React Login Series - Login Feature Complete Test Suite | Part 6b

Login Feature Test Suite Overview

The Login Feature in our React application has been tested across multiple layers to ensure robustness, correctness, and maintainability. Tests cover UI behavior, routing logic, service integration, state management, and event emission. We classify tests into four primary types:

Test Style Purpose Contract Test Locks down public guarantees of the AuthContext API for consumers, such as expected return values from login, logout, /me resolution, and event emission. Behavior Test Validates internal mechanics of AuthContext and components, like password toggle, loader visibility, and input updates. Unit Test Isolates single functions such as resetPassword, verifyEmailAccount, or requestPasswordResetApi to confirm correct outputs and error handling. Integration Test Tests multiple pieces working together, such as login → /me → state update → event emission → logout, simulating realistic usage flows.

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File-Level Test Breakdown

1. LoginPage.test.jsx — UI & Form Behavior

Tests the Login Page component directly, covering interactions and visibility of inputs and buttons.

Test Name Purpose renders email and password inputs Ensures both fields are present in the DOM. allows typing into email and password fields Confirms controlled inputs update state correctly. toggles password visibility Verifies show/hide password button works and updates input type. signin button is disabled when values are missing Checks that form validation prevents submission with incomplete input. shows signed-in message Confirms AuthContext’s authMessage appears after login. shows error message Confirms error messages render correctly when login fails. finds inputs via document.getElementById Ensures inputs are properly attached to DOM nodes for legacy references.

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1. ProtectedRoute.test.jsx — Routing & Guard Behavior

Ensures public and private routes enforce authentication rules correctly.

Test Name Purpose redirects unauthenticated user to login Validates that protected routes redirect to /login when authuser is null. renders fallback GuardLoader Confirms loader is shown while authReady is false.

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1. AuthContext.test.tsx — Contract, Behavior, and Service Integration

Focuses on AuthContext itself, testing state transitions, service interactions, and edge cases.

Test Name Purpose sets authuser when /me succeeds Ensures session bootstrap correctly sets user identity. sets authuser to null when unauthenticated Confirms failed /me returns null. logs in and resolves session via /me Verifies login flow updates state and sets success message. clears authuser on logout Ensures logout destroys session and sets success message. throws when passwords do not match Validates resetPassword rejects mismatched passwords. calls confirmPasswordResetApi and sets success message Confirms password reset interacts with API and updates authMessage. sets error message when API returns failure Confirms API errors are caught and reflected in authMessage. handles service failures Verifies proper error handling for JSON errors, invalid tokens, or reCAPTCHA failures. 4. AuthContextEvents.test.tsx — Event Emission & Integration Flow

Tests end-to-end behavior of AuthContext in combination with the Auth Telemetry service.

Test Name Purpose emits events and handles login → logout flow Ensures emitAuthEvent is called at key points (login, /me resolution, logout) and state updates correctly. 5. Additional Test Coverage

To maximize coverage and robustness, the following tests were added or recommended:

Test Type Purpose State transition tests Ensures AuthContext state updates in correct order: authReady, authuser, authMessage. Negative routing tests Confirms protected routes redirect or block access under unauthorized conditions. Event emission tests Verifies emitAuthEvent triggers for login, logout, password_reset_submit, verify_email. Idempotency tests Ensures repeated calls to login/logout/reset password do not produce side effects or inconsistent state. End-to-end integration flow (non-Cypress) Simulates user flow: login → /me → AuthContext state → logout → state cleared.

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AuthContext & Login Flow

flowchart TD
    A[Login Page Render] --> B[User enters email & password]
    B --> C[Login Button Click]
    C --> D[loginApi called]
    D --> E[/me API called]
    E --> F{success?}
    F -->|yes| G[authuser set, authMessage "success"]
    F -->|no| H[authuser null, authMessage "error"]
    G --> I[emitAuthEvent("user_login")]
    H --> I
    I --> J[Password Reset / Verify Email flows (optional)]
    G --> K[User clicks Logout]
    K --> L[logoutApi called]
    L --> M[resolveSession()]
    M --> N[authuser cleared, authMessage "logged out"]
    N --> O[emitAuthEvent("user_logout")]

Summary:

Our test suite now covers:

1. UI component behavior (LoginPage.test.jsx)
2. Routing & protected route logic (ProtectedRoute.test.jsx)
3. AuthContext contract, state management, and API interactions (AuthContext.test.tsx)
4. Event emission and full login/logout integration (AuthContextEvents.test.tsx)
5. Service error handling and edge cases
6. Password reset, email verification, and reCAPTCHA failure paths
7. Max coverage achieved by combining contract, behavior, unit, and integration tests

This suite ensures robust, predictable login behavior and allows safe refactoring while guaranteeing public API contracts remain intact.