feat: use IllegalStateError instead of AssertionError

index.ts

@@ -199,10 +199,10 @@ export function isDefined<T>(value: T): value is NonNullable<T> {
 /* eslint-disable @typescript-eslint/no-explicit-any, new-cap */
 
 /**
- * Always throws an `AssertionError` with the given message.
+ * Always throws an `IllegalStateError` with the given message.
  * It can come in handy when assigning values with a ternary operator or the null operators.
- * @param message the message for the `AssertionError`
- * @see AssertionError
+ * @param message the message for the `IllegalStateError`
+ * @see IllegalStateError
  * @example
  * function myFun(foo: string | null) {
  *   const bar = foo ?? error(PreconditionError, 'Argument may not be null');
@@ -215,26 +215,26 @@ export function error(
 /**
  * Always throws an error of the given type with the given message.
  * It can come in handy when assigning values with a ternary operator or the null operators.
- * @param errorType an error class, defaults to `AssertionError`
+ * @param errorType an error class
  * @param message the error message
- * @see AssertionError
+ * @see IllegalStateError
  * @example
  * function myFun(foo: string | null) {
  *   const bar = foo ?? error(PreconditionError, 'Argument may not be null');
  *   const result = bar.length > 0 ? 'OK' : error('Something went wrong!');
  * }
  */
 export function error(
-  errorType?: new (...args: any[]) => Error,
+  errorType: new (...args: any[]) => Error,
   message?: string
 ): never;
 
 export function error(
-  errorType: string | (new (...args: any[]) => Error) = AssertionError,
+  errorType?: string | (new (...args: any[]) => Error),
   message?: string
 ): never {
-  throw typeof errorType === 'string'
-    ? new AssertionError(errorType)
+  throw errorType == null || typeof errorType === 'string'
+    ? new IllegalStateError(errorType)
     : new errorType(message);
 }