clippy_lints/src/methods/iter_skip_next.rs

   1 use clippy_utils::diagnostics::span_lint_and_sugg;
   2 use clippy_utils::is_trait_method;
   3 use clippy_utils::source::snippet;
   4 use rustc_errors::Applicability;
   5 use rustc_hir as hir;
   6 use rustc_lint::LateContext;
   7 use rustc_span::sym;
   8
   9 use super::ITER_SKIP_NEXT;
  10
  11 pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) {
  12     // lint if caller of skip is an Iterator
  13     if is_trait_method(cx, expr, sym::Iterator) {
  14         span_lint_and_sugg(
  15             cx,
  16             ITER_SKIP_NEXT,
  17             expr.span.trim_start(recv.span).unwrap(),
  18             "called `skip(..).next()` on an iterator",
  19             "use `nth` instead",
  20             format!(".nth({})", snippet(cx, arg.span, "..")),
  21             Applicability::MachineApplicable,
  22         );
  23     }
  24 }