From 216a928861bbcd42c624ac907f59deadc278bbc1 Mon Sep 17 00:00:00 2001
From: John <john@johng.cn>
Date: Sat, 27 Jul 2019 15:36:52 +0800
Subject: [PATCH] add IsEmpty for gvar; add CompareVersion for gstr

---
 g/container/gvar/gvar.go |  6 ++++++
 g/text/gstr/gstr.go      | 32 ++++++++++++++++++++++++++++++++
 geg/other/test.go        |  8 +++++++-
 3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/g/container/gvar/gvar.go b/g/container/gvar/gvar.go
index 7cb88bdaa..1b2dfac9d 100644
--- a/g/container/gvar/gvar.go
+++ b/g/container/gvar/gvar.go
@@ -9,6 +9,7 @@ package gvar
 
 import (
 	"encoding/json"
+	"github.com/gogf/gf/g/internal/empty"
 	"time"
 
 	"github.com/gogf/gf/g/container/gtype"
@@ -70,6 +71,11 @@ func (v *Var) IsNil() bool {
 	return v.Val() == nil
 }
 
+// IsEmpty checks whether <v> is empty.
+func (v *Var) IsEmpty() bool {
+	return empty.IsEmpty(v.Val())
+}
+
 // Bytes converts and returns <v> as []byte.
 func (v *Var) Bytes() []byte {
 	return gconv.Bytes(v.Val())
diff --git a/g/text/gstr/gstr.go b/g/text/gstr/gstr.go
index 7098bc2b8..57237e4bd 100644
--- a/g/text/gstr/gstr.go
+++ b/g/text/gstr/gstr.go
@@ -599,3 +599,35 @@ func SearchArray(a []string, s string) int {
 func InArray(a []string, s string) bool {
 	return SearchArray(a, s) != -1
 }
+
+// CompareVersion compares <a> and <b> as standard golang version.
+// Golang standard version is as: 1.0.0, v1.0.1, v2.10.8, 10.2.0 etc.
+func CompareVersion(a, b string) int {
+	if a[0] == 'v' {
+		a = a[1:]
+	}
+	if b[0] == 'v' {
+		b = b[1:]
+	}
+	array1 := strings.Split(a, ".")
+	array2 := strings.Split(b, ".")
+	for i := 0; i < len(array2) - len(array1); i++ {
+		array1 = append(array1, "")
+	}
+	for i := 0; i < len(array1) - len(array2); i++ {
+		array2 = append(array2, "")
+	}
+	v1 := 0
+	v2 := 0
+	for i := 0; i < len(array1); i++ {
+		v1 = gconv.Int(array1[i])
+		v2 = gconv.Int(array2[i])
+		if v1 > v2 {
+			return 1
+		}
+		if v1 < v2 {
+			return -1
+		}
+	}
+	return 0
+}
diff --git a/geg/other/test.go b/geg/other/test.go
index 790580777..9c8e95194 100644
--- a/geg/other/test.go
+++ b/geg/other/test.go
@@ -1,5 +1,11 @@
 package main
 
-func main() {
+import (
+	"fmt"
+	"github.com/gogf/gf/g"
+)
 
+func main() {
+	latestVersion := g.NewVar(nil, true)
+	fmt.Println(latestVersion.IsNil())
 }