write to file tested.

__mocks__/fs.js

@@ -1,7 +1,7 @@
 const fs = jest.genMockFromModule('fs');
 
-const __writeFile = path => {
-	return path;
+const __writeFile = (path, script, cb) => {
+	return cb(null, path);
 };
 
 fs.writeFile = __writeFile;

src/getScript/helper/writeToFile.spec.js

@@ -0,0 +1,17 @@
+const writeToFile = require('./writeToFile');
+
+jest.mock('fs');
+
+describe('writeToFile', () => {
+	it('should return the file path of the script that is written to the FS', () => {
+		const path = 'script/frozen.html';
+		const mockScript = 'MOCK SCRIPT';
+		writeToFile(path, mockScript)
+			.then(result => {
+				expect(result).toBe(path);
+			})
+			.catch(err => {
+				console.error(err);
+			});
+	});
+});