From 3a8d6360e6523df86917fa8ec085113765583b65 Mon Sep 17 00:00:00 2001
From: Faizan Khalid <IamFaizanKhalid@gmail.com>
Date: Thu, 10 Jun 2021 12:09:48 +0500
Subject: [PATCH 1/3] Added in tag

---
 builtins.go  | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 validator.go |  1 +
 2 files changed, 65 insertions(+)

diff --git a/builtins.go b/builtins.go
index 6fdb92b..b02bdde 100644
--- a/builtins.go
+++ b/builtins.go
@@ -20,6 +20,7 @@ import (
 	"reflect"
 	"regexp"
 	"strconv"
+	"strings"
 	"unicode/utf8"
 )
 
@@ -287,3 +288,66 @@ func nonnil(v interface{}, param string) error {
 	}
 	return nil
 }
+
+// in validates that the given value exists in list of given values
+func in(v interface{}, param string) error {
+	value := reflect.ValueOf(v)
+	if value.Kind() == reflect.Ptr {
+		if value.IsNil() {
+			return nil
+		}
+		value = value.Elem()
+	}
+
+	// get array of possible values
+	l := len(param)
+	if l < 3 || param[0] != '[' || param[l-1] != ']' {
+		return ErrBadParameter
+	}
+	param = param[1 : l-1]
+
+	possible := strings.Split(param, ",")
+
+	switch value.Kind() {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		for _, str := range possible {
+			i, err := strconv.ParseInt(str, 10, 64)
+			if err != nil {
+				return ErrBadParameter
+			}
+			if value.Int() == i {
+				return nil
+			}
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		for _, str := range possible {
+			i, err := strconv.ParseUint(str, 10, 64)
+			if err != nil {
+				return ErrBadParameter
+			}
+			if value.Uint() == i {
+				return nil
+			}
+		}
+	case reflect.Float32, reflect.Float64:
+		for _, str := range possible {
+			f, err := strconv.ParseFloat(str, 64)
+			if err != nil {
+				return ErrBadParameter
+			}
+			if value.Float() == f {
+				return nil
+			}
+		}
+	case reflect.String:
+		for _, str := range possible {
+			if value.String() == str {
+				return nil
+			}
+		}
+	default:
+		return ErrUnsupported
+	}
+
+	return ErrInvalid
+}
diff --git a/validator.go b/validator.go
index 4d610be..93e587d 100644
--- a/validator.go
+++ b/validator.go
@@ -140,6 +140,7 @@ func NewValidator() *Validator {
 			"max":     max,
 			"regexp":  regex,
 			"nonnil":  nonnil,
+			"in":      in,
 		},
 		printJSON: false,
 	}

From e01a7635c5ef94cd135c4ca130fa76c9ba2372fa Mon Sep 17 00:00:00 2001
From: Faizan Khalid <IamFaizanKhalid@gmail.com>
Date: Thu, 10 Jun 2021 12:18:59 +0500
Subject: [PATCH 2/3] Updated README

---
 README.md | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/README.md b/README.md
index ef9ada9..9783a80 100644
--- a/README.md
+++ b/README.md
@@ -86,6 +86,13 @@ regexp
 
 nonnil
 	Validates that the given value is not nil. (Usage: nonnil)
+
+in
+	Validates that the given value is present in a list of
+	provided values. These values should be provided inside
+	square brackets separated by comma without any additional
+	spaces. It can be used with strings, integers and floating
+	point numbers. (Usage: in=[FOO,BAR,BAZ])
 ```
 
 Custom validators

From d70861b3d479e14f5d0bc764760f02a73631ca4d Mon Sep 17 00:00:00 2001
From: Faizan Khalid <IamFaizanKhalid@gmail.com>
Date: Thu, 10 Jun 2021 12:21:21 +0500
Subject: [PATCH 3/3] Renamed validator in to list

---
 README.md    | 4 ++--
 builtins.go  | 4 ++--
 validator.go | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 9783a80..7288c25 100644
--- a/README.md
+++ b/README.md
@@ -87,12 +87,12 @@ regexp
 nonnil
 	Validates that the given value is not nil. (Usage: nonnil)
 
-in
+list
 	Validates that the given value is present in a list of
 	provided values. These values should be provided inside
 	square brackets separated by comma without any additional
 	spaces. It can be used with strings, integers and floating
-	point numbers. (Usage: in=[FOO,BAR,BAZ])
+	point numbers. (Usage: list=[FOO,BAR,BAZ])
 ```
 
 Custom validators
diff --git a/builtins.go b/builtins.go
index b02bdde..c257ea7 100644
--- a/builtins.go
+++ b/builtins.go
@@ -289,8 +289,8 @@ func nonnil(v interface{}, param string) error {
 	return nil
 }
 
-// in validates that the given value exists in list of given values
-func in(v interface{}, param string) error {
+// list validates that the given value exists in the list of values
+func list(v interface{}, param string) error {
 	value := reflect.ValueOf(v)
 	if value.Kind() == reflect.Ptr {
 		if value.IsNil() {
diff --git a/validator.go b/validator.go
index 93e587d..bc95d37 100644
--- a/validator.go
+++ b/validator.go
@@ -140,7 +140,7 @@ func NewValidator() *Validator {
 			"max":     max,
 			"regexp":  regex,
 			"nonnil":  nonnil,
-			"in":      in,
+			"list":    list,
 		},
 		printJSON: false,
 	}