1 use crate::utils
::{is_type_diagnostic_item, span_lint_and_help}
;
3 use rustc_lint
::LateContext
;
6 use super::EXPECT_USED
;
8 /// lint use of `expect()` for `Option`s and `Result`s
9 pub(super) fn check(cx
: &LateContext
<'_
>, expr
: &hir
::Expr
<'_
>, expect_args
: &[hir
::Expr
<'_
>]) {
10 let obj_ty
= cx
.typeck_results().expr_ty(&expect_args
[0]).peel_refs();
12 let mess
= if is_type_diagnostic_item(cx
, obj_ty
, sym
::option_type
) {
13 Some((EXPECT_USED
, "an Option", "None"))
14 } else if is_type_diagnostic_item(cx
, obj_ty
, sym
::result_type
) {
15 Some((EXPECT_USED
, "a Result", "Err"))
20 if let Some((lint
, kind
, none_value
)) = mess
{
25 &format
!("used `expect()` on `{}` value", kind
,),
27 &format
!("if this value is an `{}`, it will panic", none_value
,),