diff options
| -rw-r--r-- | clippy_lints/src/lib.rs | 3 | ||||
| -rw-r--r-- | clippy_lints/src/manual_map.rs | 210 | ||||
| -rw-r--r-- | clippy_utils/src/lib.rs | 45 | ||||
| -rw-r--r-- | tests/ui/manual_map_option.fixed | 63 | ||||
| -rw-r--r-- | tests/ui/manual_map_option.rs | 69 | ||||
| -rw-r--r-- | tests/ui/manual_map_option.stderr | 54 |
6 files changed, 348 insertions, 96 deletions
diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index 1ace4c8a10c..183778cb55e 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -1543,6 +1543,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: LintId::of(&loops::WHILE_LET_ON_ITERATOR), LintId::of(&main_recursion::MAIN_RECURSION), LintId::of(&manual_async_fn::MANUAL_ASYNC_FN), + LintId::of(&manual_map::MANUAL_MAP), LintId::of(&manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE), LintId::of(&manual_strip::MANUAL_STRIP), LintId::of(&manual_unwrap_or::MANUAL_UNWRAP_OR), @@ -1774,6 +1775,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: LintId::of(&loops::WHILE_LET_ON_ITERATOR), LintId::of(&main_recursion::MAIN_RECURSION), LintId::of(&manual_async_fn::MANUAL_ASYNC_FN), + LintId::of(&manual_map::MANUAL_MAP), LintId::of(&manual_non_exhaustive::MANUAL_NON_EXHAUSTIVE), LintId::of(&map_clone::MAP_CLONE), LintId::of(&matches::INFALLIBLE_DESTRUCTURING_MATCH), @@ -2050,7 +2052,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: LintId::of(&floating_point_arithmetic::SUBOPTIMAL_FLOPS), LintId::of(&future_not_send::FUTURE_NOT_SEND), LintId::of(&let_if_seq::USELESS_LET_IF_SEQ), - LintId::of(&manual_map::MANUAL_MAP), LintId::of(&missing_const_for_fn::MISSING_CONST_FOR_FN), LintId::of(&mutable_debug_assertion::DEBUG_ASSERT_WITH_MUT_CALL), LintId::of(&mutex_atomic::MUTEX_INTEGER), diff --git a/clippy_lints/src/manual_map.rs b/clippy_lints/src/manual_map.rs index 78dc0d54f28..ac1d51e1993 100644 --- a/clippy_lints/src/manual_map.rs +++ b/clippy_lints/src/manual_map.rs @@ -2,24 +2,32 @@ use crate::{ map_unit_fn::OPTION_MAP_UNIT_FN, matches::MATCH_AS_REF, utils::{ - is_allowed, is_type_diagnostic_item, match_def_path, match_var, paths, peel_hir_expr_refs, - peel_mid_ty_refs_is_mutable, snippet_with_applicability, span_lint_and_sugg, + can_partially_move_ty, is_allowed, is_type_diagnostic_item, match_def_path, match_var, paths, + peel_hir_expr_refs, peel_mid_ty_refs_is_mutable, snippet_with_applicability, snippet_with_context, + span_lint_and_sugg, }, }; use rustc_ast::util::parser::PREC_POSTFIX; use rustc_errors::Applicability; -use rustc_hir::{Arm, BindingAnnotation, Block, Expr, ExprKind, Mutability, Pat, PatKind, QPath}; +use rustc_hir::{ + def::Res, + intravisit::{walk_expr, ErasedMap, NestedVisitorMap, Visitor}, + Arm, BindingAnnotation, Block, Expr, ExprKind, Mutability, Pat, PatKind, Path, QPath, +}; use rustc_lint::{LateContext, LateLintPass, LintContext}; use rustc_middle::lint::in_external_macro; use rustc_session::{declare_lint_pass, declare_tool_lint}; -use rustc_span::symbol::{sym, Ident}; +use rustc_span::{ + symbol::{sym, Ident}, + SyntaxContext, +}; declare_clippy_lint! { /// **What it does:** Checks for usages of `match` which could be implemented using `map` /// /// **Why is this bad?