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>) {}
67 let s = String::new();
70 let _: &str = &*{ String::new() };
71 let _: &str = &mut *{ String::new() };
72 let _ = &*s; // Don't lint. Inferred type would change.
73 let _: &_ = &*s; // Don't lint. Inferred type would change.
76 f_t(&*s); // Don't lint. Inferred type would change.
77 f_ref_t(&*s); // Don't lint. Inferred type would change.
79 f_str_t(&*s, &*s); // Don't lint second param.
81 let b = Box::new(Box::new(Box::new(5)));
82 let _: &Box<i32> = &**b;
83 let _: &Box<_> = &**b; // Don't lint. Inferred type would change.
85 f_box_t(&**b); // Don't lint. Inferred type would change.
87 let c = |_x: &str| ();
91 c(&*s); // Don't lint. Inferred type would change.
93 fn _f(x: &String) -> &str {
97 fn _f1(x: &String) -> &str {
101 fn _f2(x: &String) -> &str {
105 fn _f3(x: &Box<Box<Box<i32>>>) -> &Box<i32> {
114 f4: impl CallableStr,
115 f5: <() as CallableStr>::T,
116 f6: <i32 as CallableStr>::T,
117 f7: &dyn CallableStr<T = fn(&str)>,
118 f8: impl CallableT<str>,
119 f9: <() as CallableT<str>>::T,
120 f10: <i32 as CallableT<str>>::T,
121 f11: &dyn CallableT<str, T = fn(&str)>,
126 f4.callable_str()(&*x);
129 f7.callable_str()(&*x);
130 f8.callable_t()(&*x);
133 f11.callable_t()(&*x);
136 struct S1<'a>(&'a str);
142 let _ = S2 { s: &*s };
144 struct S3<'a, T: ?Sized>(&'a T);
145 let _ = S3(&*s); // Don't lint. Inferred type would change.
147 struct S4<'a, T: ?Sized> {
150 let _ = S4 { s: &*s }; // Don't lint. Inferred type would change.
157 fn m1(s: &'a String) {
158 let _ = Self::S1(&**s);
159 let _ = Self::S2 { s: &**s };
163 let _ = E1::S2 { s: &*s };
165 enum E2<'a, T: ?Sized> {
169 let _ = E2::S1(&*s); // Don't lint. Inferred type would change.
170 let _ = E2::S2 { s: &*s }; // Don't lint. Inferred type would change.
173 let _: &String = &*ref_s; // Don't lint reborrow.
174 f_string(&*ref_s); // Don't lint reborrow.
179 let b = Box::new(Box::new(S5 { foo: 5 }));
187 impl core::ops::Deref for S6 {
189 fn deref(&self) -> &Self::Target {
193 let s6 = S6 { foo: S5 { foo: 5 } };
194 let _ = (*s6).foo; // Don't lint. `S6` also has a field named `foo`
196 let ref_str = &"foo";
197 let _ = f_str(*ref_str);
198 let ref_ref_str = &ref_str;
199 let _ = f_str(**ref_ref_str);
201 fn _f5(x: &u32) -> u32 {
209 f_str(&&*ref_str); // `needless_borrow` will suggest removing both references
210 f_str(&&**ref_str); // `needless_borrow` will suggest removing only one reference
218 let _ = || return *s;
219 let _ = || -> &'static str { return *s };
223 impl core::ops::Deref for Y {
225 fn deref(&self) -> &Self::Target {
229 let _: &X = &*{ Y(X) };
230 let _: &X = &*match 0 {
235 let _: &X = &*if true { Y(X) } else { panic!() };
237 fn deref_to_u<U, T: core::ops::Deref<Target = U>>(x: &T) -> &U {
241 let _ = |x: &'static Box<dyn Iterator<Item = u32>>| -> &'static dyn Iterator<Item = u32> { &**x };
242 fn ret_any(x: &Box<dyn std::any::Any>) -> &dyn std::any::Any {