1 files changed, 74 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/iter_over_hash_type.rs b/src/tools/clippy/tests/ui/iter_over_hash_type.rs
new file mode 100644
index 000000000..7000c8bf9
--- /dev/null
+++ b/src/tools/clippy/tests/ui/iter_over_hash_type.rs
@@ -0,0 +1,74 @@
+//@aux-build:proc_macros.rs
+#![feature(rustc_private)]
+#![warn(clippy::iter_over_hash_type)]
+use std::collections::{HashMap, HashSet};
+
+extern crate rustc_data_structures;
+
+extern crate proc_macros;
+
+fn main() {
+    let mut hash_set = HashSet::<i32>::new();
+    let mut hash_map = HashMap::<i32, i32>::new();
+    let mut fx_hash_map = rustc_data_structures::fx::FxHashMap::<i32, i32>::default();
+    let mut fx_hash_set = rustc_data_structures::fx::FxHashMap::<i32, i32>::default();
+    let vec = Vec::<i32>::new();
+
+    // test hashset
+    for x in &hash_set {
+        let _ = x;
+    }
+    for x in hash_set.iter() {
+        let _ = x;
+    }
+    for x in hash_set.clone() {
+        let _ = x;
+    }
+    for x in hash_set.drain() {
+        let _ = x;
+    }
+
+    // test hashmap
+    for (x, y) in &hash_map {
+        let _ = (x, y);
+    }
+    for x in hash_map.keys() {
+        let _ = x;
+    }
+    for x in hash_map.values() {
+        let _ = x;
+    }
+    for x in hash_map.values_mut() {
+        *x += 1;
+    }
+    for x in hash_map.iter() {
+        let _ = x;
+    }
+    for x in hash_map.clone() {
+        let _ = x;
+    }
+    for x in hash_map.drain() {
+        let _ = x;
+    }
+
+    // test type-aliased hashers
+    for x in fx_hash_set {
+        let _ = x;
+    }
+    for x in fx_hash_map {
+        let _ = x;
+    }
+
+    // shouldnt fire
+    for x in &vec {
+        let _ = x;
+    }
+    for x in vec {
+        let _ = x;
+    }
+
+    // should not lint, this comes from an external crate
+    proc_macros::external! {
+      for _ in HashMap::<i32, i32>::new() {}
+    }
+}