diff options
| -rw-r--r-- | clippy_lints/src/manual_unwrap_or_default.rs | 9 | ||||
| -rw-r--r-- | tests/ui/manual_unwrap_or_default.fixed | 10 | ||||
| -rw-r--r-- | tests/ui/manual_unwrap_or_default.rs | 10 | ||||
| -rw-r--r-- | tests/ui/manual_unwrap_or_default.stderr | 2 |
4 files changed, 30 insertions, 1 deletions
diff --git a/clippy_lints/src/manual_unwrap_or_default.rs b/clippy_lints/src/manual_unwrap_or_default.rs index c562ceb5bce..a4048e89926 100644 --- a/clippy_lints/src/manual_unwrap_or_default.rs +++ b/clippy_lints/src/manual_unwrap_or_default.rs @@ -3,6 +3,7 @@ use rustc_errors::Applicability; use rustc_hir::def::Res; use rustc_hir::{Arm, Expr, ExprKind, HirId, LangItem, MatchSource, Pat, PatKind, QPath}; use rustc_lint::{LateContext, LateLintPass, LintContext}; +use rustc_middle::ty::GenericArgKind; use rustc_session::declare_lint_pass; use rustc_span::sym; @@ -118,6 +119,10 @@ fn handle_match<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool { && implements_trait(cx, match_ty, default_trait_id, &[]) // We now get the bodies for both the `Some` and `None` arms. && let Some(((body_some, binding_id), body_none)) = get_some_and_none_bodies(cx, arm1, arm2) + // We check that the initial expression also implies the `Default` trait. + && let Some(match_expr_ty) = cx.typeck_results().expr_ty(match_expr).walk().nth(1) + && let GenericArgKind::Type(match_expr_ty) = match_expr_ty.unpack() + && implements_trait(cx, match_expr_ty, default_trait_id, &[]) // We check that the `Some(x) => x` doesn't do anything apart "returning" the value in `Some`. && let ExprKind::Path(QPath::Resolved(_, path)) = peel_blocks(body_some).kind && let Res::Local(local_id) = path.res @@ -154,6 +159,10 @@ fn handle_if_let<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) { && let Some(default_trait_id) = cx.tcx.get_diagnostic_item(sym::Default) && implements_trait(cx, match_ty, default_trait_id, &[]) && let Some(binding_id) = get_some(cx, let_.pat) + // We check that the initial expression also implies the `Default` trait. + && let Some(let_ty) = cx.typeck_results().expr_ty(let_.init).walk().nth(1) + && let GenericArgKind::Type(let_ty) = let_ty.unpack() + && implements_trait(cx, let_ty, default_trait_id, &[]) // We check that the `Some(x) => x` doesn't do anything apart "returning" the value in `Some`. && let ExprKind::Path(QPath::Resolved(_, path)) = peel_blocks(if_block).kind && let Res::Local(local_id) = path.res diff --git a/tests/ui/manual_unwrap_or_default.fixed b/tests/ui/manual_unwrap_or_default.fixed index a0b707628a8..d6e736ba9cc 100644 --- a/tests/ui/manual_unwrap_or_default.fixed +++ b/tests/ui/manual_unwrap_or_default.fixed @@ -16,6 +16,16 @@ fn main() { let x: Option<Vec<String>> = None; x.unwrap_or_default(); + + // Issue #12564 + // No error as &Vec<_> doesn't implement std::default::Default + let mut map = std::collections::HashMap::from([(0, vec![0; 3]), (1, vec![1; 3]), (2, vec![2])]); + let x: &[_] = if let Some(x) = map.get(&0) { x } else { &[] }; + // Same code as above written using match. + let x: &[_] = match map.get(&0) { + Some(x) => x, + None => &[], + }; } // Issue #12531 diff --git a/tests/ui/manual_unwrap_or_default.rs b/tests/ui/manual_unwrap_or_default.rs index 1d4cca12f6c..462d5d90ee7 100644 --- a/tests/ui/manual_unwrap_or_default.rs +++ b/tests/ui/manual_unwrap_or_default.rs @@ -37,6 +37,16 @@ fn main() { } else { Vec::default() }; + + // Issue #12564 + // No error as &Vec<_> doesn't implement std::default::Default + let mut map = std::collections::HashMap::from([(0, vec![0; 3]), (1, vec![1; 3]), (2, vec![2])]); + let x: &[_] = if let Some(x) = map.get(&0) { x } else { &[] }; + // Same code as above written using match. + let x: &[_] = match map.get(&0) { + Some(x) => x, + None => &[], + }; } // Issue #12531 diff --git a/tests/ui/manual_unwrap_or_default.stderr b/tests/ui/manual_unwrap_or_default.stderr index d89212e6045..3f1da444301 100644 --- a/tests/ui/manual_unwrap_or_default.stderr +++ b/tests/ui/manual_unwrap_or_default.stderr @@ -53,7 +53,7 @@ LL | | }; | |_____^ help: replace it with: `x.unwrap_or_default()` error: match can be simplified with `.unwrap_or_default()` - --> tests/ui/manual_unwrap_or_default.rs:46:20 + --> tests/ui/manual_unwrap_or_default.rs:56:20 | LL | Some(_) => match *b { | ____________________^ |