Add Unittests to WEBGLExtensions (#22939)

* Add alliasses in WEBGLEntensions + Unittests

* revert webgl extensions change without aliases

* use || instead of ?? becuase of older version.

test/unit/src/renderers/webgl/WebGLExtensions.tests.js

@@ -2,6 +2,25 @@
 
 import { WebGLExtensions } from '../../../../../src/renderers/webgl/WebGLExtensions';
 
+const WebglContextMock = function ( supportedExtensions ) {
+
+	this.supportedExtensions = supportedExtensions || [];
+	this.getExtension = function ( name ) {
+
+		if ( this.supportedExtensions.indexOf( name ) > - 1 ) {
+
+			return { 'name': name };
+
+		} else {
+
+			return null;
+
+		}
+
+	};
+
+};
+
 export default QUnit.module( 'Renderers', () => {
 
 	QUnit.module( 'WebGL', () => {
@@ -9,16 +28,68 @@ export default QUnit.module( 'Renderers', () => {
 		QUnit.module( 'WebGLExtensions', () => {
 
 			// INSTANCING
-			QUnit.todo( "Instancing", ( assert ) => {
+			QUnit.test( 'Instancing', ( assert ) => {
+
+				const gl = new WebglContextMock();
+				const extensions = new WebGLExtensions( gl );
+				assert.ok( extensions !== undefined );
+
+			} );
+
+			QUnit.test( 'has', ( assert ) => {
+
+				const gl = new WebglContextMock( [ 'Extension1', 'Extension2' ] );
+				const extensions = new WebGLExtensions( gl );
+				assert.ok( extensions.has( 'Extension1' ) );
+				assert.ok( extensions.has( 'Extension2' ) );
+				assert.ok( extensions.has( 'Extension1' ) );
+				assert.notOk( extensions.has( 'NonExistingExtension' ) );
+
+			} );
+
+			QUnit.test( 'has (with aliasses)', ( assert ) => {
+
+				const gl = new WebglContextMock( [ 'WEBKIT_WEBGL_depth_texture' ] );
+				const extensions = new WebGLExtensions( gl );
+				assert.ok( extensions.has( 'WEBGL_depth_texture' ) );
+				assert.ok( extensions.has( 'WEBKIT_WEBGL_depth_texture' ) );
+				assert.notOk( extensions.has( 'EXT_texture_filter_anisotropic' ) );
+				assert.notOk( extensions.has( 'NonExistingExtension' ) );
+
+			} );
+
+			QUnit.test( 'get', ( assert ) => {
+
+				const gl = new WebglContextMock( [ 'Extension1', 'Extension2' ] );
+				const extensions = new WebGLExtensions( gl );
+				assert.ok( extensions.get( 'Extension1' ) );
+				assert.ok( extensions.get( 'Extension2' ) );
+				assert.ok( extensions.get( 'Extension1' ) );
+				assert.notOk( extensions.get( 'NonExistingExtension' ) );
+
+			} );
+
+			QUnit.test( 'get (with aliasses)', ( assert ) => {
 
-				assert.ok( false, "everything's gonna be alright" );
+				const gl = new WebglContextMock( [ 'WEBKIT_WEBGL_depth_texture' ] );
+				const extensions = new WebGLExtensions( gl );
+				assert.ok( extensions.get( 'WEBGL_depth_texture' ) );
+				assert.ok( extensions.get( 'WEBKIT_WEBGL_depth_texture' ) );
+				assert.notOk( extensions.get( 'EXT_texture_filter_anisotropic' ) );
+				assert.notOk( extensions.get( 'NonExistingExtension' ) );
 
 			} );
 
-			// PUBLIC STUFF
-			QUnit.todo( "get", ( assert ) => {
+			QUnit.test( 'init', ( assert ) => {
 
-				assert.ok( false, "everything's gonna be alright" );
+				const gl = new WebglContextMock();
+				const extensions = new WebGLExtensions( gl );
+				extensions.init( { isWebGL2: false } );
+				assert.ok( extensions );
+				const gl2 = new WebglContextMock();
+				const extensions2 = new WebGLExtensions( gl2 );
+				extensions2.init( { isWebGL2: true } );
+				assert.ok( extensions2 );
 
 			} );