1 files changed, 74 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/iter_not_returning_iterator.rs b/src/tools/clippy/tests/ui/iter_not_returning_iterator.rs
new file mode 100644
index 000000000..cce216fc6
--- /dev/null
+++ b/src/tools/clippy/tests/ui/iter_not_returning_iterator.rs
@@ -0,0 +1,74 @@
+#![warn(clippy::iter_not_returning_iterator)]
+
+struct Data {
+    begin: u32,
+}
+
+struct Counter {
+    count: u32,
+}
+
+impl Data {
+    fn iter(&self) -> Counter {
+        todo!()
+    }
+
+    fn iter_mut(&self) -> Counter {
+        todo!()
+    }
+}
+
+struct Data2 {
+    begin: u32,
+}
+
+struct Counter2 {
+    count: u32,
+}
+
+impl Data2 {
+    fn iter(&self) -> Counter2 {
+        todo!()
+    }
+
+    fn iter_mut(&self) -> Counter2 {
+        todo!()
+    }
+}
+
+impl Iterator for Counter {
+    type Item = u32;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        todo!()
+    }
+}
+
+// Issue #8225
+trait Iter {
+    type I;
+    fn iter(&self) -> Self::I;
+}
+
+impl Iter for () {
+    type I = core::slice::Iter<'static, ()>;
+    fn iter(&self) -> Self::I {
+        [].iter()
+    }
+}
+
+struct S;
+impl S {
+    fn iter(&self) -> <() as Iter>::I {
+        ().iter()
+    }
+}
+
+struct S2([u8]);
+impl S2 {
+    fn iter(&self) -> core::slice::Iter<u8> {
+        self.0.iter()
+    }
+}
+
+fn main() {}