3 #![warn(clippy::explicit_auto_deref)]
8 clippy::needless_borrow,
9 clippy::needless_return,
11 clippy::redundant_field_names,
12 clippy::too_many_arguments,
13 clippy::borrow_deref_ref,
14 clippy::let_unit_value
19 fn callable_str(&self) -> Self::T;
21 impl CallableStr for () {
23 fn callable_str(&self) -> Self::T {
28 impl CallableStr for i32 {
29 type T = <() as CallableStr>::T;
30 fn callable_str(&self) -> Self::T {
35 trait CallableT<U: ?Sized> {
37 fn callable_t(&self) -> Self::T;
39 impl<U: ?Sized> CallableT<U> for () {
41 fn callable_t(&self) -> Self::T {
42 fn f<U: ?Sized>(_: &U) {}
46 impl<U: ?Sized> CallableT<U> for i32 {
47 type T = <() as CallableT<U>>::T;
48 fn callable_t(&self) -> Self::T {
54 fn f_string(_: &String) {}
56 fn f_ref_t<T: ?Sized>(_: &T) {}
58 fn f_str_t<T>(_: &str, _: T) {}
60 fn f_box_t<T>(_: &Box<T>) {}
63 let s = String::new();
66 let _ = &*s; // Don't lint. Inferred type would change.
67 let _: &_ = &*s; // Don't lint. Inferred type would change.
70 f_t(&*s); // Don't lint. Inferred type would change.
71 f_ref_t(&*s); // Don't lint. Inferred type would change.
73 f_str_t(&*s, &*s); // Don't lint second param.
75 let b = Box::new(Box::new(Box::new(5)));
76 let _: &Box<i32> = &**b;
77 let _: &Box<_> = &**b; // Don't lint. Inferred type would change.
79 f_box_t(&**b); // Don't lint. Inferred type would change.
81 let c = |_x: &str| ();
85 c(&*s); // Don't lint. Inferred type would change.
87 fn _f(x: &String) -> &str {
91 fn _f1(x: &String) -> &str {
95 fn _f2(x: &String) -> &str {
99 fn _f3(x: &Box<Box<Box<i32>>>) -> &Box<i32> {
108 f4: impl CallableStr,
109 f5: <() as CallableStr>::T,
110 f6: <i32 as CallableStr>::T,
111 f7: &dyn CallableStr<T = fn(&str)>,
112 f8: impl CallableT<str>,
113 f9: <() as CallableT<str>>::T,
114 f10: <i32 as CallableT<str>>::T,
115 f11: &dyn CallableT<str, T = fn(&str)>,
120 f4.callable_str()(&*x);
123 f7.callable_str()(&*x);
124 f8.callable_t()(&*x);
127 f11.callable_t()(&*x);
130 struct S1<'a>(&'a str);
136 let _ = S2 { s: &*s };
138 struct S3<'a, T: ?Sized>(&'a T);
139 let _ = S3(&*s); // Don't lint. Inferred type would change.
141 struct S4<'a, T: ?Sized> {
144 let _ = S4 { s: &*s }; // Don't lint. Inferred type would change.
151 fn m1(s: &'a String) {
152 let _ = Self::S1(&**s);
153 let _ = Self::S2 { s: &**s };
157 let _ = E1::S2 { s: &*s };
159 enum E2<'a, T: ?Sized> {
163 let _ = E2::S1(&*s); // Don't lint. Inferred type would change.
164 let _ = E2::S2 { s: &*s }; // Don't lint. Inferred type would change.
167 let _: &String = &*ref_s; // Don't lint reborrow.
168 f_string(&*ref_s); // Don't lint reborrow.
173 let b = Box::new(Box::new(S5 { foo: 5 }));
181 impl core::ops::Deref for S6 {
183 fn deref(&self) -> &Self::Target {
187 let s6 = S6 { foo: S5 { foo: 5 } };
188 let _ = (*s6).foo; // Don't lint. `S6` also has a field named `foo`
190 let ref_str = &"foo";
191 let _ = f_str(*ref_str);
192 let ref_ref_str = &ref_str;
193 let _ = f_str(**ref_ref_str);
195 fn _f5(x: &u32) -> u32 {
203 f_str(&&*ref_str); // `needless_borrow` will suggest removing both references
204 f_str(&&**ref_str); // `needless_borrow` will suggest removing only one reference