fix: validate required with Date as value

When the value of an input is a Date object, the required validator
returns an error.

Added check if value is a Date when validating object in required check.

Closes #41

src/validators.ts

@@ -9,6 +9,7 @@ import {
   NumberError,
   NumberFractionError
 } from './errors';
+import { isDate } from 'lodash';
 
 /* eslint-disable @typescript-eslint/no-explicit-any */
 
@@ -21,7 +22,9 @@ export function makeRequired(label: string): FieldValidator<any> {
       value === '' ||
       (typeof value === 'string' && value.trim() === '') ||
       (Array.isArray(value) && value.length === 0) ||
-      (typeof value === 'object' && Object.keys(value).length === 0) ||
+      (typeof value === 'object' &&
+        !isDate(value) &&
+        Object.keys(value).length === 0) ||
       // Prevent users from validating boolean values by always
       // considering it an error, they should use `makeBooleanRequired`
       // instead.

tests/validators.test.ts

@@ -33,7 +33,7 @@ function makeValidatorChecker(
 }
 
 test('required', async () => {
-  expect.assertions(15);
+  expect.assertions(16);
 
   const validator = makeRequired('Name');
 
@@ -138,6 +138,7 @@ test('required', async () => {
   await checkValidator({ value: 'henkie', expected: undefined });
   await checkValidator({ value: { test: true }, expected: undefined });
   await checkValidator({ value: ['test'], expected: undefined });
+  await checkValidator({ value: new Date(), expected: undefined });
 });
 
 test('booleanRequired', async () => {