diff --git a/CHANGELOG.md b/CHANGELOG.md index 7e91365c69a3..10111be596ae 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -4250,6 +4250,7 @@ Released 2018-09-13 [`suspicious_splitn`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_splitn [`suspicious_to_owned`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_to_owned [`suspicious_unary_op_formatting`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_unary_op_formatting +[`suspicious_xor_used_as_pow`]: https://rust-lang.github.io/rust-clippy/master/index.html#suspicious_xor_used_as_pow [`swap_ptr_to_ref`]: https://rust-lang.github.io/rust-clippy/master/index.html#swap_ptr_to_ref [`tabs_in_doc_comments`]: https://rust-lang.github.io/rust-clippy/master/index.html#tabs_in_doc_comments [`temporary_assignment`]: https://rust-lang.github.io/rust-clippy/master/index.html#temporary_assignment diff --git a/clippy_lints/src/declared_lints.rs b/clippy_lints/src/declared_lints.rs index a903d46b2a44..35f86e8aa78f 100644 --- a/clippy_lints/src/declared_lints.rs +++ b/clippy_lints/src/declared_lints.rs @@ -543,6 +543,7 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[ crate::suspicious_operation_groupings::SUSPICIOUS_OPERATION_GROUPINGS_INFO, crate::suspicious_trait_impl::SUSPICIOUS_ARITHMETIC_IMPL_INFO, crate::suspicious_trait_impl::SUSPICIOUS_OP_ASSIGN_IMPL_INFO, + crate::suspicious_xor_used_as_pow::SUSPICIOUS_XOR_USED_AS_POW_INFO, crate::swap::ALMOST_SWAPPED_INFO, crate::swap::MANUAL_SWAP_INFO, crate::swap_ptr_to_ref::SWAP_PTR_TO_REF_INFO, diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index 01da11958e2a..197d8f2dc081 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -268,6 +268,7 @@ mod strings; mod strlen_on_c_strings; mod suspicious_operation_groupings; mod suspicious_trait_impl; +mod suspicious_xor_used_as_pow; mod swap; mod swap_ptr_to_ref; mod tabs_in_doc_comments; @@ -916,6 +917,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_early_pass(|| Box::new(partial_pub_fields::PartialPubFields)); store.register_late_pass(|_| Box::new(missing_trait_methods::MissingTraitMethods)); store.register_late_pass(|_| Box::new(from_raw_with_void_ptr::FromRawWithVoidPtr)); + store.register_late_pass(|_| Box::new(suspicious_xor_used_as_pow::ConfusingXorAndPow)); // add lints here, do not remove this comment, it's used in `new_lint` } diff --git a/clippy_lints/src/suspicious_xor_used_as_pow.rs b/clippy_lints/src/suspicious_xor_used_as_pow.rs new file mode 100644 index 000000000000..301aa5798bf5 --- /dev/null +++ b/clippy_lints/src/suspicious_xor_used_as_pow.rs @@ -0,0 +1,53 @@ +use clippy_utils::{numeric_literal::NumericLiteral, source::snippet_with_context}; +use rustc_errors::Applicability; +use rustc_hir::{BinOpKind, Expr, ExprKind}; +use rustc_lint::{LateContext, LateLintPass, LintContext}; +use rustc_middle::lint::in_external_macro; +use rustc_session::{declare_lint_pass, declare_tool_lint}; + +declare_clippy_lint! { + /// ### What it does + /// Warns for a Bitwise XOR (`^`) operator being probably confused as a powering. It will not trigger if any of the numbers are not in decimal. + /// ### Why is this bad? + /// It's most probably a typo and may lead to unexpected behaviours. + /// ### Example + /// ```rust + /// let x = 3_i32 ^ 4_i32; + /// ``` + /// Use instead: + /// ```rust + /// let x = 3_i32.pow(4); + /// ``` + #[clippy::version = "1.66.0"] + pub SUSPICIOUS_XOR_USED_AS_POW, + restriction, + "XOR (`^`) operator possibly used as exponentiation operator" +} +declare_lint_pass!