| //@aux-build:proc_macros.rs | |
| #![warn(clippy::mem_replace_with_default)] | |
| extern crate proc_macros; | |
| use proc_macros::{external, inline_macros}; | |
| use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, LinkedList, VecDeque}; | |
| use std::mem; | |
| fn main() { | |
| let mut s = String::from("foo"); | |
| let _ = std::mem::take(&mut s); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(&mut s); | |
| //~^ mem_replace_with_default | |
| let s = &mut String::from("foo"); | |
| let _ = std::mem::take(s); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(s); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(s); | |
| //~^ mem_replace_with_default | |
| let mut v = vec![123]; | |
| let _ = std::mem::take(&mut v); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(&mut v); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(&mut v); | |
| //~^ mem_replace_with_default | |
| let _ = std::mem::take(&mut v); | |
| //~^ mem_replace_with_default | |
| let mut hash_map: HashMap<i32, i32> = HashMap::new(); | |
| let _ = std::mem::take(&mut hash_map); | |
| //~^ mem_replace_with_default | |
| let mut btree_map: BTreeMap<i32, i32> = BTreeMap::new(); | |
| let _ = std::mem::take(&mut btree_map); | |
| //~^ mem_replace_with_default | |
| let mut vd: VecDeque<i32> = VecDeque::new(); | |
| let _ = std::mem::take(&mut vd); | |
| //~^ mem_replace_with_default | |
| let mut hash_set: HashSet<&str> = HashSet::new(); | |
| let _ = std::mem::take(&mut hash_set); | |
| //~^ mem_replace_with_default | |
| let mut btree_set: BTreeSet<&str> = BTreeSet::new(); | |
| let _ = std::mem::take(&mut btree_set); | |
| //~^ mem_replace_with_default | |
| let mut list: LinkedList<i32> = LinkedList::new(); | |
| let _ = std::mem::take(&mut list); | |
| //~^ mem_replace_with_default | |
| let mut binary_heap: BinaryHeap<i32> = BinaryHeap::new(); | |
| let _ = std::mem::take(&mut binary_heap); | |
| //~^ mem_replace_with_default | |
| let mut tuple = (vec![1, 2], BinaryHeap::<i32>::new()); | |
| let _ = std::mem::take(&mut tuple); | |
| //~^ mem_replace_with_default | |
| let mut refstr = "hello"; | |
| let _ = std::mem::take(&mut refstr); | |
| //~^ mem_replace_with_default | |
| let mut slice: &[i32] = &[1, 2, 3]; | |
| let _ = std::mem::take(&mut slice); | |
| //~^ mem_replace_with_default | |
| } | |
| #[inline_macros] | |
| fn macros(s: &mut String) { | |
| let _ = inline!(std::mem::take($s)); | |
| //~^ mem_replace_with_default | |
| let _ = external!(std::mem::replace($s, Default::default())); | |
| } | |
| // lint is disabled for primitives because in this case `take` | |
| // has no clear benefit over `replace` and sometimes is harder to read | |
| fn dont_lint_primitive() { | |
| let mut pbool = true; | |
| let _ = std::mem::replace(&mut pbool, false); | |
| let mut pint = 5; | |
| let _ = std::mem::replace(&mut pint, 0); | |
| } | |
| // lint is disabled for expressions that are not used because changing to `take` is not the | |
| // recommended fix. Additionally, the `replace` is #[must_use], so that lint will provide | |
| // the correct suggestion | |
| fn dont_lint_not_used() { | |
| let mut s = String::from("foo"); | |
| std::mem::replace(&mut s, String::default()); | |
| } | |
| #[clippy::msrv = "1.39"] | |
| fn msrv_1_39() { | |
| let mut s = String::from("foo"); | |
| let _ = std::mem::replace(&mut s, String::default()); | |
| } | |
| #[clippy::msrv = "1.40"] | |
| fn msrv_1_40() { | |
| let mut s = String::from("foo"); | |
| let _ = std::mem::take(&mut s); | |
| //~^ mem_replace_with_default | |
| } | |
| fn issue9824() { | |
| struct Bar { | |
| val: String, | |
| } | |
| let mut b = Bar { | |
| val: String::from("bar"), | |
| }; | |
| let _ = std::mem::take(&mut b.val); | |
| //~^ mem_replace_with_default | |
| } | |
| fn issue15785() { | |
| let mut text = String::from("foo"); | |
| let replaced = std::mem::take(dbg!(&mut text)); | |
| //~^ mem_replace_with_default | |
| } |