fix(lazy): implement instanceof properly

Fixes: cdk8s-team/cdk8s#2164

Signed-off-by: Nikolai Prokoschenko <nikolai.prokoschenko@kurzdigital.com>

Author: rassie

docs/java.md

@@ -3666,6 +3666,7 @@ public java.lang.Object produce()
 | **Name** | **Description** |
 | --- | --- |
 | <code><a href="#cdk8s.Lazy.any">any</a></code> | *No description.* |
+| <code><a href="#cdk8s.Lazy.isLazy">isLazy</a></code> | Checks if an object is a Lazy instance. |
 
 ---
 
@@ -3683,6 +3684,24 @@ Lazy.any(IAnyProducer producer)
 
 ---
 
+##### `isLazy` <a name="isLazy" id="cdk8s.Lazy.isLazy"></a>
+
+```java
+import org.cdk8s.Lazy;
+
+Lazy.isLazy(java.lang.Object obj)
+```
+
+Checks if an object is a Lazy instance.
+
+###### `obj`<sup>Required</sup> <a name="obj" id="cdk8s.Lazy.isLazy.parameter.obj"></a>
+
+- *Type:* java.lang.Object
+
+The object to check.
+
+---
+
 
 
 ### LazyResolver <a name="LazyResolver" id="cdk8s.LazyResolver"></a>

docs/python.md

@@ -3881,6 +3881,7 @@ def produce() -> typing.Any
 | **Name** | **Description** |
 | --- | --- |
 | <code><a href="#cdk8s.Lazy.any">any</a></code> | *No description.* |
+| <code><a href="#cdk8s.Lazy.isLazy">is_lazy</a></code> | Checks if an object is a Lazy instance. |
 
 ---
 
@@ -3900,6 +3901,26 @@ cdk8s.Lazy.any(
 
 ---
 
+##### `is_lazy` <a name="is_lazy" id="cdk8s.Lazy.isLazy"></a>
+
+```python
+import cdk8s
+
+cdk8s.Lazy.is_lazy(
+  obj: typing.Any
+)
+```
+
+Checks if an object is a Lazy instance.
+
+###### `obj`<sup>Required</sup> <a name="obj" id="cdk8s.Lazy.isLazy.parameter.obj"></a>
+
+- *Type:* typing.Any
+
+The object to check.
+
+---
+
 
 
 ### LazyResolver <a name="LazyResolver" id="cdk8s.LazyResolver"></a>

docs/typescript.md

@@ -3183,6 +3183,7 @@ public produce(): any
 | **Name** | **Description** |
 | --- | --- |
 | <code><a href="#cdk8s.Lazy.any">any</a></code> | *No description.* |
+| <code><a href="#cdk8s.Lazy.isLazy">isLazy</a></code> | Checks if an object is a Lazy instance. |
 
 ---
 
@@ -3200,6 +3201,24 @@ Lazy.any(producer: IAnyProducer)
 
 ---
 
+##### `isLazy` <a name="isLazy" id="cdk8s.Lazy.isLazy"></a>
+
+```typescript
+import { Lazy } from 'cdk8s'
+
+Lazy.isLazy(obj: any)
+```
+
+Checks if an object is a Lazy instance.
+
+###### `obj`<sup>Required</sup> <a name="obj" id="cdk8s.Lazy.isLazy.parameter.obj"></a>
+
+- *Type:* any
+
+The object to check.
+
+---
+
 
 
 ### LazyResolver <a name="LazyResolver" id="cdk8s.LazyResolver"></a>

src/lazy.ts

@@ -1,9 +1,31 @@
+const LAZY_SYMBOL = Symbol.for("cdk8s.Lazy");
+
 export class Lazy {
   public static any(producer: IAnyProducer): any {
     return new Lazy(producer) as unknown as any;
   }
 
-  private constructor(private readonly producer: IAnyProducer) {}
+  /**
+   * Checks if an object is a Lazy instance
+   * @param obj The object to check
+   */
+  static isLazy(obj: any): boolean {
+    return obj !== null && typeof obj === "object" && LAZY_SYMBOL in obj;
+  }
+
+  /**
+   * Implements `instanceof Lazy` using the more reliable `Lazy.isLazy` static method
+   *
+   * @param obj The object to check
+   * @internal
+   */
+  public static [Symbol.hasInstance](obj: any): boolean {
+    return Lazy.isLazy(obj);
+  }
+
+  private constructor(private readonly producer: IAnyProducer) {
+    Object.defineProperty(this, LAZY_SYMBOL, { value: true });
+  }
 
   public produce(): any {
     return this.producer.produce();
@@ -13,5 +35,3 @@ export class Lazy {
 export interface IAnyProducer {
   produce(): any;
 }
-
-