From 6aa7a319c2ae288600fda2dffe57b24508e54d1e Mon Sep 17 00:00:00 2001
From: kevin <wanjunfeng@gmail.com>
Date: Mon, 10 Aug 2020 14:53:01 +0800
Subject: [PATCH] refactor compare versions

---
 core/syncx/once_test.go    |   5 +-
 core/utils/version.go      | 123 ++++++++++++++++---------------------
 core/utils/version_test.go |   3 +-
 3 files changed, 58 insertions(+), 73 deletions(-)

diff --git a/core/syncx/once_test.go b/core/syncx/once_test.go
index 15f8f869..9e7fd71d 100644
--- a/core/syncx/once_test.go
+++ b/core/syncx/once_test.go
@@ -24,9 +24,10 @@ func BenchmarkOnce(b *testing.B) {
 	add := Once(func() {
 		v++
 	})
+
 	b.ResetTimer()
-	for i:=0;i<b.N;i++{
+	for i := 0; i < b.N; i++ {
 		add()
 	}
 	assert.Equal(b, 1, v)
-}
\ No newline at end of file
+}
diff --git a/core/utils/version.go b/core/utils/version.go
index cf43157a..9f98adc7 100644
--- a/core/utils/version.go
+++ b/core/utils/version.go
@@ -3,92 +3,75 @@ package utils
 import (
 	"strconv"
 	"strings"
+
+	"github.com/tal-tech/go-zero/core/mathx"
+	"github.com/tal-tech/go-zero/core/stringx"
 )
 
-//return 0 if they are equal,and 1 if v1>2,and 2 if v1<v2
-func Compare(v1, v2 string) int {
-	replaceMap := map[string]string{"V": "", "v": "", "-": "."}
-	for k, v := range replaceMap {
-		if strings.Contains(v1, k) {
-			v1 = strings.Replace(v1, k, v, -1)
-		}
-		if strings.Contains(v2, k) {
-			v2 = strings.Replace(v2, k, v, -1)
-		}
+var replacer = stringx.NewReplacer(map[string]string{
+	"V": "",
+	"v": "",
+	"-": ".",
+})
+
+// operator compare returns true if the first field and the third field equation holds else false
+func CompareVersions(v1, op, v2 string) bool {
+	result := compare(v1, v2)
+	switch op {
+	case "=", "==":
+		return result == 0
+	case "<":
+		return result == -1
+	case ">":
+		return result == 1
+	case "<=":
+		return result == -1 || result == 0
+	case ">=":
+		return result == 0 || result == 1
 	}
-	verStr1 := strings.Split(v1, ".")
-	verStr2 := strings.Split(v2, ".")
 
-	ver1 := strSlice2IntSlice(verStr1)
-	ver2 := strSlice2IntSlice(verStr2)
+	return false
+}
 
-	var shorter int
-	if len(ver1) > len(ver2) {
-		shorter = len(ver2)
-	} else {
-		shorter = len(ver1)
-	}
+// return -1 if v1<v2, 0 if they are equal, and 1 if v1>v2
+func compare(v1, v2 string) int {
+	v1 = replacer.Replace(v1)
+	v2 = replacer.Replace(v2)
+	fields1 := strings.Split(v1, ".")
+	fields2 := strings.Split(v2, ".")
+	ver1 := strsToInts(fields1)
+	ver2 := strsToInts(fields2)
+	shorter := mathx.MinInt(len(ver1), len(ver2))
 
 	for i := 0; i < shorter; i++ {
 		if ver1[i] == ver2[i] {
-			if shorter-1 == i {
-				if len(ver1) == len(ver2) {
-					return 0
-				} else {
-					if len(ver1) > len(ver2) {
-						return 1
-					} else {
-						return 2
-					}
-				}
-			}
-		} else if ver1[i] > ver2[i] {
-			return 1
+			continue
+		} else if ver1[i] < ver2[i] {
+			return -1
 		} else {
-			return 2
+			return 1
 		}
 	}
-	return -1
+
+	if len(ver1) < len(ver2) {
+		return -1
+	} else if len(ver1) == len(ver2) {
+		return 0
+	} else {
+		return 1
+	}
 }
 
-func strSlice2IntSlice(strs []string) []int64 {
+func strsToInts(strs []string) []int64 {
 	if len(strs) == 0 {
-		return []int64{}
+		return nil
 	}
-	retInt := make([]int64, 0, len(strs))
+
+	ret := make([]int64, 0, len(strs))
 	for _, str := range strs {
-		i, err := strconv.ParseInt(str, 10, 64)
-		if err == nil {
-			retInt = append(retInt, i)
-		}
+		i, _ := strconv.ParseInt(str, 10, 64)
+		ret = append(ret, i)
 	}
-	return retInt
-}
 
-//operator compare returns true if the first field and the third field  equation holds else false
-func CompareVersions(v1, operator, v2 string) bool {
-	com := Compare(v1, v2)
-	switch operator {
-	case "==":
-		if com == 0 {
-			return true
-		}
-	case "<":
-		if com == 2 {
-			return true
-		}
-	case ">":
-		if com == 1 {
-			return true
-		}
-	case "<=":
-		if com == 0 || com == 2 {
-			return true
-		}
-	case ">=":
-		if com == 0 || com == 1 {
-			return true
-		}
-	}
-	return false
+	return ret
 }
diff --git a/core/utils/version_test.go b/core/utils/version_test.go
index 90e75213..815a69af 100644
--- a/core/utils/version_test.go
+++ b/core/utils/version_test.go
@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"fmt"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -31,7 +32,7 @@ func TestCustomCompareVersions(t *testing.T) {
 	for _, each := range cases {
 		t.Run(each.ver1, func(t *testing.T) {
 			actual := CompareVersions(each.ver1, each.operator, each.ver2)
-			assert.Equal(t, each.out, actual)
+			assert.Equal(t, each.out, actual, fmt.Sprintf("%s vs %s", each.ver1, each.ver2))
 		})
 	}
 }