From bfda31b8416698e827775450bcd59079334347da Mon Sep 17 00:00:00 2001
From: TomHermsen <tomhermsen1999@gmail.com>
Date: Fri, 5 Jul 2024 14:31:33 +0200
Subject: [PATCH] Feat: More rules

- Implemented nullable rules
---
 package.json            |  2 +-
 src/Validator.ts        |  6 ++++++
 src/types/Rule.ts       |  1 +
 tests/validator.test.ts | 36 ++++++++++++++++++++++++++++++++++++
 4 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 79e4b19..c3e7108 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "checkmate-ts",
-    "version": "1.0.3",
+    "version": "1.0.4",
     "description": "Checkmate TypeScript - A powerful and flexible object validator written in TypeScript, supporting validation for various data types, nested objects, and arrays. Ensures type safety and reliability in data validation scenarios.",
     "type": "module",
     "exports": {
diff --git a/src/Validator.ts b/src/Validator.ts
index 7d8bfe4..379089b 100644
--- a/src/Validator.ts
+++ b/src/Validator.ts
@@ -36,7 +36,13 @@ class Validator<R extends Rules> {
   }
 
   private validateField(key: string, value: any, rules: Rule[], errors: { [key: string]: string[] }) {
+    const isNullable = rules.includes('nullable')
+
     rules.forEach(rule => {
+      if (isNullable && value == null) {
+        return // If the rule allows `null` values & the value is `null`, skip validating
+      }
+
       if (rule === 'required') {
         validateRequired(key, value, errors)
       } else if (rule === 'string') {
diff --git a/src/types/Rule.ts b/src/types/Rule.ts
index 5f132f3..49eeba6 100644
--- a/src/types/Rule.ts
+++ b/src/types/Rule.ts
@@ -1,4 +1,5 @@
 export type Rule =
+  | 'nullable'
   | 'required'
   | 'string'
   | `min:${number}`
diff --git a/tests/validator.test.ts b/tests/validator.test.ts
index 9011b81..664897b 100644
--- a/tests/validator.test.ts
+++ b/tests/validator.test.ts
@@ -202,4 +202,40 @@ describe('Validator', () => {
     const data = {tags: ['foo', 'test']}
     expect(() => validator.validateObject(data)).toThrow(ValidationError)
   })
+
+  test('should allow null on nullable string value', () => {
+    const validator = Validator.create({
+      'title': ['string', 'nullable'],
+    })
+
+    const data = {title: null}
+    expect(() => validator.validateObject(data)).not.toThrow(ValidationError)
+  })
+
+  test('should allow null on nullable array value', () => {
+    const validator = Validator.create({
+      'tags': ['array', 'nullable'],
+    })
+
+    const data = {tags: null}
+    expect(() => validator.validateObject(data)).not.toThrow(ValidationError)
+  })
+
+  test('should allow null on nullable number value', () => {
+    const validator = Validator.create({
+      'value': ['number', 'nullable'],
+    })
+
+    const data = {value: null}
+    expect(() => validator.validateObject(data)).not.toThrow(ValidationError)
+  })
+
+  test('should allow null on nullable numeric value', () => {
+    const validator = Validator.create({
+      'value': ['numeric', 'nullable'],
+    })
+
+    const data = {value: null}
+    expect(() => validator.validateObject(data)).not.toThrow(ValidationError)
+  })
 })