1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
//@run-rustfix
#![allow(unused)]
#![warn(clippy::manual_while_let_some)]
struct VecInStruct {
numbers: Vec<i32>,
unrelated: String,
}
struct Foo {
a: i32,
b: i32,
}
fn accept_i32(_: i32) {}
fn accept_optional_i32(_: Option<i32>) {}
fn accept_i32_tuple(_: (i32, i32)) {}
fn main() {
let mut numbers = vec![1, 2, 3, 4, 5];
while let Some(number) = numbers.pop() {
}
let mut val = VecInStruct {
numbers: vec![1, 2, 3, 4, 5],
unrelated: String::new(),
};
while let Some(number) = val.numbers.pop() {
}
while let Some(element) = numbers.pop() {
accept_i32(element);
}
while let Some(element) = numbers.pop() {
accept_i32(element);
}
// This should not warn. It "conditionally" pops elements.
while !numbers.is_empty() {
if true {
accept_i32(numbers.pop().unwrap());
}
}
// This should also not warn. It conditionally pops elements.
while !numbers.is_empty() {
if false {
continue;
}
accept_i32(numbers.pop().unwrap());
}
// This should not warn. It pops elements, but does not unwrap it.
// Might handle the Option in some other arbitrary way.
while !numbers.is_empty() {
accept_optional_i32(numbers.pop());
}
let unrelated_vec: Vec<String> = Vec::new();
// This should not warn. It pops elements from a different vector.
while !unrelated_vec.is_empty() {
accept_i32(numbers.pop().unwrap());
}
macro_rules! generate_loop {
() => {
while !numbers.is_empty() {
accept_i32(numbers.pop().unwrap());
}
};
}
// Do not warn if the loop comes from a macro.
generate_loop!();
// Try other kinds of patterns
let mut numbers = vec![(0, 0), (1, 1), (2, 2)];
while let Some((a, b)) = numbers.pop() {
}
while let Some(element) = numbers.pop() {
accept_i32_tuple(element);
}
let mut results = vec![Foo { a: 1, b: 2 }, Foo { a: 3, b: 4 }];
while let Some(Foo { a, b }) = results.pop() {
}
}
|
