use crate::utils::span_lint;
+use rustc_ast::ast::{Expr, ExprKind};
use rustc_lint::{EarlyContext, EarlyLintPass};
use rustc_session::{declare_lint_pass, declare_tool_lint};
-use syntax::ast::{Expr, ExprKind};
declare_clippy_lint! {
/// **What it does:** Checks for unnecessary double parentheses.
///
/// **Example:**
/// ```rust
+ /// // Bad
+ /// fn simple_double_parens() -> i32 {
+ /// ((0))
+ /// }
+ ///
+ /// // Good
+ /// fn simple_no_parens() -> i32 {
+ /// 0
+ /// }
+ ///
+ /// // or
+ ///
/// # fn foo(bar: usize) {}
- /// ((0));
+ /// // Bad
/// foo((0));
- /// ((1, 2));
+ ///
+ /// // Good
+ /// foo(0);
/// ```
pub DOUBLE_PARENS,
complexity,
return;
}
+ let msg: &str = "consider removing unnecessary double parentheses";
+
match expr.kind {
ExprKind::Paren(ref in_paren) => match in_paren.kind {
ExprKind::Paren(_) | ExprKind::Tup(_) => {
- span_lint(
- cx,
- DOUBLE_PARENS,
- expr.span,
- "Consider removing unnecessary double parentheses",
- );
+ span_lint(cx, DOUBLE_PARENS, expr.span, &msg);
},
_ => {},
},
if params.len() == 1 {
let param = ¶ms[0];
if let ExprKind::Paren(_) = param.kind {
- span_lint(
- cx,
- DOUBLE_PARENS,
- param.span,
- "Consider removing unnecessary double parentheses",
- );
+ span_lint(cx, DOUBLE_PARENS, param.span, &msg);
}
}
},
- ExprKind::MethodCall(_, ref params) => {
+ ExprKind::MethodCall(_, ref params, _) => {
if params.len() == 2 {
let param = ¶ms[1];
if let ExprKind::Paren(_) = param.kind {
- span_lint(
- cx,
- DOUBLE_PARENS,
- param.span,
- "Consider removing unnecessary double parentheses",
- );
+ span_lint(cx, DOUBLE_PARENS, param.span, &msg);
}
}
},