(ConfusingXorAndPow => [SUSPICIOUS_XOR_USED_AS_POW]); + +impl LateLintPass<'_> for ConfusingXorAndPow { + fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) { + if !in_external_macro(cx.sess(), expr.span) && + let ExprKind::Binary(op, left, right) = &expr.kind && + op.node == BinOpKind::BitXor && + left.span.ctxt() == right.span.ctxt() && + let ExprKind::Lit(lit_left) = &left.kind && + let ExprKind::Lit(lit_right) = &right.kind && + let snip_left = snippet_with_context(cx, lit_left.span, lit_left.span.ctxt(), "..", &mut Applicability::MaybeIncorrect) && + let snip_right = snippet_with_context(cx, lit_right.span, lit_right.span.ctxt(), "..", &mut Applicability::MaybeIncorrect) && + let Some(left_val) = NumericLiteral::from_lit_kind(&snip_left.0, &lit_left.node) && + let Some(right_val) = NumericLiteral::from_lit_kind(&snip_right.0, &lit_right.node) && + left_val.is_decimal() && + right_val.is_decimal() { + clippy_utils::diagnostics::span_lint_and_sugg( + cx, + SUSPICIOUS_XOR_USED_AS_POW, + expr.span, + "`^` is not the exponentiation operator", + "did you mean to write", + format!("{}.pow({})", left_val.format(), right_val.format()), + Applicability::MaybeIncorrect, + ); + } + } +} diff --git a/tests/ui/eq_op.rs b/tests/ui/eq_op.rs index 422f9486503d..e73795502652 100644 --- a/tests/ui/eq_op.rs +++ b/tests/ui/eq_op.rs @@ -2,6 +2,7 @@ #![warn(clippy::eq_op)] #![allow(clippy::double_parens, clippy::identity_op, clippy::nonminimal_bool)] +#![allow(clippy::suspicious_xor_used_as_pow)] fn main() { // simple values and comparisons diff --git a/tests/ui/eq_op.stderr b/tests/ui/eq_op.stderr index 313ceed2b41f..d365ab27edc2 100644 --- a/tests/ui/eq_op.stderr +++ b/tests/ui/eq_op.stderr @@ -1,5 +1,5 @@ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:8:13 + --> $DIR/eq_op.rs:9:13 | LL | let _ = 1 == 1; | ^^^^^^ @@ -7,163 +7,163 @@ LL | let _ = 1 == 1; = note: `-D clippy::eq-op` implied by `-D warnings` error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:9:13 + --> $DIR/eq_op.rs:10:13 | LL | let _ = "no" == "no"; | ^^^^^^^^^^^^ error: equal expressions as operands to `!=` - --> $DIR/eq_op.rs:11:13 + --> $DIR/eq_op.rs:12:13 | LL | let _ = false != false; | ^^^^^^^^^^^^^^ error: equal expressions as operands to `<` - --> $DIR/eq_op.rs:12:13 + --> $DIR/eq_op.rs:13:13 | LL | let _ = 1.5 < 1.5; | ^^^^^^^^^ error: equal expressions as operands to `>=` - --> $DIR/eq_op.rs:13:13 + --> $DIR/eq_op.rs:14:13 | LL | let _ = 1u64 >= 1u64; | ^^^^^^^^^^^^ error: equal expressions as operands to `&` - --> $DIR/eq_op.rs:16:13 + --> $DIR/eq_op.rs:17:13 | LL | let _ = (1u32 as u64) & (1u32 as u64); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `^` - --> $DIR/eq_op.rs:19:17 + --> $DIR/eq_op.rs:20:17 | LL | let _ = 1 ^ ((((((1)))))); | ^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `<` - --> $DIR/eq_op.rs:23:13 + --> $DIR/eq_op.rs:24:13 | LL | let _ = (-(2) < -(2)); | ^^^^^^^^^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:24:13 + --> $DIR/eq_op.rs:25:13 | LL | let _ = ((1 + 1) & (1 + 1) == (1 + 1) & (1 + 1)); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `&` - --> $DIR/eq_op.rs:24:14 + --> $DIR/eq_op.rs:25:14 | LL | let _ = ((1 + 1) & (1 + 1) == (1 + 1) & (1 + 1)); | ^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `&` - --> $DIR/eq_op.rs:24:35 + --> $DIR/eq_op.rs:25:35 | LL | let _ = ((1 + 1) & (1 + 1) == (1 + 1) & (1 + 1)); | ^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:25:13 + --> $DIR/eq_op.rs:26:13 | LL | let _ = (1 * 2) + (3 * 4) == 1 * 2 + 3 * 4; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `!=` - --> $DIR/eq_op.rs:28:13 + --> $DIR/eq_op.rs:29:13 | LL | let _ = ([1] != [1]); | ^^^^^^^^^^^^ error: equal expressions as operands to `!=` - --> $DIR/eq_op.rs:29:13 + --> $DIR/eq_op.rs:30:13 | LL | let _ = ((1, 2) != (1, 2)); | ^^^^^^^^^^^^^^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:33:13 + --> $DIR/eq_op.rs:34:13 | LL | let _ = 1 + 1 == 2; | ^^^^^^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:34:13 + --> $DIR/eq_op.rs:35:13 | LL | let _ = 1 - 1 == 0; | ^^^^^^^^^^ error: equal expressions as operands to `-` - --> $DIR/eq_op.rs:34:13 + --> $DIR/eq_op.rs:35:13 | LL | let _ = 1 - 1 == 0; | ^^^^^ error: equal expressions as operands to `-` - --> $DIR/eq_op.rs:36:13 + --> $DIR/eq_op.rs:37:13 | LL | let _ = 1 - 1; | ^^^^^ error: equal expressions as operands