** Using the `map` method is clearer and more concise. /// - /// **Known problems:** `map` is not capable of representing some control flow which works fine in `match`. + /// **Known problems:** None. /// /// **Example:** /// @@ -34,7 +42,7 @@ declare_clippy_lint! { /// Some(0).map(|x| x + 1); /// ``` pub MANUAL_MAP, - nursery, + style, "reimplementation of `map`" } @@ -52,43 +60,46 @@ impl LateLintPass<'_> for ManualMap { { let (scrutinee_ty, ty_ref_count, ty_mutability) = peel_mid_ty_refs_is_mutable(cx.typeck_results().expr_ty(scrutinee)); - if !is_type_diagnostic_item(cx, scrutinee_ty, sym::option_type) - || !is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::option_type) + if !(is_type_diagnostic_item(cx, scrutinee_ty, sym::option_type) + && is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::option_type)) { return; } - let (some_expr, some_pat, pat_ref_count, is_wild_none) = - match (try_parse_pattern(cx, arm1.pat), try_parse_pattern(cx, arm2.pat)) { - (Some(OptionPat::Wild), Some(OptionPat::Some { pattern, ref_count })) - if is_none_expr(cx, arm1.body) => - { - (arm2.body, pattern, ref_count, true) - }, - (Some(OptionPat::None), Some(OptionPat::Some { pattern, ref_count })) - if is_none_expr(cx, arm1.body) => - { - (arm2.body, pattern, ref_count, false) - }, - (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::Wild)) - if is_none_expr(cx, arm2.body) => - { - (arm1.body, pattern, ref_count, true) - }, - (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::None)) - if is_none_expr(cx, arm2.body) => - { - (arm1.body, pattern, ref_count, false) - }, - _ => return, - }; + let expr_ctxt = expr.span.ctxt(); + let (some_expr, some_pat, pat_ref_count, is_wild_none) = match ( + try_parse_pattern(cx, arm1.pat, expr_ctxt), + try_parse_pattern(cx, arm2.pat, expr_ctxt), + ) { + (Some(OptionPat::Wild), Some(OptionPat::Some { pattern, ref_count })) + if is_none_expr(cx, arm1.body) => + { + (arm2.body, pattern, ref_count, true) + }, + (Some(OptionPat::None), Some(OptionPat::Some { pattern, ref_count })) + if is_none_expr(cx, arm1.body) => + { + (arm2.body, pattern, ref_count, false) + }, + (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::Wild)) + if is_none_expr(cx, arm2.body) => + { + (arm1.body, pattern, ref_count, true) + }, + (Some(OptionPat::Some { pattern, ref_count }), Some(OptionPat::None)) + if is_none_expr(cx, arm2.body) => + { + (arm1.body, pattern, ref_count, false) + }, + _ => return, + }; // Top level or patterns aren't allowed in closures. if matches!(some_pat.kind, PatKind::Or(_)) { return; } - let some_expr = match get_some_expr(cx, some_expr) { + let some_expr = match get_some_expr(cx, some_expr, expr_ctxt) { Some(expr) => expr, None => return, }; @@ -99,6 +110,10 @@ impl LateLintPass<'_> for ManualMap { return; } + if !can_move_expr_to_closure(cx, some_expr) { + return; + } + // Determine which binding mode to use. let explicit_ref = some_pat.contains_explicit_ref_binding(); let binding_ref = explicit_ref.or_else(|| (ty_ref_count != pat_ref_count).then(|| ty_mutability)); @@ -111,47 +126,50 @@ impl LateLintPass<'_> for ManualMap { let mut app = Applicability::MachineApplicable; - // Remove address-of expressions from the scrutinee. `as_ref` will be called, - // the type is copyable, or the option is being passed by value. + // Remove address-of expressions from the scrutinee. Either `as_ref` will be called, or + // it's being passed by value. let scrutinee = peel_hir_expr_refs(scrutinee).0; - let scrutinee_str = snippet_with_applicability(cx, scrutinee.span, "_", &mut app); - let scrutinee_str = if expr.precedence().order() < PREC_POSTFIX { - // Parens are needed to chain method calls. - format!