From 39505f0d785e067a6595fdadd643de79a2fa9a18 Mon Sep 17 00:00:00 2001
From: waynemwashuma <94756970+waynemwashuma@users.noreply.github.com>
Date: Wed, 26 Aug 2026 07:34:02 +0300
Subject: [PATCH 1/3] Add optional resource getters

---
 packages/ecs/src/world.js | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/packages/ecs/src/world.js b/packages/ecs/src/world.js
index 58e23f23..99bf1fce 100644
--- a/packages/ecs/src/world.js
+++ b/packages/ecs/src/world.js
@@ -366,6 +366,15 @@ export class World {
     return this.getResourceByTypeId(typeid(resourceType))
   }
 
+  /**
+   * @template T
+   * @param {Constructor<T>} resourceType
+   * @returns {T | undefined}
+   */
+  getOptionalResource(resourceType) {
+    return this.getOptionalResourceByTypeId(typeid(resourceType))
+  }
+
   /**
    * @template T
    * @param {TypeId} id

From 7c4b6d3e5ae409390f41da928c298311835b9c77 Mon Sep 17 00:00:00 2001
From: waynemwashuma <94756970+waynemwashuma@users.noreply.github.com>
Date: Wed, 26 Aug 2026 07:35:02 +0300
Subject: [PATCH 2/3] Refactor resource getters

---
 packages/ecs/src/world.js | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/packages/ecs/src/world.js b/packages/ecs/src/world.js
index 99bf1fce..0a39d840 100644
--- a/packages/ecs/src/world.js
+++ b/packages/ecs/src/world.js
@@ -381,9 +381,23 @@ export class World {
    * @returns {T}
    */
   getResourceByTypeId(id) {
+    const resource = this.getOptionalResourceByTypeId(id)
+
+    assert(resource, `The resource or resource alias \`${id}\` is non existent.`)
+
+    // SAFETY: The typeid should match the type, caller's responsibility
+    return /** @type {T}*/(resource)
+  }
+
+  /**
+   * @template T
+   * @param {TypeId} id
+   * @returns {T | undefined}
+   */
+  getOptionalResourceByTypeId(id) {
     const resource = this.resources.get(id)
 
-    if (resource) {
+    if (resource !== undefined) {
 
       // SAFETY: The typeid should match the type, caller's responsibility
       return /** @type {T}*/(resource)
@@ -391,11 +405,11 @@ export class World {
 
     const aliasedid = this.resourceAliases.get(id)
 
-    assert(aliasedid, `The resource or resource alias \`${id}\` is non existent.`)
+    if (aliasedid === undefined) return undefined
 
     const aliasedResource = this.resources.get(aliasedid)
 
-    assert(aliasedResource, `The resource alias \`${id}\` points to a non-existent resource \`${aliasedid}\`.`)
+    if (aliasedResource === undefined) return undefined
 
     // SAFETY: The aliased typeid should match the type, caller's responsibility
     return /** @type {T}*/(aliasedResource)

From fcf1a86b94c1b9c0b9f967a8d8a703417e185940 Mon Sep 17 00:00:00 2001
From: waynemwashuma <94756970+waynemwashuma@users.noreply.github.com>
Date: Wed, 26 Aug 2026 07:35:19 +0300
Subject: [PATCH 3/3] Add tests for optional resource getters

---
 packages/ecs/tests/world.test.js | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/packages/ecs/tests/world.test.js b/packages/ecs/tests/world.test.js
index 8777b8d8..1da09efc 100644
--- a/packages/ecs/tests/world.test.js
+++ b/packages/ecs/tests/world.test.js
@@ -1,5 +1,5 @@
 import { test, describe } from "vitest";
-import { deepStrictEqual, throws } from "node:assert";
+import { deepStrictEqual, strictEqual, throws } from "node:assert";
 import { World } from "../src";
 import { typeid } from "@wimaengine/type";
 import { EntityHandle } from "../src/entities";
@@ -109,6 +109,30 @@ describe("Testing `World`", () => {
     deepStrictEqual(resource, new TestResource())
   })
 
+  test('Get optional correct resource on world.', () => {
+    const world = new World()
+    world.setResource(new TestResource())
+    const resource = world.getOptionalResource(TestResource)
+
+    deepStrictEqual(resource, new TestResource())
+  })
+
+  test('Optional resource lookup on world returns aliased resources.', () => {
+    const world = new World()
+    world.setResource(new TestResource())
+    world.setResourceAlias(typeid(TestResource), TestAlias)
+    const resource = world.getOptionalResource(TestAlias)
+
+    deepStrictEqual(resource, new TestResource())
+  })
+
+  test('Optional resource lookup on world returns undefined when missing.', () => {
+    const world = new World()
+
+    strictEqual(world.getOptionalResource(TestResource), undefined)
+    strictEqual(world.getOptionalResource(TestAlias), undefined)
+  })
+
   test('World has resource.', () => {
     const world = new World()
     world.setResource(new TestResource())