6 clippy::redundant_closure_call,
7 clippy::many_single_char_names,
8 clippy::needless_pass_by_value,
9 clippy::option_map_unit_fn,
10 clippy::trivially_copy_pass_by_ref
12 #![warn(clippy::redundant_closure, clippy::needless_borrow)]
14 use std::path::PathBuf;
17 let a = Some(1u8).map(foo);
19 let c = Some(1u8).map({1+2; foo});
20 let d = Some(1u8).map(|a| foo((|b| foo2(b))(a))); //is adjusted?
21 all(&[1, 2, 3], &2, |x, y| below(x, y)); //is adjusted
23 Some(1u8).map(|a| unsafe_fn(a)); // unsafe fn
27 let e = Some(1u8).map(|a| divergent(a));
28 let e = Some(1u8).map(generic);
29 let e = Some(1u8).map(generic);
31 let a: Option<Box<::std::ops::Deref<Target = [i32]>>> =
32 Some(vec![1i32, 2]).map(|v| -> Box<::std::ops::Deref<Target = [i32]>> { Box::new(v) });
36 fn trait_foo(self) -> bool;
37 fn trait_foo_ref(&self) -> bool;
40 struct TestStruct<'a> {
44 impl<'a> TestStruct<'a> {
45 fn foo(self) -> bool {
48 unsafe fn foo_unsafe(self) -> bool {
53 impl<'a> TestTrait for TestStruct<'a> {
54 fn trait_foo(self) -> bool {
57 fn trait_foo_ref(&self) -> bool {
62 impl<'a> std::ops::Deref for TestStruct<'a> {
64 fn deref(&self) -> &char {
69 fn test_redundant_closures_containing_method_calls() {
71 let e = Some(TestStruct { some_ref: &i }).map(TestStruct::foo);
72 let e = Some(TestStruct { some_ref: &i }).map(TestStruct::foo);
73 let e = Some(TestStruct { some_ref: &i }).map(TestTrait::trait_foo);
74 let e = Some(TestStruct { some_ref: &i }).map(|a| a.trait_foo_ref());
75 let e = Some(TestStruct { some_ref: &i }).map(TestTrait::trait_foo);
76 let e = Some(&mut vec![1, 2, 3]).map(std::vec::Vec::clear);
77 let e = Some(&mut vec![1, 2, 3]).map(std::vec::Vec::clear);
79 let e = Some(TestStruct { some_ref: &i }).map(|a| a.foo_unsafe());
81 let e = Some("str").map(std::string::ToString::to_string);
82 let e = Some("str").map(str::to_string);
83 let e = Some('a').map(char::to_uppercase);
84 let e = Some('a').map(char::to_uppercase);
85 let e: std::vec::Vec<usize> = vec!['a', 'b', 'c'].iter().map(|c| c.len_utf8()).collect();
86 let e: std::vec::Vec<char> = vec!['a', 'b', 'c'].iter().map(char::to_ascii_uppercase).collect();
87 let e: std::vec::Vec<char> = vec!['a', 'b', 'c'].iter().map(char::to_ascii_uppercase).collect();
88 let p = Some(PathBuf::new());
89 let e = p.as_ref().and_then(|s| s.to_str());
90 let c = Some(TestStruct { some_ref: &i })
92 .map(|c| c.to_ascii_uppercase());
94 fn test_different_borrow_levels<T>(t: &[&T])
98 t.iter().filter(|x| x.trait_foo_ref());
99 t.iter().map(|x| x.trait_foo_ref());
102 let mut some = Some(|x| x * x);
103 let arr = [Ok(1), Err(2)];
104 let _: Vec<_> = arr.iter().map(|x| x.map_err(some.take().unwrap())).collect();
107 struct Thunk<T>(Box<FnMut() -> T>);
110 fn new<F: 'static + FnOnce() -> T>(f: F) -> Thunk<T> {
111 let mut option = Some(f);
112 // This should not trigger redundant_closure (#1439)
113 Thunk(Box::new(move || option.take().unwrap()()))
116 fn unwrap(self) -> T {
117 let Thunk(mut f) = self;
123 let thunk = Thunk::new(|| println!("Hello, world!"));
136 fn foo2(_: u8) -> u8 {
140 fn all<X, F>(x: &[X], y: &X, f: F) -> bool
142 F: Fn(&X, &X) -> bool,
144 x.iter().all(|e| f(e, y))
147 fn below(x: &u8, y: &u8) -> bool {
151 unsafe fn unsafe_fn(_: u8) {}
153 fn divergent(_: u8) -> ! {
157 fn generic<T>(_: T) -> u8 {
161 fn passes_fn_mut(mut x: Box<dyn FnMut()>) {
162 requires_fn_once(|| x());
164 fn requires_fn_once<T: FnOnce()>(_: T) {}
166 fn test_redundant_closure_with_function_pointer() {
167 type FnPtrType = fn(u8);
168 let foo_ptr: FnPtrType = foo;
169 let a = Some(1u8).map(foo_ptr);
172 fn test_redundant_closure_with_another_closure() {
173 let closure = |a| println!("{}", a);
174 let a = Some(1u8).map(closure);