("({})", scrutinee_str) - } else { - scrutinee_str.into() - }; + let scrutinee_str = snippet_with_context(cx, scrutinee.span, expr_ctxt, "..", &mut app); + let scrutinee_str = + if scrutinee.span.ctxt() == expr.span.ctxt() && scrutinee.precedence().order() < PREC_POSTFIX { + format!("({})", scrutinee_str) + } else { + scrutinee_str.into() + }; let body_str = if let PatKind::Binding(annotation, _, some_binding, None) = some_pat.kind { - if let Some(func) = can_pass_as_func(cx, some_binding, some_expr) { - snippet_with_applicability(cx, func.span, "..", &mut app).into_owned() - } else { - if match_var(some_expr, some_binding.name) - && !is_allowed(cx, MATCH_AS_REF, expr.hir_id) - && binding_ref.is_some() - { - return; - } + match can_pass_as_func(cx, some_binding, some_expr) { + Some(func) if func.span.ctxt() == some_expr.span.ctxt() => { + snippet_with_applicability(cx, func.span, "..", &mut app).into_owned() + }, + _ => { + if match_var(some_expr, some_binding.name) + && !is_allowed(cx, MATCH_AS_REF, expr.hir_id) + && binding_ref.is_some() + { + return; + } - // `ref` and `ref mut` annotations were handled earlier. - let annotation = if matches!(annotation, BindingAnnotation::Mutable) { - "mut " - } else { - "" - }; - format!( - "|{}{}| {}", - annotation, - some_binding, - snippet_with_applicability(cx, some_expr.span, "..", &mut app) - ) + // `ref` and `ref mut` annotations were handled earlier. + let annotation = if matches!(annotation, BindingAnnotation::Mutable) { + "mut " + } else { + "" + }; + format!( + "|{}{}| {}", + annotation, + some_binding, + snippet_with_context(cx, some_expr.span, expr_ctxt, "..", &mut app) + ) + }, } } else if !is_wild_none && explicit_ref.is_none() { // TODO: handle explicit reference annotations. format!( "|{}| {}", - snippet_with_applicability(cx, some_pat.span, "..", &mut app), - snippet_with_applicability(cx, some_expr.span, "..", &mut app) + snippet_with_context(cx, some_pat.span, expr_ctxt, "..", &mut app), + snippet_with_context(cx, some_expr.span, expr_ctxt, "..", &mut app) ) } else { // Refutable bindings and mixed reference annotations can't be handled by `map`. @@ -171,6 +189,51 @@ impl LateLintPass<'_> for ManualMap { } } +// Checks if the expression can be moved into a closure as is. +fn can_move_expr_to_closure(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> bool { + struct V<'cx, 'tcx> { + cx: &'cx LateContext<'tcx>, + make_closure: bool, + } + impl Visitor<'tcx> for V<'_, 'tcx> { + type Map = ErasedMap<'tcx>; + fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> { + NestedVisitorMap::None + } + + fn visit_expr(&mut self, e: &'tcx Expr<'_>) { + match e.kind { + ExprKind::Break(..) + | ExprKind::Continue(_) + | ExprKind::Ret(_) + | ExprKind::Yield(..) + | ExprKind::InlineAsm(_) + | ExprKind::LlvmInlineAsm(_) => { + self.make_closure = false; + }, + // Accessing a field of a local value can only be done if the type isn't + // partially moved. + ExprKind::Field(base_expr, _) + if matches!