From 0da37a784338f75dd2680142b4db32b0534b65d2 Mon Sep 17 00:00:00 2001
From: GoEdgeLab <goedgecloud@gmail.com>
Date: Mon, 4 Apr 2022 16:42:56 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BC=98=E5=8C=96=E4=BB=A3=E7=A0=81?=
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---
 pkg/configutils/variable.go      | 15 +++++++++++----
 pkg/configutils/variable_test.go | 10 ++++++++++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/pkg/configutils/variable.go b/pkg/configutils/variable.go
index 0c1f7af..b6c0687 100644
--- a/pkg/configutils/variable.go
+++ b/pkg/configutils/variable.go
@@ -16,6 +16,10 @@ var regexpNamedVariable = regexp.MustCompile(`\${[\w.-]+}`)
 
 // ParseVariables 分析变量
 func ParseVariables(source string, replacer func(varName string) (value string)) string {
+	if len(source) == 0 {
+		return ""
+	}
+
 	variableLocker.RLock()
 	holders, found := variableMapping[source]
 	variableLocker.RUnlock()
@@ -42,16 +46,16 @@ func ParseVariables(source string, replacer func(varName string) (value string))
 	}
 
 	// 多个占位时，使用Builder
-	result := strings.Builder{}
+	var builder = strings.Builder{}
 	for _, h := range holders {
 		holder, ok := h.(VariableHolder)
 		if ok {
-			result.WriteString(replacer(string(holder)))
+			builder.WriteString(replacer(string(holder)))
 		} else {
-			result.Write(h.([]byte))
+			builder.Write(h.([]byte))
 		}
 	}
-	return result.String()
+	return builder.String()
 }
 
 // ParseVariablesFromHolders 从占位中分析变量
@@ -92,5 +96,8 @@ func ParseHolders(source string) (holders VariableHolders) {
 
 // HasVariables 判断是否有变量
 func HasVariables(source string) bool {
+	if len(source) == 0 {
+		return false
+	}
 	return regexpNamedVariable.MatchString(source)
 }
diff --git a/pkg/configutils/variable_test.go b/pkg/configutils/variable_test.go
index 8cb2e3f..aff81f7 100644
--- a/pkg/configutils/variable_test.go
+++ b/pkg/configutils/variable_test.go
@@ -53,6 +53,8 @@ func BenchmarkParseVariables(b *testing.B) {
 		return "Lu"
 	})
 
+	b.ResetTimer()
+
 	for i := 0; i < b.N; i++ {
 		_ = ParseVariables("hello, ${name}, ${age}, ${gender}, ${home}, world", func(s string) string {
 			return "Lu"
@@ -95,3 +97,11 @@ func BenchmarkParseNoVariables(b *testing.B) {
 		})
 	}
 }
+
+func BenchmarkParseEmpty(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		_ = ParseVariables("", func(s string) string {
+			return "Lu"
+		})
+	}
+}