src/tools/clippy/clippy_lints/src/loops/explicit_into_iter_loop.rs

   1 use super::EXPLICIT_INTO_ITER_LOOP;
   2 use clippy_utils::diagnostics::span_lint_and_sugg;
   3 use clippy_utils::source::snippet_with_applicability;
   4 use clippy_utils::{match_trait_method, paths};
   5 use rustc_errors::Applicability;
   6 use rustc_hir::Expr;
   7 use rustc_lint::LateContext;
   8 use rustc_middle::ty::TyS;
   9
  10 pub(super) fn check(cx: &LateContext<'_>, self_arg: &'hir Expr<'hir>, call_expr: &Expr<'_>) {
  11     let self_ty = cx.typeck_results().expr_ty(self_arg);
  12     let self_ty_adjusted = cx.typeck_results().expr_ty_adjusted(self_arg);
  13     if !(TyS::same_type(self_ty, self_ty_adjusted) && match_trait_method(cx, call_expr, &paths::INTO_ITERATOR)) {
  14         return;
  15     }
  16
  17     let mut applicability = Applicability::MachineApplicable;
  18     let object = snippet_with_applicability(cx, self_arg.span, "_", &mut applicability);
  19     span_lint_and_sugg(
  20         cx,
  21         EXPLICIT_INTO_ITER_LOOP,
  22         call_expr.span,
  23         "it is more concise to loop over containers instead of using explicit \
  24             iteration methods",
  25         "to write this more concisely, try",
  26         object.to_string(),
  27         applicability,
  28     );
  29 }