( + base_expr.kind, + ExprKind::Path(QPath::Resolved(_, Path { res: Res::Local(_), .. })) + ) && can_partially_move_ty(self.cx, self.cx.typeck_results().expr_ty(base_expr)) => + { + // TODO: check if the local has been partially moved. Assume it has for now. + self.make_closure = false; + return; + } + _ => (), + }; + walk_expr(self, e); + } + } + + let mut v = V { cx, make_closure: true }; + v.visit_expr(expr); + v.make_closure +} + // Checks whether the expression could be passed as a function, or whether a closure is needed. // Returns the function to be passed to `map` if it exists. fn can_pass_as_func(cx: &LateContext<'tcx>, binding: Ident, expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> { @@ -198,11 +261,11 @@ enum OptionPat<'a> { // Try to parse into a recognized `Option` pattern. // i.e. `_`, `None`, `Some(..)`, or a reference to any of those. -fn try_parse_pattern(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) -> Option<OptionPat<'tcx>> { - fn f(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>, ref_count: usize) -> Option<OptionPat<'tcx>> { +fn try_parse_pattern(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>, ctxt: SyntaxContext) -> Option<OptionPat<'tcx>> { + fn f(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>, ref_count: usize, ctxt: SyntaxContext) -> Option<OptionPat<'tcx>> { match pat.kind { PatKind::Wild => Some(OptionPat::Wild), - PatKind::Ref(pat, _) => f(cx, pat, ref_count + 1), + PatKind::Ref(pat, _) => f(cx, pat, ref_count + 1, ctxt), PatKind::Path(QPath::Resolved(None, path)) if path .res @@ -215,18 +278,19 @@ fn try_parse_pattern(cx: &LateContext<'tcx>, pat: &'tcx Pat<'_>) -> Option<Optio if path .res .opt_def_id() - .map_or(false, |id| match_def_path(cx, id, &paths::OPTION_SOME)) => + .map_or(false, |id| match_def_path(cx, id, &paths::OPTION_SOME)) + && pat.span.ctxt() == ctxt => { Some(OptionPat::Some { pattern, ref_count }) }, _ => None, } } - f(cx, pat, 0) + f(cx, pat, 0, ctxt) } // Checks for an expression wrapped by the `Some` constructor. Returns the contained expression. -fn get_some_expr(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<&'tcx Expr<'tcx>> { +fn get_some_expr(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, ctxt: SyntaxContext) -> Option<&'tcx Expr<'tcx>> { // TODO: Allow more complex expressions. match expr.kind { ExprKind::Call( @@ -235,7 +299,7 @@ fn get_some_expr(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<&'tcx E .. }, [arg], - ) => { + ) if ctxt == expr.span.ctxt() => { if match_def_path(cx, path.res.opt_def_id()?, &paths::OPTION_SOME) { Some(arg) } else { @@ -249,7 +313,7 @@ fn get_some_expr(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) -> Option<&'tcx E .. }, _, - ) => get_some_expr(cx, expr), + ) => get_some_expr(cx, expr, ctxt), _ => None, } } diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs index fbcc6d8dc4f..00455d4102f 100644 --- a/clippy_utils/src/lib.rs +++ b/clippy_utils/src/lib.rs @@ -73,11 +73,11 @@ use rustc_middle::ty::subst::{GenericArg, GenericArgKind}; use rustc_middle::ty::{self, layout::IntegerExt, DefIdTree, Ty, TyCtxt, TypeFoldable}; use rustc_semver::RustcVersion; use rustc_session::Session; -use rustc_span::hygiene::{ExpnKind, MacroKind}; +use rustc_span::hygiene::{self, ExpnKind, MacroKind}; use rustc_span::source_map::original_sp; use rustc_span::sym; use rustc_span::symbol::{kw, Symbol}; -use rustc_span::{BytePos, Pos, Span, DUMMY_SP}; +use rustc_span::{BytePos, Pos, Span, SyntaxContext, DUMMY_SP}; use rustc_target::abi::Integer; use rustc_trait_selection::traits::query::normalize::AtExt; use smallvec::SmallVec; @@ -472,6 +472,18 @@ pub fn has_drop<'tcx>(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { } } +/// Checks whether a type can be partially moved. +pub fn can_partially_move_ty(cx: &LateContext<'tcx>, ty: Ty<'tcx>) -> bool { + if has_drop(cx, ty) || is_copy(cx, ty) { + return false; + } + match ty.kind() { + ty::Param(_) => false, + ty::Adt(def, subs) => def.all_fields().any(|f| !is_copy(cx, f.ty(cx.tcx, subs))), + _ => true, + } +} + /// Returns the method names and argument list of nested method call expressions that make up /// `expr`. method/span lists are sorted with the most recent call first. pub fn method_calls<'tcx>( @@ -762,6 +774,35 @@ pub fn snippet_block_with_applicability<'a, T: LintContext>( reindent_multiline(snip, true, indent) } +/// Same as `snippet_with_applicability`, but first walks the span up to the given context. This +/// will result in the macro call, rather then the expansion, if the span is from a child context. +/// If the span is not from a child context, it will be used directly instead. +/// +/// e.g. Given the expression `&vec![]`, getting a snippet from the span for `vec![]` as a HIR node +/// would result in `box []`. If given the context of the address of expression, this function will +/// correctly get a snippet of `vec![]`. +pub fn snippet_with_context( + cx: &LateContext<'_>, + span: Span, + outer: SyntaxContext, + default: &'a str, + applicability: &mut Applicability, +) -> Cow<'a, str> { + let outer_span = hygiene::walk_chain(span, outer); + let span = if outer_span.ctxt() == outer { + outer_span + } else { + // The span is from a macro argument, and the outer context is the macro using the argument + if *applicability != Applicability::Unspecified { + *applicability = Applicability::MaybeIncorrect; + } + // TODO: get the argument span. + span + }; + + snippet_with_applicability(cx, span, default, applicability) +} + /// Returns a new Span that extends the original Span to the first non-whitespace char of the first /// line. /// diff --git a/tests/ui/manual_map_option.fixed b/tests/ui/manual_map_option.fixed index 19350906758..9222aaf6c78 100644 --- a/tests/ui/manual_map_option.fixed +++ b/tests/ui/manual_map_option.fixed @@ -1,7 +1,14 @@ +// edition:2018 // run-rustfix #![warn(clippy::manual_map)] -#![allow(clippy::no_effect, clippy::map_identity, clippy::unit_arg, clippy::match_ref_pats)] +#![allow( + clippy::no_effect, + clippy::map_identity, + clippy::unit_arg, + clippy::match_ref_pats, + dead_code +)] fn main() { Some(0).map(|_| 2); @@ -67,4 +74,58 @@ fn main() { Some(Some((x, 1))) => Some(x), _ => None, }; + + // #6795 + fn f1() -> Result<(), ()> { + let _ = match Some(Ok(())) { + Some(x) => Some(x?), + None => None, + }; + Ok(()) + } + + for &x in Some(Some(true)).iter() { + let _ = match x { + Some(x) => Some(if x { continue } else { x }), + None => None, + }; + } + + // #6797 + let x1 = (Some(String::new()), 0); + let x2 = x1.0; + match x2 { + Some(x) => Some((x, x1.1)), + None => None, + }; + + struct S1 { + x: Option<String>, + y: u32, + } + impl S1 { + fn f(self) -> Option<(String, u32)> { + match self.x { + Some(x) => Some((x, self.y)), + None => None, + } + } + } + + // #6811 + Some(0).map(|x| vec![x]); + + option_env!