to `/` - --> $DIR/eq_op.rs:37:13 + --> $DIR/eq_op.rs:38:13 | LL | let _ = 1 / 1; | ^^^^^ error: equal expressions as operands to `&&` - --> $DIR/eq_op.rs:38:13 + --> $DIR/eq_op.rs:39:13 | LL | let _ = true && true; | ^^^^^^^^^^^^ error: equal expressions as operands to `||` - --> $DIR/eq_op.rs:40:13 + --> $DIR/eq_op.rs:41:13 | LL | let _ = true || true; | ^^^^^^^^^^^^ error: equal expressions as operands to `&&` - --> $DIR/eq_op.rs:45:13 + --> $DIR/eq_op.rs:46:13 | LL | let _ = a == b && b == a; | ^^^^^^^^^^^^^^^^ error: equal expressions as operands to `&&` - --> $DIR/eq_op.rs:46:13 + --> $DIR/eq_op.rs:47:13 | LL | let _ = a != b && b != a; | ^^^^^^^^^^^^^^^^ error: equal expressions as operands to `&&` - --> $DIR/eq_op.rs:47:13 + --> $DIR/eq_op.rs:48:13 | LL | let _ = a < b && b > a; | ^^^^^^^^^^^^^^ error: equal expressions as operands to `&&` - --> $DIR/eq_op.rs:48:13 + --> $DIR/eq_op.rs:49:13 | LL | let _ = a <= b && b >= a; | ^^^^^^^^^^^^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:51:13 + --> $DIR/eq_op.rs:52:13 | LL | let _ = a == a; | ^^^^^^ error: equal expressions as operands to `/` - --> $DIR/eq_op.rs:61:20 + --> $DIR/eq_op.rs:62:20 | LL | const D: u32 = A / A; | ^^^^^ error: equal expressions as operands to `==` - --> $DIR/eq_op.rs:92:5 + --> $DIR/eq_op.rs:93:5 | LL | (n1.inner.0).0 == (n1.inner.0).0 && (n1.inner.1).0 == (n2.inner.1).0 && (n1.inner.2).0 == (n2.inner.2).0 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/tests/ui/suspicious_xor_used_as_pow.rs b/tests/ui/suspicious_xor_used_as_pow.rs new file mode 100644 index 000000000000..eb9fc63fb1d4 --- /dev/null +++ b/tests/ui/suspicious_xor_used_as_pow.rs @@ -0,0 +1,34 @@ +#![allow(unused)] +#![warn(clippy::suspicious_xor_used_as_pow)] +#![allow(clippy::eq_op)] + +macro_rules! macro_test { + () => { + 13 + }; +} + +macro_rules! macro_test_inside { + () => { + 1 ^ 2 // should warn even if inside macro + }; +} + +fn main() { + // Should warn: + let _ = 2 ^ 5; + let _ = 2i32 ^ 9i32; + let _ = 2i32 ^ 2i32; + let _ = 50i32 ^ 3i32; + let _ = 5i32 ^ 8i32; + let _ = 2i32 ^ 32i32; + macro_test_inside!(); + + // Should not warn: + let x = 0x02; + let _ = x ^ 2; + let _ = 2 ^ x; + let _ = x ^ 5; + let _ = 10 ^ 0b0101; + let _ = 2i32 ^ macro_test!(); +} diff --git a/tests/ui/suspicious_xor_used_as_pow.stderr b/tests/ui/suspicious_xor_used_as_pow.stderr new file mode 100644 index 000000000000..8bb3c8fbeebd --- /dev/null +++ b/tests/ui/suspicious_xor_used_as_pow.stderr @@ -0,0 +1,51 @@ +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:19:13 + | +LL | let _ = 2 ^ 5; + | ^^^^^ help: did you mean to write: `2.pow(5)` + | + = note: `-D clippy::suspicious-xor-used-as-pow` implied by `-D warnings` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:20:13 + | +LL | let _ = 2i32 ^ 9i32; + | ^^^^^^^^^^^ help: did you mean to write: `2_i32.pow(9_i32)` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:21:13 + | +LL | let _ = 2i32 ^ 2i32; + | ^^^^^^^^^^^ help: did you mean to write: `2_i32.pow(2_i32)` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:22:13 + | +LL | let _ = 50i32 ^ 3i32; + | ^^^^^^^^^^^^ help: did you mean to write: `50_i32.pow(3_i32)` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:23:13 + | +LL | let _ = 5i32 ^ 8i32; + | ^^^^^^^^^^^ help: did you mean to write: `5_i32.pow(8_i32)` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:24:13 + | +LL | let _ = 2i32 ^ 32i32; + | ^^^^^^^^^^^^ help: did you mean to write: `2_i32.pow(32_i32)` + +error: `^` is not the exponentiation operator + --> $DIR/suspicious_xor_used_as_pow.rs:13:9 + | +LL | 1 ^ 2 // should warn even if inside macro + | ^^^^^ help: did you mean to write: `1.pow(2)` +... +LL | macro_test_inside!(); + | -------------------- in this macro invocation + | + = note: this error originates in the macro `macro_test_inside` (in Nightly builds, run with -Z macro-backtrace for more info) + +error: aborting due to 7 previous errors +