1 files changed, 103 insertions, 0 deletions
diff --git a/library/std/benches/hash/map.rs b/library/std/benches/hash/map.rs
new file mode 100644
index 00000000000..bf646cbae47
--- /dev/null
+++ b/library/std/benches/hash/map.rs
@@ -0,0 +1,103 @@
+#![cfg(test)]
+
+use std::collections::HashMap;
+use test::Bencher;
+
+#[bench]
+fn new_drop(b: &mut Bencher) {
+    b.iter(|| {
+        let m: HashMap<i32, i32> = HashMap::new();
+        assert_eq!(m.len(), 0);
+    })
+}
+
+#[bench]
+fn new_insert_drop(b: &mut Bencher) {
+    b.iter(|| {
+        let mut m = HashMap::new();
+        m.insert(0, 0);
+        assert_eq!(m.len(), 1);
+    })
+}
+
+#[bench]
+fn grow_by_insertion(b: &mut Bencher) {
+    let mut m = HashMap::new();
+
+    for i in 1..1001 {
+        m.insert(i, i);
+    }
+
+    let mut k = 1001;
+
+    b.iter(|| {
+        m.insert(k, k);
+        k += 1;
+    });
+}
+
+#[bench]
+fn find_existing(b: &mut Bencher) {
+    let mut m = HashMap::new();
+
+    for i in 1..1001 {
+        m.insert(i, i);
+    }
+
+    b.iter(|| {
+        for i in 1..1001 {
+            m.contains_key(&i);
+        }
+    });
+}
+
+#[bench]
+fn find_nonexisting(b: &mut Bencher) {
+    let mut m = HashMap::new();
+
+    for i in 1..1001 {
+        m.insert(i, i);
+    }
+
+    b.iter(|| {
+        for i in 1001..2001 {
+            m.contains_key(&i);
+        }
+    });
+}
+
+#[bench]
+fn hashmap_as_queue(b: &mut Bencher) {
+    let mut m = HashMap::new();
+
+    for i in 1..1001 {
+        m.insert(i, i);
+    }
+
+    let mut k = 1;
+
+    b.iter(|| {
+        m.remove(&k);
+        m.insert(k + 1000, k + 1000);
+        k += 1;
+    });
+}
+
+#[bench]
+fn get_remove_insert(b: &mut Bencher) {
+    let mut m = HashMap::new();
+
+    for i in 1..1001 {
+        m.insert(i, i);
+    }
+
+    let mut k = 1;
+
+    b.iter(|| {
+        m.get(&(k + 400));
+        m.get(&(k + 2000));
+        m.remove(&k);
+        m.insert(k + 1000, k + 1000);
+        k += 1;
+    })
+}