allow multiple error messages

Author: anigenero

README.md

@@ -73,7 +73,7 @@ const MyComponent = () => {
             {/* show error */}
             {errors.username && (
                 <div className="error">
-                    {errors.username}
+                    {errors.username.map((message) => <strong>message</strong>)}
                 </div>
             )}
 

src/context.tsx

@@ -1,13 +1,13 @@
 import {ValidationError} from "class-validator";
 import React, {createContext, FunctionComponent} from "react";
 
-export type OnErrorMessageHandler = (error: ValidationError) => string;
+export type OnErrorMessageHandler = (error: ValidationError) => string[];
 export type ValidatorContextOptions = {
     onErrorMessage: OnErrorMessageHandler;
 };
 
 const _getDefaultContextOptions = (): ValidatorContextOptions => ({
-    onErrorMessage: (error) => Object.keys(error.constraints).map((key) => error.constraints[key])[0]
+    onErrorMessage: (error) => Object.keys(error.constraints).map((key) => error.constraints[key])
 });
 
 export const ValidatorContext = createContext<ValidatorContextOptions>(null);

src/index.ts

@@ -8,7 +8,7 @@ type Newable<T> = {
     new(): T;
 } | Function;
 
-type ValidationErrorMap<T, K extends keyof T> = { [key in K]?: string };
+type ValidationErrorMap<T, K extends keyof T> = { [key in K]?: string[] };
 type ValidationPayload<T, K extends keyof T> = { [key in K]?: T[K] };
 type ValidationFunction<T, K extends keyof T> = (payload: ValidationPayload<T, K>, filter?: K[]) => Promise<boolean>;
 type UseValidationResult<T, K extends keyof T> = [ValidationFunction<T, K>, ValidationErrorMap<T, K>];