Added test case for default value

Author: timocov

README.md

@@ -8,10 +8,10 @@ A TypeScript custom transformer which reduces bundle size (with a help of other
 
 ```typescript
 function showMessage(opts: { message: string }): void {
-	alert(opts.message);
+    alert(opts.message);
 }
 export function alertMessage(message: string): void {
-	showMessage({ message });
+    showMessage({ message });
 }
 ```
 

tests/test-cases/default-value/input.ts

@@ -0,0 +1,6 @@
+function showMessage(opts: { message: string } = { message: 'hello' }): void {
+	alert(opts.message);
+}
+export function alertMessage(message: string): void {
+	showMessage({ message });
+}

tests/test-cases/default-value/output.js

@@ -0,0 +1,10 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+function showMessage(opts) {
+    if (opts === void 0) { opts = { _internal_message: 'hello' }; }
+    alert(opts._internal_message);
+}
+function alertMessage(message) {
+    showMessage({ _internal_message: message });
+}
+exports.alertMessage = alertMessage;