fix(types): Add type safety to browser.runtime.executeScript files option (#2142)

Co-authored-by: nickbar01234 <nickbar01234gmail.com>
Co-authored-by: Aaron <aaronklinker1@gmail.com>

packages/wxt-demo/src/entrypoints/background.ts

@@ -43,3 +43,14 @@ export default defineBackground({
     storage.setItem('session:startTime', Date.now());
   },
 });
+
+function _otherTypeChecksNotEvaluated() {
+  browser.scripting.executeScript({
+    target: { tabId: 1 },
+    files: [
+      '/background.js',
+      // @ts-expect-error: Should error for non-existing paths
+      '/other.js',
+    ],
+  });
+}

packages/wxt/src/browser.ts

@@ -10,6 +10,7 @@
  * @module wxt/browser
  */
 import { browser as _browser, type Browser } from '@wxt-dev/browser';
+import type { ScriptPublicPath } from './utils/inject-script';
 
 /**
  * This interface is empty because it is generated per-project when running `wxt prepare`. See:
@@ -23,9 +24,39 @@ export interface WxtRuntime {}
  */
 export interface WxtI18n {}
 
-export type WxtBrowser = Omit<typeof _browser, 'runtime' | 'i18n'> & {
+type ScriptInjection<Args extends any[], Result> =
+  Browser.scripting.ScriptInjection<Args, Result> extends infer T
+    ? T extends { files: string[] }
+      ? Omit<T, 'files'> & { files: ScriptPublicPath[] }
+      : T
+    : never;
+type InjectionResult<Result> = Array<
+  Browser.scripting.InjectionResult<Awaited<Result>>
+>;
+
+export interface WxtScripting {
+  executeScript: {
+    /**
+     * @see {@link Browser.scripting.executeScript}
+     */
+    <Args extends any[], Result>(
+      injection: ScriptInjection<Args, Result>,
+    ): Promise<InjectionResult<Result>>;
+    <Args extends any[], Result>(
+      injection: ScriptInjection<Args, Result>,
+      callback: (results: InjectionResult<Result>) => void,
+    ): void;
+  };
+}
+
+export type WxtBrowser = Omit<
+  typeof _browser,
+  'runtime' | 'i18n' | 'scripting'
+> & {
   runtime: WxtRuntime & Omit<(typeof _browser)['runtime'], 'getURL'>;
   i18n: WxtI18n & Omit<(typeof _browser)['i18n'], 'getMessage'>;
+  scripting: WxtScripting &
+    Omit<(typeof _browser)['scripting'], 'executeScript'>;
 };
 
 export const browser: WxtBrowser = _browser;