Auto merge of #3680 - g-bartoszek:needless-bool-else-if-brackets, r=oli-obk

[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 057b4850e4f4ad0d7c082348c0480d5da5cd51a5..03f6ea12e0012ac961501c1c202e7b34955ae9b3 100644 (file)
--- a/clippy_lints/src/question_mark.rs
+++ b/clippy_lints/src/question_mark.rs
@@ -1,23 +1,14 @@
-// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use crate::rustc::hir::def::Def;
-use crate::rustc::hir::*;
-use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use crate::rustc::{declare_tool_lint, lint_array};
-use crate::syntax::ptr::P;
 use crate::utils::sugg::Sugg;
 use if_chain::if_chain;
+use rustc::hir::def::Def;
+use rustc::hir::*;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::{declare_tool_lint, lint_array};
+use syntax::ptr::P;
 
-use crate::rustc_errors::Applicability;
 use crate::utils::paths::*;
 use crate::utils::{match_def_path, match_type, span_lint_and_then, SpanlessEq};
+use rustc_errors::Applicability;
 
 /// **What it does:** Checks for expressions that could be replaced by the question mark operator
 ///
@@ -72,6 +63,8 @@ fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr) {
             if Self::is_option(cx, subject);
 
             then {
+                let receiver_str = &Sugg::hir(cx, subject, "..");
+                let mut replacement: Option<String> = None;
                 if let Some(else_) = else_ {
                     if_chain! {
                         if let ExprKind::Block(block, None) = &else_.node;
@@ -79,45 +72,41 @@ fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr) {
                         if let Some(block_expr) = &block.expr;
                         if SpanlessEq::new(cx).ignore_fn().eq_expr(subject, block_expr);
                         then {
-                            span_lint_and_then(
-                                cx,
-                                QUESTION_MARK,
-                                expr.span,
-                                "this block may be rewritten with the `?` operator",
-                                |db| {
-                                    db.span_suggestion_with_applicability(
-                                        expr.span,
-                                        "replace_it_with",
-                                        format!("Some({}?)", Sugg::hir(cx, subject, "..")),
-                                        Applicability::MaybeIncorrect, // snippet
-                                    );
-                                }
-                            )
+                            replacement = Some(format!("Some({}?)", receiver_str));
                         }
                     }
-                    return;
+                } else if Self::moves_by_default(cx, subject) {
+                        replacement = Some(format!("{}.as_ref()?;", receiver_str));
+                } else {
+                        replacement = Some(format!("{}?;", receiver_str));
                 }
 
-                span_lint_and_then(
-                    cx,
-                    QUESTION_MARK,
-                    expr.span,
-                    "this block may be rewritten with the `?` operator",
-                    |db| {
-                        let receiver_str = &Sugg::hir(cx, subject, "..");
-
-                        db.span_suggestion_with_applicability(
-                            expr.span,
-                            "replace_it_with",
-                            format!("{}?;", receiver_str),
-                            Applicability::MaybeIncorrect, // snippet
-                        );
-                    }
-                )
+                if let Some(replacement_str) = replacement {
+                    span_lint_and_then(
+                        cx,
+                        QUESTION_MARK,
+                        expr.span,
+                        "this block may be rewritten with the `?` operator",
+                        |db| {
+                            db.span_suggestion_with_applicability(
+                                expr.span,
+                                "replace_it_with",
+                                replacement_str,
+                                Applicability::MaybeIncorrect, // snippet
+                            );
+                        }
+                    )
+               }
             }
         }
     }
 
+    fn moves_by_default(cx: &LateContext<'_, '_>, expression: &Expr) -> bool {
+        let expr_ty = cx.tables.expr_ty(expression);
+
+        !expr_ty.is_copy_modulo_regions(cx.tcx, cx.param_env, expression.span)
+    }
+
     fn is_option(cx: &LateContext<'_, '_>, expression: &Expr) -> bool {
         let expr_ty = cx.tables.expr_ty(expression);
 
@@ -150,7 +139,7 @@ fn return_expression(block: &Block) -> Option<P<Expr>> {
         if_chain! {
             if block.stmts.len() == 1;
             if let Some(expr) = block.stmts.iter().last();
-            if let StmtKind::Semi(ref expr, _) = expr.node;
+            if let StmtKind::Semi(ref expr) = expr.node;
             if let ExprKind::Ret(ref ret_expr) = expr.node;
             if let &Some(ref ret_expr) = ret_expr;