From 9a6fcdb1f88b2404374708979358529869983c76 Mon Sep 17 00:00:00 2001
From: Evgeniy Kulikov <im@kulikov.im>
Date: Fri, 12 Apr 2019 14:19:18 +0300
Subject: [PATCH] =?UTF-8?q?=F0=9F=90=8C=20hot=20fix=20types?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 hrw.go      | 45 ++++++++++++++++++---------------------------
 hrw_test.go | 11 +++++++++++
 2 files changed, 29 insertions(+), 27 deletions(-)

diff --git a/hrw.go b/hrw.go
index 7e6bce1..9efe654 100644
--- a/hrw.go
+++ b/hrw.go
@@ -82,89 +82,80 @@ func SortSliceByValue(slice interface{}, hash uint64) {
 		return
 	}
 
-	switch val.Index(0).Interface().(type) {
-	case int:
+	switch slice := slice.(type) {
+	case []int:
 		var key = make([]byte, 16)
-		slice := slice.([]int)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint64(key, uint64(slice[i]))
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case uint:
+	case []uint:
 		var key = make([]byte, 16)
-		slice := slice.([]uint)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint64(key, uint64(slice[i]))
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case int8:
-		slice := slice.([]int8)
+	case []int8:
 		for i := 0; i < length; i++ {
 			key := byte(slice[i])
 			rule = append(rule, weight(Hash([]byte{key}), hash))
 		}
-	case uint8:
-		slice := slice.([]uint8)
+	case []uint8:
 		for i := 0; i < length; i++ {
 			key := slice[i]
 			rule = append(rule, weight(Hash([]byte{key}), hash))
 		}
-	case int16:
+	case []int16:
 		var key = make([]byte, 8)
-		slice := slice.([]int16)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint16(key, uint16(slice[i]))
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case uint16:
+	case []uint16:
 		var key = make([]byte, 8)
-		slice := slice.([]uint16)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint16(key, slice[i])
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case int32:
+	case []int32:
 		var key = make([]byte, 16)
-		slice := slice.([]int32)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint32(key, uint32(slice[i]))
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case uint32:
+	case []uint32:
 		var key = make([]byte, 16)
-		slice := slice.([]uint32)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint32(key, slice[i])
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case int64:
+	case []int64:
 		var key = make([]byte, 32)
-		slice := slice.([]int64)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint64(key, uint64(slice[i]))
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case uint64:
+	case []uint64:
 		var key = make([]byte, 32)
-		slice := slice.([]uint64)
 		for i := 0; i < length; i++ {
 			binary.BigEndian.PutUint64(key, slice[i])
 			rule = append(rule, weight(Hash(key), hash))
 		}
-	case string:
-		slice := slice.([]string)
+	case []string:
 		for i := 0; i < length; i++ {
 			rule = append(rule, weight(hash,
 				Hash([]byte(slice[i]))))
 		}
-	case Hasher:
+
+	default:
+		if _, ok := val.Index(0).Interface().(Hasher); !ok {
+			return
+		}
+
 		for i := 0; i < length; i++ {
 			h := val.Index(i).Interface().(Hasher)
 			rule = append(rule, weight(hash, h.Hash()))
 		}
-
-	default:
-		return
 	}
 
 	rule = SortByWeight(rule, hash)
diff --git a/hrw_test.go b/hrw_test.go
index 2e2fbbe..5f5a1dd 100644
--- a/hrw_test.go
+++ b/hrw_test.go
@@ -16,10 +16,16 @@ type (
 		actual interface{}
 		expect interface{}
 	}
+
+	Uint32Slice []uint32
 )
 
 var testKey = []byte("0xff51afd7ed558ccd")
 
+func (p Uint32Slice) Len() int           { return len(p) }
+func (p Uint32Slice) Less(i, j int) bool { return p[i] < p[j] }
+func (p Uint32Slice) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+
 func Example() {
 	// given a set of servers
 	servers := []string{
@@ -188,6 +194,11 @@ func TestSortSliceByValueIntSlice(t *testing.T) {
 			expect: []uint32{1, 3, 5, 4, 2, 0},
 		},
 
+		{
+			actual: Uint32Slice{0, 1, 2, 3, 4, 5},
+			expect: Uint32Slice{0, 1, 2, 3, 4, 5},
+		},
+
 		{
 			actual: []int64{0, 1, 2, 3, 4, 5},
 			expect: []int64{1, 5, 3, 4, 2, 0},