+// 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
+)]
-#![allow(unknown_lints, unused, no_effect, redundant_closure_call, many_single_char_names, needless_pass_by_value, option_map_unit_fn)]
-#![warn(redundant_closure, needless_borrow)]
+use std::path::PathBuf;
fn main() {
let a = Some(1u8).map(|a| foo(a));
let e = Some(1u8).map(|a| generic(a));
let e = Some(1u8).map(generic);
// See #515
- let a: Option<Box<::std::ops::Deref<Target = [i32]>>> =
- Some(vec![1i32, 2]).map(|v| -> Box<::std::ops::Deref<Target = [i32]>> { Box::new(v) });
+ 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) });
}
-fn meta<F>(f: F) where F: Fn(u8) {
- f(1u8)
+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(|a| a.foo());
+ let e = Some(TestStruct { some_ref: &i }).map(TestStruct::foo);
+ let e = Some(TestStruct { some_ref: &i }).map(|a| a.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(|v| v.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(|s| s.to_string());
+ let e = Some("str").map(str::to_string);
+ let e = Some('a').map(|s| s.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(|c| c.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 foo(_: u8) {
+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 {
+where
+ F: Fn(&X, &X) -> bool,
+{
x.iter().all(|e| f(e, y))
}
-fn below(x: &u8, y: &u8) -> bool { x < y }
+fn below(x: &u8, y: &u8) -> bool {
+ x < y
+}
-unsafe fn unsafe_fn(_: u8) { }
+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(|a| foo_ptr(a));
+}
+
+fn test_redundant_closure_with_another_closure() {
+ let closure = |a| println!("{}", a);
+ let a = Some(1u8).map(|a| closure(a));
+}
+
+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<_>>();
+}
projects / rust.git / blobdiff