diff --git a/clippy_lints/src/implicit_return.rs b/clippy_lints/src/implicit_return.rs index 409a10f82eb..a2a21483191 100644 --- a/clippy_lints/src/implicit_return.rs +++ b/clippy_lints/src/implicit_return.rs @@ -42,6 +42,9 @@ declare_clippy_lint! { declare_lint_pass!(ImplicitReturn => [IMPLICIT_RETURN]); +static LINT_BREAK: &str = "change `break` to `return` as shown"; +static LINT_RETURN: &str = "add `return` as shown"; + fn lint(cx: &LateContext<'_, '_>, outer_span: Span, inner_span: Span, msg: &str) { let outer_span = span_to_outer_expn(outer_span); let inner_span = span_to_outer_expn(inner_span); @@ -66,12 +69,12 @@ fn span_to_outer_expn(span: Span) -> Span { } } -fn expr_match(cx: &LateContext<'_, '_>, expr: &Expr, ret_ty_is_never: bool) { +fn expr_match(cx: &LateContext<'_, '_>, expr: &Expr) { match &expr.node { // loops could be using `break` instead of `return` ExprKind::Block(block, ..) | ExprKind::Loop(block, ..) => { if let Some(expr) = &block.expr { - expr_match(cx, expr, ret_ty_is_never); + expr_match(cx, expr); } // only needed in the case of `break` with `;` at the end else if let Some(stmt) = block.stmts.last() { @@ -81,7 +84,7 @@ fn expr_match(cx: &LateContext<'_, '_>, expr: &Expr, ret_ty_is_never: bool) { if let ExprKind::Break(.., break_expr) = &expr.node; if let Some(break_expr) = break_expr; then { - lint(cx, expr.span, break_expr.span, "change `break` to `return` as shown"); + lint(cx, expr.span, break_expr.span, LINT_BREAK); } } } @@ -89,7 +92,7 @@ fn expr_match(cx: &LateContext<'_, '_>, expr: &Expr, ret_ty_is_never: bool) { // use `return` instead of `break` ExprKind::Break(.., break_expr) => { if let Some(break_expr) = break_expr { - lint(cx, expr.span, break_expr.span, "change `break` to `return` as shown"); + lint(cx, expr.span, break_expr.span, LINT_BREAK); } }, ExprKind::Match(.., arms, source) => { @@ -102,38 +105,29 @@ fn expr_match(cx: &LateContext<'_, '_>, expr: &Expr, ret_ty_is_never: bool) { if check_all_arms { for arm in arms { - expr_match(cx, &arm.body, ret_ty_is_never); + expr_match(cx, &arm.body); } } else { - expr_match( - cx, - &arms.first().expect("if let doesn't have a single arm").body, - ret_ty_is_never, - ); + expr_match(cx, &arms.first().expect("if let doesn't have a single arm").body); } }, // skip if it already has a return statement ExprKind::Ret(..) => (), - // make sure it's not a call that panics unless we intend to return a panic + // make sure it's not a call that panics ExprKind::Call(expr, ..) => { if_chain! { if let ExprKind::Path(qpath) = &expr.node; if let Some(path_def_id) = resolve_node(cx, qpath, expr.hir_id).opt_def_id(); if match_def_path(cx, path_def_id, &BEGIN_PANIC) || match_def_path(cx, path_def_id, &BEGIN_PANIC_FMT); - then { - // only put `return` on panics if the return type of the function/closure is a panic - if ret_ty_is_never { - lint(cx, expr.span, expr.span, "add `return` as shown") - } - } + then { } else { - lint(cx, expr.span, expr.span, "add `return` as shown") + lint(cx, expr.span, expr.span, LINT_RETURN) } } }, // everything else is missing `return` - _ => lint(cx, expr.span, expr.span, "add `return` as shown"), + _ => lint(cx, expr.span, expr.span, LINT_RETURN), } } @@ -149,12 +143,11 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ImplicitReturn { ) { let def_id = cx.tcx.hir().body_owner_def_id(body.id()); let mir = cx.tcx.optimized_mir(def_id); - let ret_ty = mir.return_ty(); // checking return type through MIR, HIR is not able to determine inferred closure return types // make sure it's not a macro - if !ret_ty.is_unit() && !in_macro_or_desugar(span) { - expr_match(cx, &body.value, ret_ty.is_never()); + if !mir.return_ty().is_unit() && !in_macro_or_desugar(span) { + expr_match(cx, &body.value); } } } diff --git a/tests/ui/implicit_return.rs b/tests/ui/implicit_return.rs index ade3dc00a53..47e0679c430 100644 --- a/tests/ui/implicit_return.rs +++ b/tests/ui/implicit_return.rs @@ -77,10 +77,6 @@ fn test_closure() { let _ = || true; } -fn test_return_never() -> ! { - panic!() -} - fn test_panic() -> bool { panic!() } diff --git a/tests/ui/implicit_return.stderr b/tests/ui/implicit_return.stderr index ac6a76cd39c..41b0873317e 100644 --- a/tests/ui/implicit_return.stderr +++ b/tests/ui/implicit_return.stderr @@ -61,16 +61,10 @@ LL | let _ = || true; | ^^^^ help: add `return` as shown: `return true` error: missing return statement - --> $DIR/implicit_return.rs:81:5 - | -LL | panic!() - | ^^^^^^^^ help: add `return` as shown: `return panic!()` - -error: missing return statement - --> $DIR/implicit_return.rs:89:5 + --> $DIR/implicit_return.rs:85:5 | LL | format!("test {}", "test") | ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add `return` as shown: `return format!("test {}", "test")` -error: aborting due to 12 previous errors +error: aborting due to 11 previous errors