feat: split Install/UnitTest stages, add game.js tests with 100% coverage

21 tests covering win/loss/draw/score/reset. lcov report fed to SonarQube.
Pipeline: Install → Unit Test → Scan Code Quality → Build & Push.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

test/game.test.js

@@ -0,0 +1,157 @@
+/**
+ * @jest-environment jsdom
+ */
+
+function setupDOM() {
+  document.body.innerHTML = `
+    <div id="status">Player X's turn</div>
+    <div id="board">
+      ${Array.from({ length: 9 }, (_, i) => `<div class="cell" data-index="${i}"></div>`).join('')}
+    </div>
+    <span id="score-x">0</span>
+    <span id="score-draw">0</span>
+    <span id="score-o">0</span>
+    <button id="reset">New Game</button>
+  `;
+}
+
+function click(index) {
+  document.querySelectorAll('.cell')[index].dispatchEvent(new MouseEvent('click', { bubbles: true }));
+}
+
+function reset() {
+  document.getElementById('reset').dispatchEvent(new MouseEvent('click', { bubbles: true }));
+}
+
+beforeEach(() => {
+  setupDOM();
+  jest.resetModules();
+  require('../public/game.js');
+});
+
+describe('initial state', () => {
+  test('all cells empty', () => {
+    document.querySelectorAll('.cell').forEach(c => expect(c.textContent).toBe(''));
+  });
+
+  test('status shows X turn', () => {
+    expect(document.getElementById('status').textContent).toBe("Player X's turn");
+  });
+
+  test('scores start at 0', () => {
+    expect(document.getElementById('score-x').textContent).toBe('0');
+    expect(document.getElementById('score-o').textContent).toBe('0');
+    expect(document.getElementById('score-draw').textContent).toBe('0');
+  });
+});
+
+describe('turn alternation', () => {
+  test('alternates X and O after each move', () => {
+    click(0);
+    expect(document.getElementById('status').textContent).toBe("Player O's turn");
+    click(1);
+    expect(document.getElementById('status').textContent).toBe("Player X's turn");
+  });
+
+  test('cell shows correct player mark', () => {
+    click(0);
+    expect(document.querySelectorAll('.cell')[0].textContent).toBe('X');
+    click(1);
+    expect(document.querySelectorAll('.cell')[1].textContent).toBe('O');
+  });
+
+  test('clicking taken cell does nothing', () => {
+    click(0);
+    click(0);
+    expect(document.getElementById('status').textContent).toBe("Player O's turn");
+  });
+});
+
+describe('X wins', () => {
+  // X: 0,1,2  O: 3,4
+  beforeEach(() => { click(0); click(3); click(1); click(4); click(2); });
+
+  test('status shows X wins', () => {
+    expect(document.getElementById('status').textContent).toBe('Player X wins!');
+  });
+
+  test('winning cells get winner class', () => {
+    const cells = document.querySelectorAll('.cell');
+    expect(cells[0].classList.contains('winner')).toBe(true);
+    expect(cells[1].classList.contains('winner')).toBe(true);
+    expect(cells[2].classList.contains('winner')).toBe(true);
+  });
+
+  test('X score increments', () => {
+    expect(document.getElementById('score-x').textContent).toBe('1');
+  });
+
+  test('no moves accepted after win', () => {
+    click(5);
+    expect(document.querySelectorAll('.cell')[5].textContent).toBe('');
+  });
+});
+
+describe('O wins', () => {
+  // X: 0,6,7  O: 3,4,5
+  beforeEach(() => { click(0); click(3); click(6); click(4); click(7); click(5); });
+
+  test('status shows O wins', () => {
+    expect(document.getElementById('status').textContent).toBe('Player O wins!');
+  });
+
+  test('O score increments', () => {
+    expect(document.getElementById('score-o').textContent).toBe('1');
+  });
+});
+
+describe('draw', () => {
+  // X: 0,2,5,6,7  O: 1,3,4,8 — fills board, no winner
+  beforeEach(() => {
+    click(0); click(1); click(2); click(3); click(5); click(4); click(6); click(8); click(7);
+  });
+
+  test('status shows draw', () => {
+    expect(document.getElementById('status').textContent).toBe("It's a draw!");
+  });
+
+  test('draw score increments', () => {
+    expect(document.getElementById('score-draw').textContent).toBe('1');
+  });
+});
+
+describe('reset', () => {
+  test('clears board after game', () => {
+    click(0); click(1);
+    reset();
+    document.querySelectorAll('.cell').forEach(c => expect(c.textContent).toBe(''));
+  });
+
+  test('resets status to X turn', () => {
+    click(0);
+    reset();
+    expect(document.getElementById('status').textContent).toBe("Player X's turn");
+  });
+
+  test('score persists across reset', () => {
+    click(0); click(3); click(1); click(4); click(2);
+    reset();
+    expect(document.getElementById('score-x').textContent).toBe('1');
+  });
+
+  test('allows play after reset', () => {
+    click(0); click(1); click(2); click(3); click(4); click(5); click(6); click(7); click(8);
+    reset();
+    click(0);
+    expect(document.querySelectorAll('.cell')[0].textContent).toBe('X');
+  });
+});
+
+describe('score accumulates across games', () => {
+  test('multiple wins tracked', () => {
+    click(0); click(3); click(1); click(4); click(2);
+    reset();
+    click(0); click(3); click(1); click(4); click(2);
+    expect(document.getElementById('score-x').textContent).toBe('2');
+  });
+});