Narrow typing of loadCKEditorCloud result

src/cdn/loadCKEditorCloud.ts

@@ -12,7 +12,9 @@ import {
 	type CKBoxCdnBundlePackConfig
 } from './ckbox/createCKBoxCdnBundlePack';
 
+import type { ConditionalBlank } from '../types/ConditionalBlank';
 import type { CKCdnVersion } from './ck/createCKCdnUrl';
+
 import {
 	loadCKCdnResourcesPack,
 	type InferCKCdnResourcesPackExportsType
@@ -70,9 +72,9 @@ import {
  * Type of plugins can be inferred if `checkPluginLoaded` is not provided: In this case,
  * the type of the plugin will be picked from the global window scope.
  */
-export function loadCKEditorCloud<Plugins extends CdnPluginsPacks>(
-	config: CKEditorCloudConfig<Plugins>
-): Promise<CKEditorCloudResult<Plugins>> {
+export function loadCKEditorCloud<Config extends CKEditorCloudConfig>(
+	config: Config
+): Promise<CKEditorCloudResult<Config>> {
 	const {
 		version, languages, plugins,
 		premium, ckbox
@@ -98,34 +100,42 @@ export function loadCKEditorCloud<Plugins extends CdnPluginsPacks>(
 		loadedPlugins: combineCdnPluginsPacks( plugins ?? {} )
 	} );
 
-	return loadCKCdnResourcesPack( pack ) as Promise<CKEditorCloudResult<Plugins>>;
+	return loadCKCdnResourcesPack( pack ) as Promise<CKEditorCloudResult<Config>>;
 }
 
 /**
  * The result of the resolved bundles from CKEditor Cloud Services.
  */
-export type CKEditorCloudResult<Plugins extends CdnPluginsPacks = any> = {
+export type CKEditorCloudResult<Config extends CKEditorCloudConfig> = {
 
 	/**
 	 * The base CKEditor bundle exports.
 	 */
 	CKEditor: NonNullable<Window['CKEDITOR']>;
 
 	/**
-	 * The CKEditor Premium Features bundle exports.
+	 * The CKBox bundle exports.
+	 * It's available only if the `ckbox` configuration is provided.
 	 */
-	CKEditorPremiumFeatures?: Window['CKEDITOR_PREMIUM_FEATURES'];
+	CKBox: ConditionalBlank<
+		Config['ckbox'],
+		Window['CKBox']
+	>;
 
 	/**
-	 * The CKBox bundle exports.
+	 * The CKEditor Premium Features bundle exports.
+	 * It's available only if the `premium` configuration is provided.
 	 */
-	CKBox?: Window['CKBox'];
+	CKEditorPremiumFeatures: ConditionalBlank<
+		Config['premium'],
+		Window['CKEDITOR_PREMIUM_FEATURES']
+	>;
 
 	/**
 	 * The additional resources exports.
 	 */
 	loadedPlugins: InferCKCdnResourcesPackExportsType<
-		CombinedPluginsPackWithFallbackScope<Plugins>
+		CombinedPluginsPackWithFallbackScope<NonNullable<Config['plugins']>>
 	>;
 };
 

src/types/ConditionalBlank.ts

@@ -0,0 +1,13 @@
+/**
+ * @license Copyright (c) 2003-2024, CKSource Holding sp. z o.o. All rights reserved.
+ * For licensing, see LICENSE.md.
+ */
+
+/**
+ * A type that allows to set a value or leave it blank conditionally.
+ * It's useful when we provide config, and depending on the config, we want to set a value or leave it blank.
+ */
+export type ConditionalBlank<Condition, Value> =
+	Condition extends true | object ? NonNullable<Value> :
+	Condition extends boolean ? NonNullable<Value> | undefined :
+	undefined;

tests/cdn/loadCKEditorCloud.test.ts

@@ -8,6 +8,8 @@ import {
 	expectTypeOf, beforeEach, afterEach
 } from 'vitest';
 
+import type { AIAdapter } from 'ckeditor5-premium-features';
+
 import { loadCKEditorCloud } from '@/cdn/loadCKEditorCloud';
 import { createCKBoxBundlePack } from '@/cdn/ckbox/createCKBoxCdnBundlePack';
 import { removeCkCdnLinks, removeCkCdnScripts } from 'tests/_utils/ckCdnMocks';
@@ -76,7 +78,7 @@ describe( 'loadCKEditorCloud', () => {
 		expect( loadedPlugins?.Plugin ).toBeDefined();
 	} );
 
-	describe( 'plugins', () => {
+	describe( 'typings', () => {
 		it( 'should properly infer type of global variable if checkPluginLoaded is not provided', async () => {
 			const { loadedPlugins } = await loadCKEditorCloud( {
 				version: '43.0.0',
@@ -101,6 +103,49 @@ describe( 'loadCKEditorCloud', () => {
 
 			expectTypeOf( loadedPlugins.FakePlugin ).toEqualTypeOf<FakePlugin2>();
 		} );
+
+		it( 'should set CKBox result type as non-nullable if ckbox config is provided', async () => {
+			const { CKBox } = await loadCKEditorCloud( {
+				version: '43.0.0',
+				ckbox: {
+					version: '2.5.1'
+				}
+			} );
+
+			expectTypeOf( CKBox ).not.toBeNullable();
+		} );
+
+		it( 'should set CKBox result type as nullable if ckbox config is not provided', async () => {
+			const { CKBox } = await loadCKEditorCloud( {
+				version: '43.0.0'
+			} );
+
+			expectTypeOf( CKBox ).toBeUndefined();
+		} );
+
+		it( 'should set CKEditorPremiumFeatures type as non-nullable if premium=true config is provided', async () => {
+			const { CKEditorPremiumFeatures } = await loadCKEditorCloud( {
+				version: '43.0.0',
+				premium: true,
+				ckbox: {
+					version: '2.5.1'
+				}
+			} );
+
+			expectTypeOf( CKEditorPremiumFeatures ).not.toBeNullable();
+			expectTypeOf( CKEditorPremiumFeatures.AIAdapter ).toEqualTypeOf<typeof AIAdapter>();
+		} );
+
+		it( 'should set CKEditorPremiumFeatures type as nullable if premium=true config is not provided', async () => {
+			const { CKEditorPremiumFeatures } = await loadCKEditorCloud( {
+				version: '43.0.0',
+				ckbox: {
+					version: '2.5.1'
+				}
+			} );
+
+			expectTypeOf( CKEditorPremiumFeatures ).toBeUndefined();
+		} );
 	} );
 } );