diff --git a/clippy_lints/src/operators/assign_op_pattern.rs b/clippy_lints/src/operators/assign_op_pattern.rs index 4be42267b14b..9c6141d82226 100644 --- a/clippy_lints/src/operators/assign_op_pattern.rs +++ b/clippy_lints/src/operators/assign_op_pattern.rs @@ -1,8 +1,10 @@ use clippy_utils::diagnostics::span_lint_and_then; +use clippy_utils::msrvs::Msrv; +use clippy_utils::qualify_min_const_fn::is_stable_const_fn; use clippy_utils::source::SpanRangeExt; use clippy_utils::ty::implements_trait; use clippy_utils::visitors::for_each_expr_without_closures; -use clippy_utils::{binop_traits, eq_expr_value, trait_ref_of_method}; +use clippy_utils::{binop_traits, eq_expr_value, is_in_const_context, trait_ref_of_method}; use core::ops::ControlFlow; use rustc_errors::Applicability; use rustc_hir as hir; @@ -19,6 +21,7 @@ pub(super) fn check<'tcx>( expr: &'tcx hir::Expr<'_>, assignee: &'tcx hir::Expr<'_>, e: &'tcx hir::Expr<'_>, + msrv: Msrv, ) { if let hir::ExprKind::Binary(op, l, r) = &e.kind { let lint = |assignee: &hir::Expr<'_>, rhs: &hir::Expr<'_>| { @@ -40,6 +43,15 @@ pub(super) fn check<'tcx>( return; } } + + // Skip if the trait is not stable in const contexts + if is_in_const_context(cx) + && let Some(binop_id) = cx.tcx.associated_item_def_ids(trait_id).first() + && !is_stable_const_fn(cx, *binop_id, msrv) + { + return; + } + span_lint_and_then( cx, ASSIGN_OP_PATTERN, diff --git a/clippy_lints/src/operators/mod.rs b/clippy_lints/src/operators/mod.rs index d32c062cf56a..2f4e8e995886 100644 --- a/clippy_lints/src/operators/mod.rs +++ b/clippy_lints/src/operators/mod.rs @@ -919,7 +919,7 @@ impl<'tcx> LateLintPass<'tcx> for Operators { modulo_arithmetic::check(cx, e, bin_op, lhs, rhs, false); }, ExprKind::Assign(lhs, rhs, _) => { - assign_op_pattern::check(cx, e, lhs, rhs); + assign_op_pattern::check(cx, e, lhs, rhs, self.msrv); self_assignment::check(cx, e, lhs, rhs); }, ExprKind::Unary(op, arg) => { diff --git a/clippy_utils/src/qualify_min_const_fn.rs b/clippy_utils/src/qualify_min_const_fn.rs index 45da266fd8a9..2bf7eb703d4b 100644 --- a/clippy_utils/src/qualify_min_const_fn.rs +++ b/clippy_utils/src/qualify_min_const_fn.rs @@ -393,7 +393,8 @@ fn check_terminator<'tcx>( } } -fn is_stable_const_fn(cx: &LateContext<'_>, def_id: DefId, msrv: Msrv) -> bool { +/// Checks if the given `def_id` is a stable const fn, in respect to the given MSRV. +pub fn is_stable_const_fn(cx: &LateContext<'_>, def_id: DefId, msrv: Msrv) -> bool { cx.tcx.is_const_fn(def_id) && cx .tcx diff --git a/tests/ui/assign_ops.fixed b/tests/ui/assign_ops.fixed index 429c20f95e91..3bc6885d7c3e 100644 --- a/tests/ui/assign_ops.fixed +++ b/tests/ui/assign_ops.fixed @@ -1,5 +1,6 @@ #![allow(clippy::useless_vec)] #![warn(clippy::assign_op_pattern)] +#![feature(const_trait_impl, const_ops)] use core::num::Wrapping; use std::ops::{Mul, MulAssign}; @@ -73,3 +74,33 @@ impl MulAssign for Wrap { *self = *self * rhs } } + +mod issue14871 { + + use std::ops::{Add, AddAssign}; + + pub trait Number: Copy + Add + AddAssign { + const ZERO: Self; + const ONE: Self; + } + + #[const_trait] + pub trait NumberConstants { + fn constant(value: usize) -> Self; + } + + impl const NumberConstants for T + where + T: Number + ~const core::ops::Add, + { + fn constant(value: usize) -> Self { + let mut res = Self::ZERO; + let