Dev

CHANGELOG.md

@@ -1,6 +1,16 @@
 ## Changelog
 
-### [v6.0.3](https://github.com/panates/valgen/compare/v6.0.2...v6.0.3) - 
+### [v6.1.0](https://github.com/panates/valgen/compare/v6.0.3...v6.1.0) - 
+
+#### 🚀 New Features
+
+- feat: Added isInstanceOf validator with tests and export @Eray Hanoğlu 
+
+#### 🛠 Refactoring and Updates
+
+- refactor: Updated imports for consistency and maintenance, upgraded dependencies in package-lock.json @Eray Hanoğlu 
+
+### [v6.0.3](https://github.com/panates/valgen/compare/v6.0.2...v6.0.3) -  6 April 2026 
 
 #### 🛠 Refactoring and Updates
 

package.json

@@ -1,38 +1,39 @@
 {
   "name": "valgen",
   "description": "Fast runtime type validator, converter and io (encoding/decoding) library",
-  "version": "6.0.3",
+  "version": "6.1.0",
   "author": "Panates",
   "license": "MIT",
   "private": true,
   "dependencies": {
     "@browsery/validator": "^13.15.35",
+    "@jsopen/objects": "^2.2.1",
     "date-fns": "^4.1.0",
     "reflect-metadata": "^0.2.2",
-    "ts-gems": "^3.11.6",
+    "ts-gems": "^3.12.0",
     "tslib": "^2.8.1"
   },
   "devDependencies": {
-    "@panates/eslint-config": "^2.1.3",
-    "@panates/eslint-config-ts": "^2.1.3",
-    "@panates/tsconfig": "^2.1.3",
+    "@panates/eslint-config": "^2.1.6",
+    "@panates/eslint-config-ts": "^2.1.6",
+    "@panates/tsconfig": "^2.1.6",
     "@swc-node/register": "^1.11.1",
-    "@swc/core": "^1.15.24",
+    "@swc/core": "^1.15.32",
     "@swc/helpers": "^0.5.21",
     "@types/mocha": "^10.0.10",
-    "@types/node": "^25.5.2",
+    "@types/node": "^25.6.0",
     "auto-changelog": "^2.5.0",
     "c8": "^11.0.0",
     "expect": "^30.3.0",
-    "globals": "^17.4.0",
+    "globals": "^17.5.0",
     "husky": "^9.1.7",
     "dpdm": "^4.0.1",
     "mocha": "^11.7.5",
-    "npm-check-updates": "^20.0.0",
-    "prettier": "^3.8.1",
+    "npm-check-updates": "^22.0.1",
+    "prettier": "^3.8.3",
     "rimraf": "^6.1.3",
     "ts-cleanup": "^1.3.0",
-    "typescript": "^6.0.2"
+    "typescript": "^6.0.3"
   },
   "scripts": {
     "compile": "tsc --noEmit",

src/index.ts

@@ -1,8 +1,14 @@
-import { Context, ExecutionOptions } from './core/index.js';
+import type { Type } from 'ts-gems';
+import {
+  Context,
+  type ExecutionOptions,
+  type Validator,
+} from './core/index.js';
 import * as vg from './rules/index.js';
 
 export * from './constants.js';
 export * from './core/index.js';
+const isInstanceOfCache = new WeakMap<Type, Validator>();
 
 const isAlpha = vg.isAlpha();
 const isAlphanumeric = vg.isAlphanumeric();
@@ -27,6 +33,18 @@ const isHex = vg.isHex();
 const isHexColor = vg.isHexColor();
 const isIBAN = vg.isIBAN();
 const isInteger = vg.isInteger();
+const isInstanceOf = <T extends object>(
+  clazz: Type<T>,
+  input: any,
+  options?: vg.isInstanceOf.Options,
+) => {
+  let fn = isInstanceOfCache.get(clazz);
+  if (!fn) {
+    fn = vg.isInstanceOf(clazz);
+    isInstanceOfCache.set(clazz, fn);
+  }
+  return fn(input, options);
+};
 const isIP = vg.isIP();
 const isIPRange = vg.isIPRange();
 const isISSN = vg.isISSN();
@@ -108,6 +126,7 @@ export {
   isHex,
   isHexColor,
   isIBAN,
+  isInstanceOf,
   isInteger,
   isIP,
   isIPRange,

