From 990de9556b604677b1282bd9baa8f2c9422bea93 Mon Sep 17 00:00:00 2001
From: Derek Collison <derek.collison@gmail.com>
Date: Tue, 13 Nov 2012 19:03:33 -0800
Subject: [PATCH] Fixed bug that incorrectly used len comparison on first in
 chain

---
 hashmap/hashmap.go      | 10 ++++++----
 hashmap/hashmap_test.go | 15 +++++++++++++++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/hashmap/hashmap.go b/hashmap/hashmap.go
index b318d06e..8eee0e64 100644
--- a/hashmap/hashmap.go
+++ b/hashmap/hashmap.go
@@ -104,13 +104,15 @@ func (h *HashMap) Set(key []byte, data interface{}) {
 func (h *HashMap) Get(key []byte) interface{} {
 	hk := h.Hash(key)
 	e := h.bkts[hk&h.msk]
-
 	// FIXME: Reorder on GET if chained?
 	// We unroll and optimize the comparison of keys.
-	for e != nil && len(key) == len(e.key) {
+	for e != nil {
+		i, klen := 0, len(key)
+		if klen != len(e.key) {
+			goto next
+		}
 		// We unroll and optimize the key comparison here.
 		// Compare _DWSZ at a time
-		i, klen := 0, len(key)
 		for ; klen >= _DWSZ; klen -= _DWSZ {
 			k1 := *(*uint64)(unsafe.Pointer(&key[i]))
 			k2 := *(*uint64)(unsafe.Pointer(&e.key[i]))
@@ -182,7 +184,7 @@ func (h *HashMap) resize(nsz uint32) {
 	h.msk = nmsk
 }
 
-const maxBktSize = (1<<31)-1
+const maxBktSize = (1 << 31) - 1
 
 // grow the HashMap's buckets by 2
 func (h *HashMap) grow() {
diff --git a/hashmap/hashmap_test.go b/hashmap/hashmap_test.go
index a053f6d3..943f8d3c 100644
--- a/hashmap/hashmap_test.go
+++ b/hashmap/hashmap_test.go
@@ -147,6 +147,21 @@ func TestSetDoesReplaceOnExisting(t *testing.T) {
 	}
 }
 
+func TestCollision(t *testing.T) {
+	h := New()
+	k1 := []byte("999")
+	k2 := []byte("1000")
+	h.Set(k1, "foo")
+	h.Set(k2, "bar")
+	all := h.All()
+	if len(all) != 2 {
+		t.Fatalf("Expected 2 vs %d\n", len(all))
+	}
+	if h.Get(k1) == nil {
+		t.Fatalf("Failed to get '999'\n")
+	}
+}
+
 func TestHashMapStats(t *testing.T) {
 	h := New()
 	h.rsz = false