//! lint on if branches that could be swapped so no `!` operation is necessary
//! on the condition
-use rustc::lint::*;
+use rustc::declare_lint_pass;
+use rustc::lint::{in_external_macro, EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass};
+use rustc_session::declare_tool_lint;
use syntax::ast::*;
-use utils::{in_external_macro, span_help_and_lint};
+use crate::utils::span_help_and_lint;
-/// **What it does:** Checks for usage of `!` or `!=` in an if condition with an
-/// else branch.
-///
-/// **Why is this bad?** Negations reduce the readability of statements.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// if !v.is_empty() {
-/// a()
-/// } else {
-/// b()
-/// }
-/// ```
-///
-/// Could be written:
-///
-/// ```rust
-/// if v.is_empty() {
-/// b()
-/// } else {
-/// a()
-/// }
-/// ```
-declare_lint! {
+declare_clippy_lint! {
+ /// **What it does:** Checks for usage of `!` or `!=` in an if condition with an
+ /// else branch.
+ ///
+ /// **Why is this bad?** Negations reduce the readability of statements.
+ ///
+ /// **Known problems:** None.
+ ///
+ /// **Example:**
+ /// ```rust
+ /// # let v: Vec<usize> = vec![];
+ /// # fn a() {}
+ /// # fn b() {}
+ /// if !v.is_empty() {
+ /// a()
+ /// } else {
+ /// b()
+ /// }
+ /// ```
+ ///
+ /// Could be written:
+ ///
+ /// ```rust
+ /// # let v: Vec<usize> = vec![];
+ /// # fn a() {}
+ /// # fn b() {}
+ /// if v.is_empty() {
+ /// b()
+ /// } else {
+ /// a()
+ /// }
+ /// ```
pub IF_NOT_ELSE,
- Allow,
+ pedantic,
"`if` branches that could be swapped so no negation operation is necessary on the condition"
}
-pub struct IfNotElse;
-
-impl LintPass for IfNotElse {
- fn get_lints(&self) -> LintArray {
- lint_array!(IF_NOT_ELSE)
- }
-}
+declare_lint_pass!(IfNotElse => [IF_NOT_ELSE]);
impl EarlyLintPass for IfNotElse {
- fn check_expr(&mut self, cx: &EarlyContext, item: &Expr) {
- if in_external_macro(cx, item.span) {
+ fn check_expr(&mut self, cx: &EarlyContext<'_>, item: &Expr) {
+ if in_external_macro(cx.sess(), item.span) {
return;
}
- if let ExprKind::If(ref cond, _, Some(ref els)) = item.node {
- if let ExprKind::Block(..) = els.node {
- match cond.node {
+ if let ExprKind::If(ref cond, _, Some(ref els)) = item.kind {
+ if let ExprKind::Block(..) = els.kind {
+ match cond.kind {
ExprKind::Unary(UnOp::Not, _) => {
span_help_and_lint(
cx,