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Co-authored-by: Alejandra González <blyxyas@gmail.com>

tests/ui/unused_enumerate_index.fixed

@@ -1,10 +1,58 @@
-// run-rustfix
 #![allow(unused)]
 #![warn(clippy::unused_enumerate_index)]
 
+use std::iter::Enumerate;
+
 fn main() {
     let v = [1, 2, 3];
     for x in v.iter() {
-        print!("{x}");
+        println!("{x}");
+    }
+
+    struct Dummy1;
+    impl Dummy1 {
+        fn enumerate(self) -> Vec<usize> {
+            vec![]
+        }
+    }
+    let dummy = Dummy1;
+    for x in dummy.enumerate() {
+        println!("{x}");
+    }
+
+    struct Dummy2;
+    impl Dummy2 {
+        fn enumerate(self) -> Enumerate<std::vec::IntoIter<usize>> {
+            vec![1, 2].into_iter().enumerate()
+        }
+    }
+    let dummy = Dummy2;
+    for (_, x) in dummy.enumerate() {
+        println!("{x}");
+    }
+
+    let mut with_used_iterator = [1, 2, 3].into_iter().enumerate();
+    with_used_iterator.next();
+    for (_, x) in with_used_iterator {
+        println!("{x}");
+    }
+
+    struct Dummy3(std::vec::IntoIter<usize>);
+
+    impl Iterator for Dummy3 {
+        type Item = usize;
+
+        fn next(&mut self) -> Option<Self::Item> {
+            self.0.next()
+        }
+
+        fn size_hint(&self) -> (usize, Option<usize>) {
+            self.0.size_hint()
+        }
+    }
+
+    let dummy = Dummy3(vec![1, 2, 3].into_iter());
+    for x in dummy {
+        println!("{x}");
     }
 }

tests/ui/unused_enumerate_index.rs

@@ -1,10 +1,58 @@
-// run-rustfix
 #![allow(unused)]
 #![warn(clippy::unused_enumerate_index)]
 
+use std::iter::Enumerate;
+
 fn main() {
     let v = [1, 2, 3];
     for (_, x) in v.iter().enumerate() {
-        print!("{x}");
+        println!("{x}");
+    }
+
+    struct Dummy1;
+    impl Dummy1 {
+        fn enumerate(self) -> Vec<usize> {
+            vec![]
+        }
+    }
+    let dummy = Dummy1;
+    for x in dummy.enumerate() {
+        println!("{x}");
+    }
+
+    struct Dummy2;
+    impl Dummy2 {
+        fn enumerate(self) -> Enumerate<std::vec::IntoIter<usize>> {
+            vec![1, 2].into_iter().enumerate()
+        }
+    }
+    let dummy = Dummy2;
+    for (_, x) in dummy.enumerate() {
+        println!("{x}");
+    }
+
+    let mut with_used_iterator = [1, 2, 3].into_iter().enumerate();
+    with_used_iterator.next();
+    for (_, x) in with_used_iterator {
+        println!("{x}");
+    }
+
+    struct Dummy3(std::vec::IntoIter<usize>);
+
+    impl Iterator for Dummy3 {
+        type Item = usize;
+
+        fn next(&mut self) -> Option<Self::Item> {
+            self.0.next()
+        }
+
+        fn size_hint(&self) -> (usize, Option<usize>) {
+            self.0.size_hint()
+        }
+    }
+
+    let dummy = Dummy3(vec![1, 2, 3].into_iter());
+    for (_, x) in dummy.enumerate() {
+        println!("{x}");
     }
 }

tests/ui/unused_enumerate_index.stderr

@@ -1,5 +1,5 @@
 error: you seem to use `.enumerate()` and immediately discard the index
-  --> $DIR/unused_enumerate_index.rs:7:19
+  --> $DIR/unused_enumerate_index.rs:8:19
    |
 LL |     for (_, x) in v.iter().enumerate() {
    |                   ^^^^^^^^^^^^^^^^^^^^
@@ -11,5 +11,16 @@ help: remove the `.enumerate()` call
 LL |     for x in v.iter() {
    |         ~    ~~~~~~~~
 
-error: aborting due to previous error
+error: you seem to use `.enumerate()` and immediately discard the index
+  --> $DIR/unused_enumerate_index.rs:55:19
+   |
+LL |     for (_, x) in dummy.enumerate() {
+   |                   ^^^^^^^^^^^^^^^^^
+   |
+help: remove the `.enumerate()` call
+   |
+LL |     for x in dummy {
+   |         ~    ~~~~~
+
+error: aborting due to 2 previous errors