X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=clippy_lints%2Fsrc%2Fquestion_mark.rs;h=7b6a0894e6d2fcc4ccb1c70133f5cff65078d51a;hb=ae02282ad0296d868a1e7d63d605834e311bb80f;hp=f054c6ef67d34d9ccb066552ec27f7f5f3c6073a;hpb=ac2e10a29a902c540e4a7844d630bde65bb32157;p=rust.git diff --git a/clippy_lints/src/question_mark.rs b/clippy_lints/src/question_mark.rs index f054c6ef67d..7b6a0894e6d 100644 --- a/clippy_lints/src/question_mark.rs +++ b/clippy_lints/src/question_mark.rs @@ -1,24 +1,26 @@ +use clippy_utils::diagnostics::span_lint_and_sugg; +use clippy_utils::higher; +use clippy_utils::is_lang_ctor; +use clippy_utils::source::snippet_with_applicability; +use clippy_utils::sugg::Sugg; +use clippy_utils::ty::is_type_diagnostic_item; +use clippy_utils::{eq_expr_value, path_to_local_id}; use if_chain::if_chain; use rustc_errors::Applicability; -use rustc_hir::def::{DefKind, Res}; -use rustc_hir::{def, BindingAnnotation, Block, Expr, ExprKind, MatchSource, PatKind, StmtKind}; +use rustc_hir::LangItem::{OptionNone, OptionSome}; +use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, PatKind, StmtKind}; use rustc_lint::{LateContext, LateLintPass}; use rustc_session::{declare_lint_pass, declare_tool_lint}; - -use crate::utils::paths::{OPTION, OPTION_NONE}; -use crate::utils::sugg::Sugg; -use crate::utils::{ - higher, match_def_path, match_qpath, match_type, snippet_with_applicability, span_lint_and_sugg, SpanlessEq, -}; +use rustc_span::sym; declare_clippy_lint! { - /// **What it does:** Checks for expressions that could be replaced by the question mark operator. - /// - /// **Why is this bad?** Question mark usage is more idiomatic. + /// ### What it does + /// Checks for expressions that could be replaced by the question mark operator. /// - /// **Known problems:** None + /// ### Why is this bad? + /// Question mark usage is more idiomatic. /// - /// **Example:** + /// ### Example /// ```ignore /// if option.is_none() { /// return None; @@ -47,12 +49,12 @@ impl QuestionMark { /// ``` /// /// If it matches, it will suggest to use the question mark operator instead - fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr<'_>) { + fn check_is_none_and_early_return_none(cx: &LateContext<'_>, expr: &Expr<'_>) { if_chain! { - if let Some((if_expr, body, else_)) = higher::if_block(&expr); - if let ExprKind::MethodCall(segment, _, args) = &if_expr.kind; + if let Some(higher::If { cond, then, r#else }) = higher::If::hir(expr); + if let ExprKind::MethodCall(segment, _, args, _) = &cond.kind; if segment.ident.name == sym!(is_none); - if Self::expression_returns_none(cx, body); + if Self::expression_returns_none(cx, then); if let Some(subject) = args.get(0); if Self::is_option(cx, subject); @@ -60,20 +62,22 @@ fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr<'_> let mut applicability = Applicability::MachineApplicable; let receiver_str = &Sugg::hir_with_applicability(cx, subject, "..", &mut applicability); let mut replacement: Option = None; - if let Some(else_) = else_ { + if let Some(else_inner) = r#else { if_chain! { - if let ExprKind::Block(block, None) = &else_.kind; + if let ExprKind::Block(block, None) = &else_inner.kind; if block.stmts.is_empty(); if let Some(block_expr) = &block.expr; - if SpanlessEq::new(cx).ignore_fn().eq_expr(subject, block_expr); + if eq_expr_value(cx, subject, block_expr); then { replacement = Some(format!("Some({}?)", receiver_str)); } } - } else if Self::moves_by_default(cx, subject) { - replacement = Some(format!("{}.as_ref()?;", receiver_str)); + } else if Self::moves_by_default(cx, subject) + && !matches!(subject.kind, ExprKind::Call(..) | ExprKind::MethodCall(..)) + { + replacement = Some(format!("{}.as_ref()?;", receiver_str)); } else { - replacement = Some(format!("{}?;", receiver_str)); + replacement = Some(format!