mut count = 0; + while count < value { + res = res + Self::ONE; + count += 1; + } + res + } + } +} diff --git a/tests/ui/assign_ops.rs b/tests/ui/assign_ops.rs index 480ff07f150e..f1f8f9daff95 100644 --- a/tests/ui/assign_ops.rs +++ b/tests/ui/assign_ops.rs @@ -1,5 +1,6 @@ #![allow(clippy::useless_vec)] #![warn(clippy::assign_op_pattern)] +#![feature(const_trait_impl, const_ops)] use core::num::Wrapping; use std::ops::{Mul, MulAssign}; @@ -73,3 +74,33 @@ impl MulAssign for Wrap { *self = *self * rhs } } + +mod issue14871 { + + use std::ops::{Add, AddAssign}; + + pub trait Number: Copy + Add + AddAssign { + const ZERO: Self; + const ONE: Self; + } + + #[const_trait] + pub trait NumberConstants { + fn constant(value: usize) -> Self; + } + + impl const NumberConstants for T + where + T: Number + ~const core::ops::Add, + { + fn constant(value: usize) -> Self { + let mut res = Self::ZERO; + let mut count = 0; + while count < value { + res = res + Self::ONE; + count += 1; + } + res + } + } +} diff --git a/tests/ui/assign_ops.stderr b/tests/ui/assign_ops.stderr index 881a333fbe4b..c5e698b3ee11 100644 --- a/tests/ui/assign_ops.stderr +++ b/tests/ui/assign_ops.stderr @@ -1,5 +1,5 @@ error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:9:5 + --> tests/ui/assign_ops.rs:10:5 | LL | a = a + 1; | ^^^^^^^^^ help: replace it with: `a += 1` @@ -8,67 +8,67 @@ LL | a = a + 1; = help: to override `-D warnings` add `#[allow(clippy::assign_op_pattern)]` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:11:5 + --> tests/ui/assign_ops.rs:12:5 | LL | a = 1 + a; | ^^^^^^^^^ help: replace it with: `a += 1` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:13:5 + --> tests/ui/assign_ops.rs:14:5 | LL | a = a - 1; | ^^^^^^^^^ help: replace it with: `a -= 1` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:15:5 + --> tests/ui/assign_ops.rs:16:5 | LL | a = a * 99; | ^^^^^^^^^^ help: replace it with: `a *= 99` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:17:5 + --> tests/ui/assign_ops.rs:18:5 | LL | a = 42 * a; | ^^^^^^^^^^ help: replace it with: `a *= 42` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:19:5 + --> tests/ui/assign_ops.rs:20:5 | LL | a = a / 2; | ^^^^^^^^^ help: replace it with: `a /= 2` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:21:5 + --> tests/ui/assign_ops.rs:22:5 | LL | a = a % 5; | ^^^^^^^^^ help: replace it with: `a %= 5` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:23:5 + --> tests/ui/assign_ops.rs:24:5 | LL | a = a & 1; | ^^^^^^^^^ help: replace it with: `a &= 1` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:30:5 + --> tests/ui/assign_ops.rs:31:5 | LL | s = s + "bla"; | ^^^^^^^^^^^^^ help: replace it with: `s += "bla"` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:35:5 + --> tests/ui/assign_ops.rs:36:5 | LL | a = a + Wrapping(1u32); | ^^^^^^^^^^^^^^^^^^^^^^ help: replace it with: `a += Wrapping(1u32)` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:38:5 + --> tests/ui/assign_ops.rs:39:5 | LL | v[0] = v[0] + v[1]; | ^^^^^^^^^^^^^^^^^^ help: replace it with: `v[0] += v[1]` error: manual implementation of an assign operation - --> tests/ui/assign_ops.rs:51:5 + --> tests/ui/assign_ops.rs:52:5 | LL | buf = buf + cows.clone(); | ^^^^^^^^^^^^^^^^^^^^^^^^ help: replace it with: `buf += cows.clone()`