add benchmark for dict

benchmarks/dict_0.py

@@ -0,0 +1,20 @@
+# test basic get/set
+import random
+random.seed(7)
+
+a = {str(i): i for i in range(100)}
+a['existed'] = 0
+a['missed'] = 0
+
+for i in range(1000000):
+    key = str(random.randint(-100, 100))
+    if key in a:
+        a['existed'] += 1
+    else:
+        a['missed'] += 1
+
+existed = a['existed']
+missed = a['missed']
+
+assert abs(existed - missed) < 10000
+

benchmarks/dict_1.py

@@ -0,0 +1,27 @@
+# test deletion
+rnd = 0
+keys = []
+while True:
+    keys.append(rnd)
+    rnd = ((rnd * 5) + 1) & 1023
+    if rnd == 0:
+        break
+
+assert len(keys) == 1024
+
+a = {k: k for k in keys}
+
+for i in range(10000):
+    if i % 2 == 0:
+        # del all keys
+        for k in keys:
+            del a[k]
+        assert len(a) == 0
+    else:
+        # add keys back
+        for k in keys:
+            a[k] = k
+        assert len(a) == len(keys)
+
+assert len(a) == len(keys)
+assert list(a.keys()) == keys   # order matters