1 use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg};
2 use clippy_utils::source::snippet;
3 use clippy_utils::{is_trait_method, meets_msrv, msrvs};
4 use rustc_errors::Applicability;
6 use rustc_lint::LateContext;
7 use rustc_semver::RustcVersion;
10 use super::FILTER_MAP_NEXT;
12 pub(super) fn check<'tcx>(
13 cx: &LateContext<'tcx>,
14 expr: &'tcx hir::Expr<'_>,
15 recv: &'tcx hir::Expr<'_>,
16 arg: &'tcx hir::Expr<'_>,
17 msrv: Option<&RustcVersion>,
19 if is_trait_method(cx, expr, sym::Iterator) {
20 if !meets_msrv(msrv, &msrvs::ITERATOR_FIND_MAP) {
24 let msg = "called `filter_map(..).next()` on an `Iterator`. This is more succinctly expressed by calling \
25 `.find_map(..)` instead";
26 let filter_snippet = snippet(cx, arg.span, "..");
27 if filter_snippet.lines().count() <= 1 {
28 let iter_snippet = snippet(cx, recv.span, "..");
35 format!("{}.find_map({})", iter_snippet, filter_snippet),
36 Applicability::MachineApplicable,
39 span_lint(cx, FILTER_MAP_NEXT, expr.span, msg);