--- /dev/null
+// run-rustfix
+
+#![warn(clippy::all, clippy::pedantic)]
+#![allow(clippy::let_underscore_drop)]
+#![allow(clippy::missing_docs_in_private_items)]
+#![allow(clippy::map_identity)]
+#![allow(clippy::unnecessary_wraps)]
+
+fn main() {
+ // mapping to Option on Iterator
+ fn option_id(x: i8) -> Option<i8> {
+ Some(x)
+ }
+ let option_id_ref: fn(i8) -> Option<i8> = option_id;
+ let option_id_closure = |x| Some(x);
+ let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id).flatten().collect();
+ let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id_ref).flatten().collect();
+ let _: Vec<_> = vec![5_i8; 6].into_iter().map(option_id_closure).flatten().collect();
+ let _: Vec<_> = vec![5_i8; 6].into_iter().map(|x| x.checked_add(1)).flatten().collect();
+
+ // mapping to Iterator on Iterator
+ let _: Vec<_> = vec![5_i8; 6].into_iter().map(|x| 0..x).flatten().collect();
+
+ // mapping to Option on Option
+ let _: Option<_> = (Some(Some(1))).map(|x| x).flatten();
+}