("{}?;", receiver_str)); } if let Some(replacement_str) = replacement { @@ -85,34 +89,31 @@ fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr<'_> "replace it with", replacement_str, applicability, - ) - } + ); + } } } } - fn check_if_let_some_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr<'_>) { + fn check_if_let_some_and_early_return_none(cx: &LateContext<'_>, expr: &Expr<'_>) { if_chain! { - if let ExprKind::Match(subject, arms, source) = &expr.kind; - if *source == MatchSource::IfLetDesugar { contains_else_clause: true }; - if Self::is_option(cx, subject); + if let Some(higher::IfLet { let_pat, let_expr, if_then, if_else: Some(if_else) }) = higher::IfLet::hir(cx, expr); + if Self::is_option(cx, let_expr); - if let PatKind::TupleStruct(path1, fields, None) = &arms[0].pat.kind; - if match_qpath(path1, &["Some"]); - if let PatKind::Binding(annot, _, bind, _) = &fields[0].kind; + if let PatKind::TupleStruct(ref path1, fields, None) = let_pat.kind; + if is_lang_ctor(cx, path1, OptionSome); + if let PatKind::Binding(annot, bind_id, _, _) = fields[0].kind; let by_ref = matches!(annot, BindingAnnotation::Ref | BindingAnnotation::RefMut); - if let ExprKind::Block(block, None) = &arms[0].body.kind; + if let ExprKind::Block(ref block, None) = if_then.kind; if block.stmts.is_empty(); if let Some(trailing_expr) = &block.expr; - if let ExprKind::Path(path) = &trailing_expr.kind; - if match_qpath(path, &[&bind.as_str()]); + if path_to_local_id(trailing_expr, bind_id); - if let PatKind::Wild = arms[1].pat.kind; - if Self::expression_returns_none(cx, arms[1].body); + if Self::expression_returns_none(cx, if_else); then { let mut applicability = Applicability::MachineApplicable; - let receiver_str = snippet_with_applicability(cx, subject.span, "..", &mut applicability); + let receiver_str = snippet_with_applicability(cx, let_expr.span, "..", &mut applicability); let replacement = format!( "{}{}?", receiver_str, @@ -127,42 +128,34 @@ fn check_if_let_some_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr "replace it with", replacement, applicability, - ) + ); } } } - fn moves_by_default(cx: &LateContext<'_, '_>, expression: &Expr<'_>) -> bool { - let expr_ty = cx.tables.expr_ty(expression); + fn moves_by_default(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool { + let expr_ty = cx.typeck_results().expr_ty(expression); - !expr_ty.is_copy_modulo_regions(cx.tcx, cx.param_env, expression.span) + !expr_ty.is_copy_modulo_regions(cx.tcx.at(expression.span), cx.param_env) } - fn is_option(cx: &LateContext<'_, '_>, expression: &Expr<'_>) -> bool { - let expr_ty = cx.tables.expr_ty(expression); + fn is_option(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool { + let expr_ty = cx.typeck_results().expr_ty(expression); - match_type(cx, expr_ty, &OPTION) + is_type_diagnostic_item(cx, expr_ty, sym::option_type) } - fn expression_returns_none(cx: &LateContext<'_, '_>, expression: &Expr<'_>) -> bool { + fn expression_returns_none(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool { match expression.kind { - ExprKind::Block(ref block, _) => { + ExprKind::Block(block, _) => { if let Some(return_expression) = Self::return_expression(block) { - return Self::expression_returns_none(cx, &return_expression); - } - - false - }, - ExprKind::Ret(Some(ref expr)) => Self::expression_returns_none(cx, expr), - ExprKind::Path(ref qp) => { - if let Res::Def(DefKind::Ctor(def::CtorOf::Variant, def::CtorKind::Const), def_id) = - cx.tables.qpath_res(qp, expression.hir_id) - { - return match_def_path(cx, def_id, &OPTION_NONE); + return Self::expression_returns_none(cx, return_expression); } false }, + ExprKind::Ret(Some(expr)) => Self::expression_returns_none(cx, expr), + ExprKind::Path(ref qpath) => is_lang_ctor(cx, qpath, OptionNone), _ => false, } } @@ -172,9 +165,8 @@ fn return_expression<'tcx>(block: &Block<'tcx>) -> Option<&'tcx Expr<'tcx>> { if_chain! { if block.stmts.len() == 1; if let Some(expr) = block.stmts.iter().last(); - if let StmtKind::Semi(ref expr) = expr.kind; - if let ExprKind::Ret(ret_expr) = expr.kind; - if let Some(ret_expr) = ret_expr; + if let StmtKind::Semi(expr) = expr.kind; + if let ExprKind::Ret(Some(ret_expr)) = expr.kind; then { return Some(ret_expr); @@ -194,8 +186,8 @@ fn return_expression<'tcx>(block: &Block<'tcx>) -> Option<&'tcx Expr<'tcx>> { } } -impl<'a, 'tcx> LateLintPass<'a, 'tcx> for QuestionMark { - fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) { +impl<'tcx> LateLintPass<'tcx> for QuestionMark { + fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { Self::check_is_none_and_early_return_none(cx, expr); Self::check_if_let_some_and_early_return_none(cx, expr); }