1 files changed, 50 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/mem_replace.rs b/src/tools/clippy/tests/ui/mem_replace.rs
index bd7ad78b2af..b4ed5eafea9 100644
--- a/src/tools/clippy/tests/ui/mem_replace.rs
+++ b/src/tools/clippy/tests/ui/mem_replace.rs
@@ -11,53 +11,76 @@ use std::mem;
 fn replace_option_with_none() {
     let mut an_option = Some(1);
     let _ = mem::replace(&mut an_option, None);
+    //~^ mem_replace_option_with_none
     let an_option = &mut Some(1);
     let _ = mem::replace(an_option, None);
+    //~^ mem_replace_option_with_none
 }
 
 fn replace_with_default() {
     let mut s = String::from("foo");
     let _ = std::mem::replace(&mut s, String::default());
+    //~^ mem_replace_with_default
+    let _ = std::mem::replace(&mut s, String::new());
+    //~^ mem_replace_with_default
 
     let s = &mut String::from("foo");
     let _ = std::mem::replace(s, String::default());
+    //~^ mem_replace_with_default
+    let _ = std::mem::replace(s, String::new());
+    //~^ mem_replace_with_default
     let _ = std::mem::replace(s, Default::default());
+    //~^ mem_replace_with_default
 
     let mut v = vec![123];
     let _ = std::mem::replace(&mut v, Vec::default());
+    //~^ mem_replace_with_default
     let _ = std::mem::replace(&mut v, Default::default());
+    //~^ mem_replace_with_default
     let _ = std::mem::replace(&mut v, Vec::new());
+    //~^ mem_replace_with_default
     let _ = std::mem::replace(&mut v, vec![]);
+    //~^ mem_replace_with_default
 
     let mut hash_map: HashMap<i32, i32> = HashMap::new();
     let _ = std::mem::replace(&mut hash_map, HashMap::new());
+    //~^ mem_replace_with_default
 
     let mut btree_map: BTreeMap<i32, i32> = BTreeMap::new();
     let _ = std::mem::replace(&mut btree_map, BTreeMap::new());
+    //~^ mem_replace_with_default
 
     let mut vd: VecDeque<i32> = VecDeque::new();
     let _ = std::mem::replace(&mut vd, VecDeque::new());
+    //~^ mem_replace_with_default
 
     let mut hash_set: HashSet<&str> = HashSet::new();
     let _ = std::mem::replace(&mut hash_set, HashSet::new());
+    //~^ mem_replace_with_default
 
     let mut btree_set: BTreeSet<&str> = BTreeSet::new();
     let _ = std::mem::replace(&mut btree_set, BTreeSet::new());
+    //~^ mem_replace_with_default
 
     let mut list: LinkedList<i32> = LinkedList::new();
     let _ = std::mem::replace(&mut list, LinkedList::new());
+    //~^ mem_replace_with_default
 
     let mut binary_heap: BinaryHeap<i32> = BinaryHeap::new();
     let _ = std::mem::replace(&mut binary_heap, BinaryHeap::new());
+    //~^ mem_replace_with_default
 
     let mut tuple = (vec![1, 2], BinaryHeap::<i32>::new());
     let _ = std::mem::replace(&mut tuple, (vec![], BinaryHeap::new()));
+    //~^ mem_replace_with_default
 
     let mut refstr = "hello";
     let _ = std::mem::replace(&mut refstr, "");
+    //~^ mem_replace_with_default
 
     let mut slice: &[i32] = &[1, 2, 3];
     let _ = std::mem::replace(&mut slice, &[]);
+    //~^ mem_replace_with_default
 }
 
 // lint is disabled for primitives because in this case `take`
@@ -94,6 +117,7 @@ fn msrv_1_39() {
 fn msrv_1_40() {
     let mut s = String::from("foo");
     let _ = std::mem::replace(&mut s, String::default());
+    //~^ mem_replace_with_default
 }
 
 fn issue9824() {
@@ -124,8 +148,34 @@ fn issue9824() {
 
     // replace option with none
     let _ = std::mem::replace(&mut f.0, None);
+    //~^ mem_replace_option_with_none
     let _ = std::mem::replace(&mut *f, None);
+    //~^ mem_replace_option_with_none
     let _ = std::mem::replace(&mut b.opt, None);
+    //~^ mem_replace_option_with_none
     // replace with default
     let _ = std::mem::replace(&mut b.val, String::default());
+    //~^ mem_replace_with_default
+}
+
+#[clippy::msrv = "1.31"]
+fn mem_replace_option_with_some() {
+    let mut an_option = Some(0);
+    let replaced = mem::replace(&mut an_option, Some(1));
+    //~^ ERROR: replacing an `Option` with `Some(..)`
+
+    let mut an_option = &mut Some(0);
+    let replaced = mem::replace(an_option, Some(1));
+    //~^ ERROR: replacing an `Option` with `Some(..)`
+
+    let (mut opt1, mut opt2) = (Some(0), Some(0));
+    let b = true;
+    let replaced = mem::replace(if b { &mut opt1 } else { &mut opt2 }, Some(1));
+    //~^ ERROR: replacing an `Option` with `Some(..)`
+}
+
+#[clippy::msrv = "1.30"]
+fn mem_replace_option_with_some_bad_msrv() {
+    let mut an_option = Some(0);
+    let replaced = mem::replace(&mut an_option, Some(1));
 }