Merge remote-tracking branch 'upstream/master' into rustup

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

diff --git a/clippy_lints/src/double_parens.rs b/clippy_lints/src/double_parens.rs
index 5afdcb3c09f592aa8261524c079d1797375d367e..29425b2e5541791db6c485d904a38981abda173b 100644 (file)
--- a/clippy_lints/src/double_parens.rs
+++ b/clippy_lints/src/double_parens.rs
@@ -4,34 +4,33 @@
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for unnecessary double parentheses.
+    /// ### What it does
+    /// Checks for unnecessary double parentheses.
     ///
-    /// **Why is this bad?** This makes code harder to read and might indicate a
+    /// ### Why is this bad?
+    /// This makes code harder to read and might indicate a
     /// mistake.
     ///
-    /// **Known problems:** None.
-    ///
-    /// **Example:**
+    /// ### Example
     /// ```rust
-    /// // Bad
     /// fn simple_double_parens() -> i32 {
     ///     ((0))
     /// }
     ///
-    /// // Good
+    /// # fn foo(bar: usize) {}
+    /// foo((0));
+    /// ```
+    ///
+    /// Use instead:
+    /// ```rust
     /// fn simple_no_parens() -> i32 {
     ///     0
     /// }
     ///
-    /// // or
-    ///
     /// # fn foo(bar: usize) {}
-    /// // Bad
-    /// foo((0));
-    ///
-    /// // Good
     /// foo(0);
     /// ```
+    #[clippy::version = "pre 1.29.0"]
     pub DOUBLE_PARENS,
     complexity,
     "Warn on unnecessary double parentheses"
@@ -50,7 +49,7 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
         match expr.kind {
             ExprKind::Paren(ref in_paren) => match in_paren.kind {
                 ExprKind::Paren(_) | ExprKind::Tup(_) => {
-                    span_lint(cx, DOUBLE_PARENS, expr.span, &msg);
+                    span_lint(cx, DOUBLE_PARENS, expr.span, msg);
                 },
                 _ => {},
             },
@@ -58,15 +57,14 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
                 if params.len() == 1 {
                     let param = &params[0];
                     if let ExprKind::Paren(_) = param.kind {
-                        span_lint(cx, DOUBLE_PARENS, param.span, &msg);
+                        span_lint(cx, DOUBLE_PARENS, param.span, msg);
                     }
                 }
             },
-            ExprKind::MethodCall(_, ref params, _) => {
-                if params.len() == 2 {
-                    let param = &params[1];
-                    if let ExprKind::Paren(_) = param.kind {
-                        span_lint(cx, DOUBLE_PARENS, param.span, &msg);
+            ExprKind::MethodCall(ref call) => {
+                if let [ref arg] = call.args[..] {
+                    if let ExprKind::Paren(_) = arg.kind {
+                        span_lint(cx, DOUBLE_PARENS, arg.span, msg);
                     }
                 }
             },