diff --git a/clippy_lints/src/manual_option_as_slice.rs b/clippy_lints/src/manual_option_as_slice.rs index 922db174e3d4..b036e78cdedc 100644 --- a/clippy_lints/src/manual_option_as_slice.rs +++ b/clippy_lints/src/manual_option_as_slice.rs @@ -1,7 +1,7 @@ use clippy_config::Conf; use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg}; use clippy_utils::msrvs::Msrv; -use clippy_utils::{is_none_arm, msrvs, peel_hir_expr_refs, sym}; +use clippy_utils::{is_none_pattern, msrvs, peel_hir_expr_refs, sym}; use rustc_errors::Applicability; use rustc_hir::def::{DefKind, Res}; use rustc_hir::{Arm, Expr, ExprKind, LangItem, Pat, PatKind, QPath, is_range_literal}; @@ -60,8 +60,8 @@ impl LateLintPass<'_> for ManualOptionAsSlice { } match expr.kind { ExprKind::Match(scrutinee, [arm1, arm2], _) => { - if is_none_arm(cx, arm2) && check_arms(cx, arm2, arm1) - || is_none_arm(cx, arm1) && check_arms(cx, arm1, arm2) + if is_none_pattern(cx, arm2.pat) && check_arms(cx, arm2, arm1) + || is_none_pattern(cx, arm1.pat) && check_arms(cx, arm1, arm2) { check_as_ref(cx, scrutinee, span, self.msrv); } diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs index 5223cd872a68..3e48397fbedb 100644 --- a/clippy_utils/src/lib.rs +++ b/clippy_utils/src/lib.rs @@ -329,13 +329,17 @@ pub fn is_wild(pat: &Pat<'_>) -> bool { matches!(pat.kind, PatKind::Wild) } -// Checks if arm has the form `None => None` -pub fn is_none_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool { - matches!( - arm.pat.kind, +/// Checks if the `pat` is `None`. +pub fn is_none_pattern(cx: &LateContext<'_>, pat: &Pat<'_>) -> bool { + matches!(pat.kind, PatKind::Expr(PatExpr { kind: PatExprKind::Path(qpath), .. }) - if is_res_lang_ctor(cx, cx.qpath_res(qpath, arm.pat.hir_id), OptionNone) - ) + if is_res_lang_ctor(cx, cx.qpath_res(qpath, pat.hir_id), OptionNone)) +} + +/// Checks if `arm` has the form `None => None`. +pub fn is_none_arm(cx: &LateContext<'_>, arm: &Arm<'_>) -> bool { + is_none_pattern(cx, arm.pat) + && matches!(peel_blocks(arm.body).kind, ExprKind::Path(qpath) if is_res_lang_ctor(cx, cx.qpath_res(&qpath, arm.body.hir_id), OptionNone)) } /// Checks if the given `QPath` belongs to a type alias. diff --git a/tests/ui/match_as_ref.fixed b/tests/ui/match_as_ref.fixed index 8c07076af4a4..a39f0c9299bd 100644 --- a/tests/ui/match_as_ref.fixed +++ b/tests/ui/match_as_ref.fixed @@ -41,3 +41,33 @@ fn main() { None => None, }; } + +mod issue15691 { + use std::ops::{Deref, DerefMut}; + + struct A(B); + struct B; + + impl Deref for A { + type Target = B; + fn deref(&self) -> &Self::Target { + &self.0 + } + } + + impl DerefMut for A { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } + } + + fn func() { + let mut a = Some(A(B)); + let mut b = Some(B); + // Do not lint, we don't have `None => None` + let _ = match b { + Some(ref mut x) => Some(x), + None => a.as_deref_mut(), + }; + } +} diff --git a/tests/ui/match_as_ref.rs b/tests/ui/match_as_ref.rs index 3a5b1227331e..049928167901 100644 --- a/tests/ui/match_as_ref.rs +++ b/tests/ui/match_as_ref.rs @@ -53,3 +53,33 @@ fn main() { None => None, }; } + +mod issue15691 { + use std::ops::{Deref, DerefMut}; + + struct A(B); + struct B; + + impl Deref for A { + type Target = B; + fn deref(&self) -> &Self::Target { + &self.0 + } + } + + impl DerefMut for A { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } + } + + fn func() { + let mut a = Some(A(B)); + let mut b = Some(B); + // Do not lint, we don't have `None => None` + let _ = match b { + Some(ref mut x) => Some(x), + None => a.as_deref_mut(), + }; + } +}