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1#![allow(unused)]
2#![warn(clippy::let_and_return)]
3
4fn test() -> i32 {
5 let _y = 0; // no warning
6 let x = 5;
7 x
8}
9
10fn test_inner() -> i32 {
11 if true {
12 let x = 5;
13 x
14 } else {
15 0
16 }
17}
18
19fn test_nowarn_1() -> i32 {
20 let mut x = 5;
21 x += 1;
22 x
23}
24
25fn test_nowarn_2() -> i32 {
26 let x = 5;
27 x + 1
28}
29
30fn test_nowarn_3() -> (i32, i32) {
31 // this should technically warn, but we do not compare complex patterns
32 let (x, y) = (5, 9);
33 (x, y)
34}
35
36fn test_nowarn_4() -> i32 {
37 // this should technically warn, but not b/c of clippy::let_and_return, but b/c of useless type
38 let x: i32 = 5;
39 x
40}
41
42fn test_nowarn_5(x: i16) -> u16 {
43 #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
44 let x = x as u16;
45 x
46}
47
48// False positive example
49trait Decode {
50 fn decode<D: std::io::Read>(d: D) -> Result<Self, ()>
51 where
52 Self: Sized;
53}
54
55macro_rules! tuple_encode {
56 ($($x:ident),*) => (
57 impl<$($x: Decode),*> Decode for ($($x),*) {
58 #[inline]
59 #[allow(non_snake_case)]
60 fn decode<D: std::io::Read>(mut d: D) -> Result<Self, ()> {
61 // Shouldn't trigger lint
62 Ok(($({let $x = Decode::decode(&mut d)?; $x }),*))
63 }
64 }
65 );
66}
67
68tuple_encode!(T0, T1, T2, T3, T4, T5, T6, T7);
69
70mod no_lint_if_stmt_borrows {
71 mod issue_3792 {
72 use std::io::{self, BufRead, Stdin};
73
74 fn read_line() -> String {
75 let stdin = io::stdin();
76 let line = stdin.lock().lines().next().unwrap().unwrap();
77 line
78 }
79 }
80
81 mod issue_3324 {
82 use std::cell::RefCell;
83 use std::rc::{Rc, Weak};
84
85 fn test(value: Weak<RefCell<Bar>>) -> u32 {
86 let value = value.upgrade().unwrap();
87 let ret = value.borrow().baz();
88 ret
89 }
90
91 struct Bar {}
92
93 impl Bar {
94 fn new() -> Self {
95 Bar {}
96 }
97 fn baz(&self) -> u32 {
98 0
99 }
100 }
101
102 fn main() {
103 let a = Rc::new(RefCell::new(Bar::new()));
104 let b = Rc::downgrade(&a);
105 test(b);
106 }
107 }
108
109 mod free_function {
110 struct Inner;
111
112 struct Foo<'a> {
113 inner: &'a Inner,
114 }
115
116 impl Drop for Foo<'_> {
117 fn drop(&mut self) {}
118 }
119
120 impl<'a> Foo<'a> {
121 fn new(inner: &'a Inner) -> Self {
122 Self { inner }
123 }
124
125 fn value(&self) -> i32 {
126 42
127 }
128 }
129
130 fn some_foo(inner: &Inner) -> Foo<'_> {
131 Foo { inner }
132 }
133
134 fn test() -> i32 {
135 let x = Inner {};
136 let value = some_foo(&x).value();
137 value
138 }
139
140 fn test2() -> i32 {
141 let x = Inner {};
142 let value = Foo::new(&x).value();
143 value
144 }
145 }
146}
147
148mod issue_5729 {
149 use std::sync::Arc;
150
151 trait Foo {}
152
153 trait FooStorage {
154 fn foo_cloned(&self) -> Arc<dyn Foo>;
155 }
156
157 struct FooStorageImpl<T: Foo> {
158 foo: Arc<T>,
159 }
160
161 impl<T: Foo + 'static> FooStorage for FooStorageImpl<T> {
162 fn foo_cloned(&self) -> Arc<dyn Foo> {
163 let clone = Arc::clone(&self.foo);
164 clone
165 }
166 }
167}
168
169fn main() {}