diff options
Diffstat (limited to 'src/test/ui/issues/issue-52126-assign-op-invariance.rs')
-rw-r--r-- | src/test/ui/issues/issue-52126-assign-op-invariance.rs | 49 |
1 files changed, 0 insertions, 49 deletions
diff --git a/src/test/ui/issues/issue-52126-assign-op-invariance.rs b/src/test/ui/issues/issue-52126-assign-op-invariance.rs deleted file mode 100644 index c96cfdf3c..000000000 --- a/src/test/ui/issues/issue-52126-assign-op-invariance.rs +++ /dev/null @@ -1,49 +0,0 @@ -// Issue 52126: With respect to variance, the assign-op's like += were -// accidentally lumped together with other binary op's. In both cases -// we were coercing the LHS of the op to the expected supertype. -// -// The problem is that since the LHS of += is modified, we need the -// parameter to be invariant with respect to the overall type, not -// covariant. - -use std::collections::HashMap; -use std::ops::AddAssign; - -pub fn main() { - panics(); -} - -pub struct Counter<'l> { - map: HashMap<&'l str, usize>, -} - -impl<'l> AddAssign for Counter<'l> -{ - fn add_assign(&mut self, rhs: Counter<'l>) { - rhs.map.into_iter().for_each(|(key, val)| { - let count = self.map.entry(key).or_insert(0); - *count += val; - }); - } -} - -/// Often crashes, if not prints invalid strings. -pub fn panics() { - let mut acc = Counter{map: HashMap::new()}; - for line in vec!["123456789".to_string(), "12345678".to_string()] { - let v: Vec<&str> = line.split_whitespace().collect(); - //~^ ERROR `line` does not live long enough - // println!("accumulator before add_assign {:?}", acc.map); - let mut map = HashMap::new(); - for str_ref in v { - let e = map.entry(str_ref); - println!("entry: {:?}", e); - let count = e.or_insert(0); - *count += 1; - } - let cnt2 = Counter{map}; - acc += cnt2; - // println!("accumulator after add_assign {:?}", acc.map); - // line gets dropped here but references are kept in acc.map - } -} |