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// run-rustfix
#![allow(
unused,
clippy::no_effect,
clippy::redundant_closure_call,
clippy::many_single_char_names,
clippy::needless_pass_by_value,
clippy::option_map_unit_fn
)]
#![warn(
clippy::redundant_closure,
clippy::redundant_closure_for_method_calls,
clippy::needless_borrow
)]
use std::path::PathBuf;
fn main() {
let a = Some(1u8).map(foo);
meta(foo);
let c = Some(1u8).map(|a| {1+2; foo}(a));
let d = Some(1u8).map(|a| foo((|b| foo2(b))(a))); //is adjusted?
all(&[1, 2, 3], &2, |x, y| below(x, y)); //is adjusted
unsafe {
Some(1u8).map(|a| unsafe_fn(a)); // unsafe fn
}
// See #815
let e = Some(1u8).map(|a| divergent(a));
let e = Some(1u8).map(generic);
let e = Some(1u8).map(generic);
// See #515
let a: Option<Box<dyn (::std::ops::Deref<Target = [i32]>)>> =
Some(vec![1i32, 2]).map(|v| -> Box<dyn (::std::ops::Deref<Target = [i32]>)> { Box::new(v) });
}
trait TestTrait {
fn trait_foo(self) -> bool;
fn trait_foo_ref(&self) -> bool;
}
struct TestStruct<'a> {
some_ref: &'a i32,
}
impl<'a> TestStruct<'a> {
fn foo(self) -> bool {
false
}
unsafe fn foo_unsafe(self) -> bool {
true
}
}
impl<'a> TestTrait for TestStruct<'a> {
fn trait_foo(self) -> bool {
false
}
fn trait_foo_ref(&self) -> bool {
false
}
}
impl<'a> std::ops::Deref for TestStruct<'a> {
type Target = char;
fn deref(&self) -> &char {
&'a'
}
}
fn test_redundant_closures_containing_method_calls() {
let i = 10;
let e = Some(TestStruct { some_ref: &i }).map(TestStruct::foo);
let e = Some(TestStruct { some_ref: &i }).map(TestStruct::foo);
let e = Some(TestStruct { some_ref: &i }).map(TestTrait::trait_foo);
let e = Some(TestStruct { some_ref: &i }).map(|a| a.trait_foo_ref());
let e = Some(TestStruct { some_ref: &i }).map(TestTrait::trait_foo);
let e = Some(&mut vec![1, 2, 3]).map(std::vec::Vec::clear);
let e = Some(&mut vec![1, 2, 3]).map(std::vec::Vec::clear);
unsafe {
let e = Some(TestStruct { some_ref: &i }).map(|a| a.foo_unsafe());
}
let e = Some("str").map(std::string::ToString::to_string);
let e = Some("str").map(str::to_string);
let e = Some('a').map(char::to_uppercase);
let e = Some('a').map(char::to_uppercase);
let e: std::vec::Vec<usize> = vec!['a', 'b', 'c'].iter().map(|c| c.len_utf8()).collect();
let e: std::vec::Vec<char> = vec!['a', 'b', 'c'].iter().map(char::to_ascii_uppercase).collect();
let e: std::vec::Vec<char> = vec!['a', 'b', 'c'].iter().map(char::to_ascii_uppercase).collect();
let p = Some(PathBuf::new());
let e = p.as_ref().and_then(|s| s.to_str());
let c = Some(TestStruct { some_ref: &i })
.as_ref()
.map(|c| c.to_ascii_uppercase());
fn test_different_borrow_levels<T>(t: &[&T])
where
T: TestTrait,
{
t.iter().filter(|x| x.trait_foo_ref());
t.iter().map(|x| x.trait_foo_ref());
}
let mut some = Some(|x| x * x);
let arr = [Ok(1), Err(2)];
let _: Vec<_> = arr.iter().map(|x| x.map_err(|e| some.take().unwrap()(e))).collect();
}
struct Thunk<T>(Box<dyn FnMut() -> T>);
impl<T> Thunk<T> {
fn new<F: 'static + FnOnce() -> T>(f: F) -> Thunk<T> {
let mut option = Some(f);
// This should not trigger redundant_closure (#1439)
Thunk(Box::new(move || option.take().unwrap()()))
}
fn unwrap(self) -> T {
let Thunk(mut f) = self;
f()
}
}
fn foobar() {
let thunk = Thunk::new(|| println!("Hello, world!"));
thunk.unwrap()
}
fn meta<F>(f: F)
where
F: Fn(u8),
{
f(1u8)
}
fn foo(_: u8) {}
fn foo2(_: u8) -> u8 {
1u8
}
fn all<X, F>(x: &[X], y: &X, f: F) -> bool
where
F: Fn(&X, &X) -> bool,
{
x.iter().all(|e| f(e, y))
}
fn below(x: &u8, y: &u8) -> bool {
x < y
}
unsafe fn unsafe_fn(_: u8) {}
fn divergent(_: u8) -> ! {
unimplemented!()
}
fn generic<T>(_: T) -> u8 {
0
}
fn passes_fn_mut(mut x: Box<dyn FnMut()>) {
requires_fn_once(|| x());
}
fn requires_fn_once<T: FnOnce()>(_: T) {}
fn test_redundant_closure_with_function_pointer() {
type FnPtrType = fn(u8);
let foo_ptr: FnPtrType = foo;
let a = Some(1u8).map(foo_ptr);
}
fn test_redundant_closure_with_another_closure() {
let closure = |a| println!("{}", a);
let a = Some(1u8).map(closure);
}
fn make_lazy(f: impl Fn() -> fn(u8) -> u8) -> impl Fn(u8) -> u8 {
// Currently f is called when result of make_lazy is called.
// If the closure is removed, f will be called when make_lazy itself is
// called. This changes semantics, so the closure must stay.
Box::new(move |x| f()(x))
}
fn call<F: FnOnce(&mut String) -> String>(f: F) -> String {
f(&mut "Hello".to_owned())
}
fn test_difference_in_mutability() {
call(|s| s.clone());
}
struct Bar;
impl std::ops::Deref for Bar {
type Target = str;
fn deref(&self) -> &str {
"hi"
}
}
fn test_deref_with_trait_method() {
let _ = [Bar].iter().map(|s| s.to_string()).collect::<Vec<_>>();
}
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