1 use clippy_utils::diagnostics::span_lint_and_sugg;
2 use clippy_utils::source::{indent_of, reindent_multiline, snippet_opt};
3 use clippy_utils::ty::is_type_diagnostic_item;
4 use clippy_utils::{is_res_lang_ctor, path_res, path_to_local_id};
5 use if_chain::if_chain;
6 use rustc_errors::Applicability;
7 use rustc_hir::LangItem::{ResultErr, ResultOk};
8 use rustc_hir::{Expr, ExprKind, PatKind};
9 use rustc_lint::LateContext;
10 use rustc_span::symbol::sym;
12 use super::MANUAL_OK_OR;
14 pub(super) fn check<'tcx>(
15 cx: &LateContext<'tcx>,
16 expr: &'tcx Expr<'tcx>,
18 or_expr: &'tcx Expr<'_>,
19 map_expr: &'tcx Expr<'_>,
22 if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
23 if let Some(impl_id) = cx.tcx.impl_of_method(method_id);
24 if is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Option);
25 if let ExprKind::Call(err_path, [err_arg]) = or_expr.kind;
26 if is_res_lang_ctor(cx, path_res(cx, err_path), ResultErr);
27 if is_ok_wrapping(cx, map_expr);
28 if let Some(recv_snippet) = snippet_opt(cx, recv.span);
29 if let Some(err_arg_snippet) = snippet_opt(cx, err_arg.span);
30 if let Some(indent) = indent_of(cx, expr.span);
32 let reindented_err_arg_snippet = reindent_multiline(err_arg_snippet.into(), true, Some(indent + 4));
37 "this pattern reimplements `Option::ok_or`",
40 "{recv_snippet}.ok_or({reindented_err_arg_snippet})"
42 Applicability::MachineApplicable,
48 fn is_ok_wrapping(cx: &LateContext<'_>, map_expr: &Expr<'_>) -> bool {
50 ExprKind::Path(ref qpath) if is_res_lang_ctor(cx, cx.qpath_res(qpath, map_expr.hir_id), ResultOk) => true,
51 ExprKind::Closure(closure) => {
52 let body = cx.tcx.hir().body(closure.body);
53 if let PatKind::Binding(_, param_id, ..) = body.params[0].pat.kind
54 && let ExprKind::Call(callee, [ok_arg]) = body.value.kind
55 && is_res_lang_ctor(cx, path_res(cx, callee), ResultOk)
57 path_to_local_id(ok_arg, param_id)