-use crate::utils::{higher, in_macro, match_qpath, span_lint_and_sugg, SpanlessEq};
+use crate::utils::{in_macro, match_qpath, span_lint_and_sugg, SpanlessEq};
use if_chain::if_chain;
use rustc_ast::ast::LitKind;
use rustc_errors::Applicability;
/// if i != 0 {
/// i -= 1;
/// }
- /// ```
- /// Use instead:
- /// ```rust
- /// let end: u32 = 10;
- /// let start: u32 = 5;
- ///
- /// let mut i: u32 = end - start;
///
/// // Good
/// i = i.saturating_sub(1);
declare_lint_pass!(ImplicitSaturatingSub => [IMPLICIT_SATURATING_SUB]);
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ImplicitSaturatingSub {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'tcx>) {
+impl<'tcx> LateLintPass<'tcx> for ImplicitSaturatingSub {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
if in_macro(expr.span) {
return;
}
if_chain! {
- if let Some((ref cond, ref then, None)) = higher::if_block(&expr);
+ if let ExprKind::If(cond, then, None) = &expr.kind;
// Check if the conditional expression is a binary operation
if let ExprKind::Binary(ref cond_op, ref cond_left, ref cond_right) = cond.kind;
if let Some(target) = subtracts_one(cx, e);
// Extracting out the variable name
- if let ExprKind::Path(ref assign_path) = target.kind;
- if let QPath::Resolved(_, ref ares_path) = assign_path;
+ if let ExprKind::Path(QPath::Resolved(_, ref ares_path)) = target.kind;
then {
// Handle symmetric conditions in the if statement
};
// Check if the variable in the condition statement is an integer
- if !cx.tables.expr_ty(cond_var).is_integral() {
+ if !cx.typeck_results().expr_ty(cond_var).is_integral() {
return;
}
ExprKind::Lit(ref cond_lit) => {
// Check if the constant is zero
if let LitKind::Int(0, _) = cond_lit.node {
- if cx.tables.expr_ty(cond_left).is_signed() {
+ if cx.typeck_results().expr_ty(cond_left).is_signed() {
} else {
print_lint_and_sugg(cx, &var_name, expr);
};
}
}
-fn subtracts_one<'a>(cx: &LateContext<'_, '_>, expr: &Expr<'a>) -> Option<&'a Expr<'a>> {
+fn subtracts_one<'a>(cx: &LateContext<'_>, expr: &Expr<'a>) -> Option<&'a Expr<'a>> {
match expr.kind {
ExprKind::AssignOp(ref op1, ref target, ref value) => {
if_chain! {
}
}
-fn print_lint_and_sugg(cx: &LateContext<'_, '_>, var_name: &str, expr: &Expr<'_>) {
+fn print_lint_and_sugg(cx: &LateContext<'_>, var_name: &str, expr: &Expr<'_>) {
span_lint_and_sugg(
cx,
IMPLICIT_SATURATING_SUB,
expr.span,
- "Implicitly performing saturating subtraction",
+ "implicitly performing saturating subtraction",
"try",
- format!("{} = {}.saturating_sub({});", var_name, var_name, 1.to_string()),
+ format!("{} = {}.saturating_sub({});", var_name, var_name, '1'),
Applicability::MachineApplicable,
);
}