FirebaseStub: added auth User class

__mocks__/gatsby-plugin-firebase/auth/user.js

@@ -0,0 +1,60 @@
+/* eslint-disable no-underscore-dangle */
+import Constants from '../constants/auth';
+import { delay } from '../../../src/utils/index';
+
+class User {
+  /**
+   * Creates a new user.
+   *
+   * @param {string|null} displayName Display name.
+   * @param {string|null} email Email.
+   * @param {boolean} isAnonymous Is anonymous.
+   * @param {string} uid The user's unique ID.
+   * @param {function():Promise<void>} deleteUser Delete user callback.
+   */
+  constructor(displayName, email, isAnonymous, uid, deleteUser) {
+    if (!uid) {
+      throw new Error('uid must be provided.');
+    } else if (typeof uid !== 'string') {
+      throw new Error('uid should be a string.');
+    } else {
+      this._uid = uid;
+    }
+
+    if (!deleteUser) {
+      throw new Error('deleteUser must be provided.');
+    } else if (typeof deleteUser !== 'function') {
+      throw new Error('deleteUser should be a function.');
+    } else {
+      this._deleteUser = deleteUser;
+    }
+
+    this._displayName = displayName;
+    this._email = email;
+    this._isAnonymous = isAnonymous;
+  }
+
+  get displayName() {
+    return this._displayName;
+  }
+
+  get email() {
+    return this._email;
+  }
+
+  get isAnonymous() {
+    return this._isAnonymous;
+  }
+
+  get uid() {
+    return this._uid;
+  }
+
+  async delete() {
+    await delay(Constants.defaultDelayInMilliseconds);
+
+    await this._deleteUser();
+  }
+}
+
+export default User;