assertReturn (#735)

packages/util/src/assert.ts

@@ -30,3 +30,13 @@ export default function assert (condition: unknown, message: string | MessageFn)
     );
   }
 }
+
+/**
+ * @name assertReturn
+ * @summart Returns when the value is truthy, otherwise throws assertion error
+ */
+export function assertReturn <T> (value: T | undefined | null, message: string | MessageFn): T {
+  assert(value, message);
+
+  return value;
+}

packages/util/src/index.ts

@@ -7,7 +7,7 @@ import './polyfill';
  * @summary Utility methods for this package are split into groups
  */
 
-export { default as assert } from './assert';
+export { default as assert, assertReturn } from './assert';
 export { default as detectPackage } from './detectPackage';
 export { default as extractTime } from './extractTime';
 export { default as logger } from './logger';