src/rules/index.ts

@@ -44,6 +44,7 @@ export * from './type-rules/is-bigint.js';
 export * from './type-rules/is-boolean.js';
 export * from './type-rules/is-date.js';
 export * from './type-rules/is-enum.js';
+export * from './type-rules/is-instanceof.js';
 export * from './type-rules/is-integer.js';
 export * from './type-rules/is-null.js';
 export * from './type-rules/is-number.js';

src/rules/type-rules/is-array.ts

@@ -1,11 +1,11 @@
-import {
-  type Context,
+import type {
+  Context,
   ErrorIssue,
-  type Nullish,
-  type ValidationOptions,
-  type Validator,
-  validator,
+  Nullish,
+  ValidationOptions,
+  Validator,
 } from '../../core/index.js';
+import { validator } from '../../core/index.js';
 
 /**
  * Validates if the value is "array" and applies validation for each item.

src/rules/type-rules/is-instanceof.ts

@@ -0,0 +1,39 @@
+import { isPlainObject } from '@jsopen/objects';
+import type { Type } from 'ts-gems';
+import {
+  type Context,
+  type Nullish,
+  type ValidationOptions,
+  validator,
+} from '../../core/index.js';
+
+/**
+ * Validates if the value instance of given class or classes
+ * @validator isUndefined
+ */
+export function isInstanceOf<T extends object>(
+  clazz: Type<T>,
+  options?: isInstanceOf.Options,
+) {
+  return validator<T, unknown>(
+    'isInstanceOf',
+    (input: unknown, context: Context, _this): Nullish<any> => {
+      if ((options?.coerce ?? context.coerce) && isPlainObject(input)) {
+        Object.setPrototypeOf(input, clazz.prototype);
+      }
+      if (!(input instanceof clazz)) {
+        context.fail(
+          _this,
+          `Value must be an instance of "${clazz.name}"`,
+          input,
+        );
+      }
+      return input;
+    },
+    options,
+  );
+}
+
+export namespace isInstanceOf {
+  export interface Options extends ValidationOptions {}
+}

src/rules/type-rules/is-record.ts

@@ -1,11 +1,11 @@
-import {
-  type Context,
+import type {
+  Context,
   ErrorIssue,
-  type Nullish,
-  type ValidationOptions,
-  type Validator,
-  validator,
+  Nullish,
+  ValidationOptions,
+  Validator,
 } from '../../core/index.js';
+import { validator } from '../../core/index.js';
 
 /**
  * Validates the record object according to given "key" and "value" rules

src/rules/utility-rules/all-of.ts

@@ -1,9 +1,9 @@
-import {
-  type Context,
+import type {
+  Context,
   ValidationOptions,
-  type Validator,
-  validator,
+  Validator,
 } from '../../core/index.js';
+import { validator } from '../../core/index.js';
 
 /**
  * Test given value against to all codecs and returns original input

src/rules/utility-rules/one-of.ts

@@ -1,9 +1,9 @@
-import {
-  type Context,
+import type {
+  Context,
   ValidationOptions,
-  type Validator,
-  validator,
+  Validator,
 } from '../../core/index.js';
+import { validator } from '../../core/index.js';
 
 type DiscriminatorRecord = Record<string, Validator>;
 

test/type-rules/is-instanceof.spec.ts

@@ -0,0 +1,39 @@
+import { expect } from 'expect';
+import { isInstanceOf } from 'valgen';
+
+describe('isInstanceOf', () => {
+  class Class1 {}
+  class Class2 {}
+
+  it('should validate value is instance of given class', () => {
+    const c1 = new Class1();
+    expect(isInstanceOf(Class1, c1)).toStrictEqual(c1);
+    expect(isInstanceOf(Class1, c1)).toBeInstanceOf(Class1);
+
+    expect(() => isInstanceOf(Class1, undefined)).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+    expect(() => isInstanceOf(Class1, {})).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+    expect(() => isInstanceOf(Class1, null)).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+    expect(() => isInstanceOf(Class1, 5)).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+    expect(() => isInstanceOf(Class1, 'x')).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+  });
+
+  it('should coerce plain object to given class', () => {
+    expect(isInstanceOf(Class1, {}, { coerce: true })).toBeInstanceOf(Class1);
+  });
+
+  it('should not coerce the object if is not plain', () => {
+    expect(() => isInstanceOf(Class1, new Class2(), { coerce: true })).toThrow(
+      'Value must be an instance of "Class1"',
+    );
+  });
+});