~~ + +error: aborting due to 6 previous errors +