improve the test coverage

Author: Sergey Khomushin

src/models/EmailJSResponseStatus.spec.ts

@@ -0,0 +1,34 @@
+import { EmailJSResponseStatus } from './EmailJSResponseStatus';
+
+it('should handle the success response', () => {
+  const error = new EmailJSResponseStatus({
+    status: 200,
+    responseText: 'OK',
+  } as XMLHttpRequest);
+
+  expect(error).toEqual({
+    status: 200,
+    text: 'OK',
+  });
+});
+
+it('should handle the fail response', () => {
+  const error = new EmailJSResponseStatus({
+    status: 404,
+    responseText: 'No Found',
+  } as XMLHttpRequest);
+
+  expect(error).toEqual({
+    status: 404,
+    text: 'No Found',
+  });
+});
+
+it('should handle the null response', () => {
+  const error = new EmailJSResponseStatus(null);
+
+  expect(error).toEqual({
+    status: 0,
+    text: 'Network Error',
+  });
+});

src/models/EmailJSResponseStatus.ts

@@ -4,6 +4,6 @@ export class EmailJSResponseStatus {
 
   constructor(httpResponse: XMLHttpRequest | null) {
     this.status = httpResponse?.status || 0;
-    this.text = httpResponse?.responseText || 'network error';
+    this.text = httpResponse?.responseText || 'Network Error';
   }
 }