use utils::{span_lint, snippet};
-/// **What it does:** This lint checks for operations where precedence may be unclear and `Warn`'s about them by default, suggesting to add parentheses. Currently it catches the following:
+/// **What it does:** This lint checks for operations where precedence may be unclear and `Warn`s about them by default, suggesting to add parentheses. Currently it catches the following:
/// * mixed usage of arithmetic and bit shifting/combining operators without parentheses
/// * a "negative" numeric literal (which is really a unary `-` followed by a numeric literal) followed by a method call
///
if let ExprBinary(Spanned { node: op, ..}, ref left, ref right) = expr.node {
if !is_bit_op(op) { return; }
match (is_arith_expr(left), is_arith_expr(right)) {
- (true, true) => span_lint(cx, PRECEDENCE, expr.span,
+ (true, true) => {
+ span_lint(cx, PRECEDENCE, expr.span,
&format!("operator precedence can trip the unwary. \
Consider parenthesizing your expression:\
`({}) {} ({})`", snippet(cx, left.span, ".."),
- op.to_string(), snippet(cx, right.span, ".."))),
- (true, false) => span_lint(cx, PRECEDENCE, expr.span,
+ op.to_string(), snippet(cx, right.span, "..")));
+ },
+ (true, false) => {
+ span_lint(cx, PRECEDENCE, expr.span,
&format!("operator precedence can trip the unwary. \
Consider parenthesizing your expression:\
`({}) {} {}`", snippet(cx, left.span, ".."),
- op.to_string(), snippet(cx, right.span, ".."))),
- (false, true) => span_lint(cx, PRECEDENCE, expr.span,
+ op.to_string(), snippet(cx, right.span, "..")));
+ },
+ (false, true) => {
+ span_lint(cx, PRECEDENCE, expr.span,
&format!("operator precedence can trip the unwary. \
Consider parenthesizing your expression:\
`{} {} ({})`", snippet(cx, left.span, ".."),
- op.to_string(), snippet(cx, right.span, ".."))),
+ op.to_string(), snippet(cx, right.span, "..")));
+ },
_ => (),
}
}
if let Some(slf) = args.first() {
if let ExprLit(ref lit) = slf.node {
match lit.node {
- LitInt(..) | LitFloat(..) | LitFloatUnsuffixed(..) =>
+ LitInt(..) | LitFloat(..) | LitFloatUnsuffixed(..) => {
span_lint(cx, PRECEDENCE, expr.span, &format!(
"unary minus has lower precedence than \
method call. Consider adding parentheses \
to clarify your intent: -({})",
- snippet(cx, rhs.span, ".."))),
+ snippet(cx, rhs.span, "..")));
+ }
_ => ()
}
}