1// run-rustfix
2
3#![deny(clippy::useless_conversion)]
4#![allow(clippy::unnecessary_wraps)]
5
6fn test_generic<T: Copy>(val: T) -> T {
7    let _ = val;
8    val
9}
10
11fn test_generic2<T: Copy + Into<i32> + Into<U>, U: From<T>>(val: T) {
12    // ok
13    let _: i32 = val.into();
14    let _: U = val.into();
15    let _ = U::from(val);
16}
17
18fn test_questionmark() -> Result<(), ()> {
19    {
20        let _: i32 = 0i32;
21        Ok(Ok(()))
22    }??;
23    Ok(())
24}
25
26fn test_issue_3913() -> Result<(), std::io::Error> {
27    use std::fs;
28    use std::path::Path;
29
30    let path = Path::new(".");
31    for _ in fs::read_dir(path)? {}
32
33    Ok(())
34}
35
36fn test_issue_5833() -> Result<(), ()> {
37    let text = "foo\r\nbar\n\nbaz\n";
38    let lines = text.lines();
39    if Some("ok") == lines.into_iter().next() {}
40
41    Ok(())
42}
43
44fn main() {
45    test_generic(10i32);
46    test_generic2::<i32, i32>(10i32);
47    test_questionmark().unwrap();
48    test_issue_3913().unwrap();
49    test_issue_5833().unwrap();
50
51    let _: String = "foo".into();
52    let _: String = From::from("foo");
53    let _ = String::from("foo");
54    #[allow(clippy::useless_conversion)]
55    {
56        let _: String = "foo".into();
57        let _ = String::from("foo");
58        let _ = "".lines().into_iter();
59    }
60
61    let _: String = "foo".to_string();
62    let _: String = "foo".to_string();
63    let _ = "foo".to_string();
64    let _ = format!("A: {:04}", 123);
65    let _ = "".lines();
66    let _ = vec![1, 2, 3].into_iter();
67    let _: String = format!("Hello {}", "world");
68
69    // keep parentheses around `a + b` for suggestion (see #4750)
70    let a: i32 = 1;
71    let b: i32 = 1;
72    let _ = (a + b) * 3;
73
74    // see #7205
75    let s: Foo<'a'> = Foo;
76    let _: Foo<'b'> = s.into();
77    let s2: Foo<'a'> = Foo;
78    let _: Foo<'a'> = s2;
79    let s3: Foo<'a'> = Foo;
80    let _ = s3;
81    let s4: Foo<'a'> = Foo;
82    let _ = vec![s4, s4, s4].into_iter();
83}
84
85#[derive(Copy, Clone)]
86struct Foo<const C: char>;
87
88impl From<Foo<'a'>> for Foo<'b'> {
89    fn from(_s: Foo<'a'>) -> Self {
90        Foo
91    }
92}
93