Merge pull request #118 from rezakhademix/feat-a-much-faster-email-regex

feat: a much faster regex check for email and mac address

email.go

@@ -1,14 +1,23 @@
 package govalidator
 
+import (
+	"regexp"
+	"strings"
+)
+
 const (
 	// Email represents rule name which will be used to find the default error message.
 	Email = "email"
 	// EmailMsg is the default error message format for fields with Email validation rule.
 	EmailMsg = "%s is not valid"
-	// EmailRegex is the default pattern to validate email field by RFC 5322 rule.
-	EmailRegex = "(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*|\"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*\")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\\[(?:(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9]))\\.){3}(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)\\])"
+
+	minEmailValidLen = 3
+	maxEmailValidLen = 320
 )
 
+// EmailRegex is the default pattern to validate email field by RFC 5322 rule.
+var EmailRegex = regexp.MustCompile(`^([a-z0-9!#$%&'*+/=?^_` + "`" + `{|}~-]+(?:\.[a-z0-9!#$%&'*+/=?^_` + "`" + `{|}~-]+)*|"(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21\x23-\x5b\x5d-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])*\")@(?:(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?|\[(?:(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9]))\.){3}(?:(2(5[0-5]|[0-4][0-9])|1[0-9][0-9]|[1-9]?[0-9])|[a-z0-9-]*[a-z0-9]:(?:[\x01-\x08\x0b\x0c\x0e-\x1f\x21-\x5a\x53-\x7f]|\\[\x01-\x09\x0b\x0c\x0e-\x7f])+)])$`)
+
 // Email checks the value under validation must match the EmailRegex regular expression.
 //
 // Example:
@@ -19,7 +28,12 @@ const (
 //		 fmt.Printf("validation errors: %#v\n", v.Errors())
 //	}
 func (v Validator) Email(s, field, msg string) Validator {
-	v.RegexMatches(s, EmailRegex, field, v.msg(Email, msg, field))
+	if len(s) < minEmailValidLen || len(s) > maxEmailValidLen || !strings.Contains(s, "@") {
+		v.check(false, field, v.msg(Email, msg, field))
+		return v
+	}
+
+	v.check(EmailRegex.MatchString(s), field, v.msg(Email, msg, field))
 
 	return v
 }

mac.go

@@ -1,14 +1,17 @@
 package govalidator
 
+import "regexp"
+
 const (
 	// MAC represents rule name which will be used to find the default error message.
 	MAC = "MAC"
 	// MACMsg is the default error message format for fields with MAC validation rule.
 	MACMsg = "%s is not valid"
-	// MACRegex is the default pattern to validate MAC address field.
-	MACRegex = "^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$"
 )
 
+// MACRegex is the default pattern to validate MAC address field.
+var MACRegex = regexp.MustCompile(`^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})`)
+
 // MAC checks the value under validation must match the MACRegex regular expression.
 //
 // Example:
@@ -19,7 +22,7 @@ const (
 //		 fmt.Printf("validation errors: %#v\n", v.Errors())
 //	}
 func (v Validator) MAC(s, field, msg string) Validator {
-	v.RegexMatches(s, MACRegex, field, v.msg(MAC, msg, field))
+	v.check(MACRegex.MatchString(s), field, v.msg(Email, msg, field))
 
 	return v
 }

regex.go

@@ -19,9 +19,7 @@ const (
 //		 fmt.Printf("validation errors: %#v\n", v.Errors())
 //	}
 func (v Validator) RegexMatches(s string, pattern string, field, msg string) Validator {
-	r := regexp.MustCompile(pattern)
-
-	v.check(r.Match([]byte(s)), field, v.msg(Regex, msg))
+	v.check(regexp.MustCompile(pattern).MatchString(s), field, v.msg(Regex, msg))
 
 	return v
 }