("").map(String::from); + + // #6819 + async fn f2(x: u32) -> u32 { + x + } + + async fn f3() { + match Some(0) { + Some(x) => Some(f2(x).await), + None => None, + }; + } } diff --git a/tests/ui/manual_map_option.rs b/tests/ui/manual_map_option.rs index 8b8187db0a9..1ccb450619c 100644 --- a/tests/ui/manual_map_option.rs +++ b/tests/ui/manual_map_option.rs @@ -1,7 +1,14 @@ +// edition:2018 // run-rustfix #![warn(clippy::manual_map)] -#![allow(clippy::no_effect, clippy::map_identity, clippy::unit_arg, clippy::match_ref_pats)] +#![allow( + clippy::no_effect, + clippy::map_identity, + clippy::unit_arg, + clippy::match_ref_pats, + dead_code +)] fn main() { match Some(0) { @@ -119,4 +126,64 @@ fn main() { Some(Some((x, 1))) => Some(x), _ => None, }; + + // #6795 + fn f1() -> Result<(), ()> { + let _ = match Some(Ok(())) { + Some(x) => Some(x?), + None => None, + }; + Ok(()) + } + + for &x in Some(Some(true)).iter() { + let _ = match x { + Some(x) => Some(if x { continue } else { x }), + None => None, + }; + } + + // #6797 + let x1 = (Some(String::new()), 0); + let x2 = x1.0; + match x2 { + Some(x) => Some((x, x1.1)), + None => None, + }; + + struct S1 { + x: Option<String>, + y: u32, + } + impl S1 { + fn f(self) -> Option<(String, u32)> { + match self.x { + Some(x) => Some((x, self.y)), + None => None, + } + } + } + + // #6811 + match Some(0) { + Some(x) => Some(vec![x]), + None => None, + }; + + match option_env!("") { + Some(x) => Some(String::from(x)), + None => None, + }; + + // #6819 + async fn f2(x: u32) -> u32 { + x + } + + async fn f3() { + match Some(0) { + Some(x) => Some(f2(x).await), + None => None, + }; + } } diff --git a/tests/ui/manual_map_option.stderr b/tests/ui/manual_map_option.stderr index 210a30d05d4..d9f86eecd93 100644 --- a/tests/ui/manual_map_option.stderr +++ b/tests/ui/manual_map_option.stderr @@ -1,5 +1,5 @@ error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:7:5 + --> $DIR/manual_map_option.rs:14:5 | LL | / match Some(0) { LL | | Some(_) => Some(2), @@ -10,7 +10,7 @@ LL | | }; = note: `-D clippy::manual-map` implied by `-D warnings` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:12:5 + --> $DIR/manual_map_option.rs:19:5 | LL | / match Some(0) { LL | | Some(x) => Some(x + 1), @@ -19,7 +19,7 @@ LL | | }; | |_____^ help: try this: `Some(0).map(|x| x + 1)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:17:5 + --> $DIR/manual_map_option.rs:24:5 | LL | / match Some("") { LL | | Some(x) => Some(x.is_empty()), @@ -28,7 +28,7 @@ LL | | }; | |_____^ help: try this: `Some("").map(|x| x.is_empty())` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:22:5 + --> $DIR/manual_map_option.rs:29:5 | LL | / if let Some(x) = Some(0) { LL | | Some(!x) @@ -38,7 +38,7 @@ LL | | }; | |_____^ help: try this: `Some(0).map(|x| !x)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:29:5 + --> $DIR/manual_map_option.rs:36:5 | LL | / match Some(0) { LL | | Some(x) => { Some(std::convert::identity(x)) } @@ -47,7 +47,7 @@ LL | | }; | |_____^ help: try this: `Some(0).map(std::convert::identity)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:34:5 + --> $DIR/manual_map_option.rs:41:5 | LL | / match Some(&String::new()) { LL | | Some(x) => Some(str::len(x)), @@ -56,7 +56,7 @@ LL | | }; | |_____^ help: try this: `Some(&String::new()).map(|x| str::len(x))` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:44:5 + --> $DIR/manual_map_option.rs:51:5 | LL | / match &Some([0, 1]) { LL | | Some(x) => Some(x[0]), @@ -65,7 +65,7 @@ LL | | }; | |_____^ help: try this: `Some([0, 1]).as_ref().map(|x| x[0])` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:49:5 + --> $DIR/manual_map_option.rs:56:5 | LL | / match &Some(0) { LL | | &Some(x) => Some(x * 2), @@ -74,7 +74,7 @@ LL | | }; | |_____^ help: try this: `Some(0).map(|x| x * 2)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:54:5 + --> $DIR/manual_map_option.rs:61:5 | LL | / match Some(String::new()) { LL | | Some(ref x) => Some(x.is_empty()), @@ -83,7 +83,7 @@ LL | | }; | |_____^ help: try this: `Some(String::new()).as_ref().map(|x| x.is_empty())` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:59:5 + --> $DIR/manual_map_option.rs:66:5 | LL | / match &&Some(String::new()) { LL | | Some(x) => Some(x.len()), @@ -92,7 +92,7 @@ LL | | }; | |_____^ help: try this: `Some(String::new()).as_ref().map(|x| x.len())` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:64:5 + --> $DIR/manual_map_option.rs:71:5 | LL | / match &&Some(0) { LL | | &&Some(x) => Some(x + x), @@ -101,7 +101,7 @@ LL | | }; | |_____^ help: try this: `Some(0).map(|x| x + x)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:77:9 + --> $DIR/manual_map_option.rs:84:9 | LL | / match &mut Some(String::new()) { LL | | Some(x) => Some(x.push_str("")), @@ -110,7 +110,7 @@ LL | | }; | |_________^ help: try this: `Some(String::new()).as_mut().map(|x| x.push_str(""))` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:83:5 + --> $DIR/manual_map_option.rs:90:5 | LL | / match &mut Some(String::new()) { LL | | Some(ref x) => Some(x.len()), @@ -119,7 +119,7 @@ LL | | }; | |_____^ help: try this: `Some(String::new()).as_ref().map(|x| x.len())` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:88:5 + --> $DIR/manual_map_option.rs:95:5 | LL | / match &mut &Some(String::new()) { LL | | Some(x) => Some(x.is_empty()), @@ -128,7 +128,7 @@ LL | | }; | |_____^ help: try this: `Some(String::new()).as_ref().map(|x| x.is_empty())` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:93:5 + --> $DIR/manual_map_option.rs:100:5 | LL | / match Some((0, 1, 2)) { LL | | Some((x, y, z)) => Some(x + y + z), @@ -137,7 +137,7 @@ LL | | }; | |_____^ help: try this: `Some((0, 1, 2)).map(|(x, y, z)| x + y + z)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:98:5 + --> $DIR/manual_map_option.rs:105:5 | LL | / match Some([1, 2, 3]) { LL | | Some([first, ..]) => Some(first), @@ -146,7 +146,7 @@ LL | | }; | |_____^ help: try this: `Some([1, 2, 3]).map(|[first, ..]| first)` error: manual implementation of `Option::map` - --> $DIR/manual_map_option.rs:103:5 + --> $DIR/manual_map_option.rs:110:5 | LL | / match &Some((String::new(), "test")) { LL | | Some((x, y)) => Some((y, x)), @@ -154,5 +154,23 @@ LL | | None => None, LL | | }; | |_____^ help: try this: `Some((String::new(), "test")).as_ref().map(|(x, y)| (y, x))` -error: aborting due to 17 previous errors +error: manual implementation of `Option::map` + --> $DIR/manual_map_option.rs:168:5 + | +LL | / match Some(0) { +LL | | Some(x) => Some(vec![x]), +LL | | None => None, +LL | | }; + | |_____^ help: try this: `Some(0).map(|x| vec![x])` + +error: manual implementation of `Option::map` + --> $DIR/manual_map_option.rs:173:5 + | +LL | / match option_env!("") { +LL | | Some(x) => Some(String::from(x)), +LL | | None => None, +LL | | }; + | |_____^ help: try this: `option_env!("").map(String::from)` + +error: aborting due to 19 previous errors |