modify code

[rust.git] / clippy_lints / src / question_mark.rs

diff --git a/clippy_lints/src/question_mark.rs b/clippy_lints/src/question_mark.rs
index f63ef163bcbd0f1b76ddfd92fcac4d38b50a48bc..6f634ded5fef700ffcc8a08ce79fe92be7156f34 100644 (file)
--- a/clippy_lints/src/question_mark.rs
+++ b/clippy_lints/src/question_mark.rs
@@ -1,14 +1,13 @@
 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, path_to_local_id};
+use clippy_utils::{eq_expr_value, is_lang_ctor, path_to_local, path_to_local_id, peel_blocks, peel_blocks_with_stmt};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::LangItem::{OptionNone, OptionSome, ResultOk};
-use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, PatKind, StmtKind};
+use rustc_hir::{BindingAnnotation, Expr, ExprKind, PatKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::sym;
@@ -32,6 +31,7 @@
     /// ```ignore
     /// option?;
     /// ```
+    #[clippy::version = "pre 1.29.0"]
     pub QUESTION_MARK,
     style,
     "checks for expressions that could be replaced by the question mark operator"
@@ -58,7 +58,7 @@ impl QuestionMark {
     fn check_is_none_or_err_and_early_return(cx: &LateContext<'_>, expr: &Expr<'_>) {
         if_chain! {
             if let Some(higher::If { cond, then, r#else }) = higher::If::hir(expr);
-            if let ExprKind::MethodCall(segment, _, args, _) = &cond.kind;
+            if let ExprKind::MethodCall(segment, args, _) = &cond.kind;
             if let Some(subject) = args.get(0);
             if (Self::option_check_and_early_return(cx, subject, then) && segment.ident.name == sym!(is_none)) ||
                 (Self::result_check_and_early_return(cx, subject, then) && segment.ident.name == sym!(is_err));
@@ -67,14 +67,8 @@ fn check_is_none_or_err_and_early_return(cx: &LateContext<'_>, expr: &Expr<'_>)
                 let receiver_str = &Sugg::hir_with_applicability(cx, subject, "..", &mut applicability);
                 let mut replacement: Option<String> = None;
                 if let Some(else_inner) = r#else {
-                    if_chain! {
-                        if let ExprKind::Block(block, None) = &else_inner.kind;
-                        if block.stmts.is_empty();
-                        if let Some(block_expr) = &block.expr;
-                        if eq_expr_value(cx, subject, block_expr);
-                        then {
-                            replacement = Some(format!("Some({}?)", receiver_str));
-                        }
+                    if eq_expr_value(cx, subject, peel_blocks(else_inner)) {
+                        replacement = Some(format!("Some({}?)", receiver_str));
                     }
                 } else if Self::moves_by_default(cx, subject)
                     && !matches!(subject.kind, ExprKind::Call(..) | ExprKind::MethodCall(..))
@@ -109,10 +103,7 @@ fn check_if_let_some_or_err_and_early_return(cx: &LateContext<'_>, expr: &Expr<'
 
             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) = if_then.kind;
-            if block.stmts.is_empty();
-            if let Some(trailing_expr) = &block.expr;
-            if path_to_local_id(trailing_expr, bind_id);
+            if path_to_local_id(peel_blocks(if_then), bind_id);
             then {
                 let mut applicability = Applicability::MachineApplicable;
                 let receiver_str = snippet_with_applicability(cx, let_expr.span, "..", &mut applicability);
@@ -158,14 +149,7 @@ fn is_result(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool {
     }
 
     fn expression_returns_none(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool {
-        match expression.kind {
-            ExprKind::Block(block, _) => {
-                if let Some(return_expression) = Self::return_expression(block) {
-                    return Self::expression_returns_none(cx, return_expression);
-                }
-
-                false
-            },
+        match peel_blocks_with_stmt(expression).kind {
             ExprKind::Ret(Some(expr)) => Self::expression_returns_none(cx, expr),
             ExprKind::Path(ref qpath) => is_lang_ctor(cx, qpath, OptionNone),
             _ => false,
@@ -173,44 +157,12 @@ fn expression_returns_none(cx: &LateContext<'_>, expression: &Expr<'_>) -> bool
     }
 
     fn expression_returns_unmodified_err(cx: &LateContext<'_>, expr: &Expr<'_>, cond_expr: &Expr<'_>) -> bool {
-        match expr.kind {
-            ExprKind::Block(block, _) => {
-                if let Some(return_expression) = Self::return_expression(block) {
-                    return Self::expression_returns_unmodified_err(cx, return_expression, cond_expr);
-                }
-
-                false
-            },
+        match peel_blocks_with_stmt(expr).kind {
             ExprKind::Ret(Some(ret_expr)) => Self::expression_returns_unmodified_err(cx, ret_expr, cond_expr),
-            ExprKind::Path(_) => path_to_local(expr) == path_to_local(cond_expr),
+            ExprKind::Path(_) => path_to_local(expr).is_some() && path_to_local(expr) == path_to_local(cond_expr),
             _ => false,
         }
     }
-
-    fn return_expression<'tcx>(block: &Block<'tcx>) -> Option<&'tcx Expr<'tcx>> {
-        // Check if last expression is a return statement. Then, return the expression
-        if_chain! {
-            if block.stmts.len() == 1;
-            if let Some(expr) = block.stmts.iter().last();
-            if let StmtKind::Semi(expr) = expr.kind;
-            if let ExprKind::Ret(Some(ret_expr)) = expr.kind;
-
-            then {
-                return Some(ret_expr);
-            }
-        }
-
-        // Check for `return` without a semicolon.
-        if_chain! {
-            if block.stmts.is_empty();
-            if let Some(ExprKind::Ret(Some(ret_expr))) = block.expr.as_ref().map(|e| &e.kind);
-            then {
-                return Some(ret_expr);
-            }
-        }
-
-        None
-    }
 }
 
 impl<'tcx> LateLintPass<'tcx> for QuestionMark {