feat: allow readonly array argument for IsIn IsNotIn validators (#600)

Author: bogdan

src/decorator/common/IsIn.ts

@@ -6,14 +6,14 @@ export const IS_IN = "isIn";
 /**
  * Checks if given value is in a array of allowed values.
  */
-export function isIn(value: unknown, possibleValues: unknown[]): boolean {
+export function isIn(value: unknown, possibleValues: readonly unknown[]): boolean {
     return !(possibleValues instanceof Array) || possibleValues.some(possibleValue => possibleValue === value);
 }
 
 /**
  * Checks if given value is in a array of allowed values.
  */
-export function IsIn(values: any[], validationOptions?: ValidationOptions): PropertyDecorator {
+export function IsIn(values: readonly any[], validationOptions?: ValidationOptions): PropertyDecorator {
     return ValidateBy(
         {
             name: IS_IN,

src/decorator/common/IsNotIn.ts

@@ -6,14 +6,14 @@ export const IS_NOT_IN = "isNotIn";
 /**
  * Checks if given value not in a array of allowed values.
  */
-export function isNotIn(value: unknown, possibleValues: unknown[]): boolean {
+export function isNotIn(value: unknown, possibleValues: readonly unknown[]): boolean {
     return !(possibleValues instanceof Array) || !possibleValues.some(possibleValue => possibleValue === value);
 }
 
 /**
  * Checks if given value not in a array of allowed values.
  */
-export function IsNotIn(values: any[], validationOptions?: ValidationOptions): PropertyDecorator {
+export function IsNotIn(values: readonly any[], validationOptions?: ValidationOptions): PropertyDecorator {
     return ValidateBy(
         {
             name: IS_NOT_IN,

test/functional/validation-functions-and-decorators.spec.ts

@@ -437,7 +437,7 @@ describe("IsNotEmpty", () => {
 });
 
 describe("IsIn", () => {
-    const constraint = ["foo", "bar"];
+    const constraint = ["foo", "bar"] as const;
     const validValues = ["foo", "bar"];
     const invalidValues = ["foobar", "barfoo", ""];
 
@@ -470,7 +470,7 @@ describe("IsIn", () => {
 });
 
 describe("IsNotIn", () => {
-    const constraint = ["foo", "bar"];
+    const constraint = ["foo", "bar"] as const;
     const validValues = ["foobar", "barfoo", ""];
     const invalidValues = ["foo", "bar"];