chart/tests/e2e/chart.test.mjs

/**
 * The chart shows the right window, at the right density, without throwing.
 *
 * Every assertion here failed at some point on 2026-08-10 while all 96 Python
 * tests passed, which is the whole argument for this file existing.
 */
import { test } from 'node:test';
import assert from 'node:assert/strict';
import {
  withChart, launch, openChart, chartState, selectTimeframe, assertNoPageErrors,
} from './helpers.mjs';

const TIMEFRAMES = ['1m', '5m', '15m', '30m', '1h', '1d'];

test('a first-time browser exchanges the friendly password for a session',
  { timeout: 180000 }, async () => {
    const { browser, page } = await launch();
    let statusRequests = 0;
    let submitted = null;
    try {
      page.on('dialog', async dialog => {
        assert.equal(dialog.message(), 'Password for this chart');
        await dialog.accept('friendly passphrase');
      });
      await page.route('**/api/status', async route => {
        statusRequests += 1;
        if (statusRequests === 1) await route.fulfill({ status: 401, body: '{}' });
        else await route.continue();
      });
      await page.route('**/api/login', async route => {
        submitted = route.request().postDataJSON();
        await route.fulfill({
          status: 204,
          headers: { 'set-cookie': 'chart-session=test; Path=/; HttpOnly; SameSite=Strict' },
        });
      });

      await openChart(page);

      assert.deepEqual(submitted, { password: 'friendly passphrase' });
      assert.ok(statusRequests >= 2, 'status was not retried after login');
      const unexpected = page.__errors.filter(error =>
        !error.includes('server responded with a status of 401'));
      assert.deepEqual(unexpected, [], `page errors: ${unexpected.join('; ')}`);
    } finally {
      await browser.close();
    }
  });

test('an existing browser token is migrated once and removed from local storage',
  { timeout: 180000 }, async () => {
    const { browser, page } = await launch();
    let presentedToken = null;
    try {
      await page.addInitScript(() => localStorage.setItem('chart-token', 'legacy-token'));
      await page.route('**/api/login', async route => {
        presentedToken = route.request().headers()['x-chart-token'];
        await route.fulfill({
          status: 204,
          headers: { 'set-cookie': 'chart-session=test; Path=/; HttpOnly; SameSite=Strict' },
        });
      });

      await openChart(page);

      assert.equal(presentedToken, 'legacy-token');
      assert.equal(await page.evaluate(() => localStorage.getItem('chart-token')), null);
      assertNoPageErrors(page, assert);
    } finally {
      await browser.close();
    }
  });

test('the viewport opens on the live edge, not in the past', { timeout: 180000 }, async () => {
  await withChart(async page => {
    const state = await chartState(page);
    assert.ok(state.bars > 0, 'the chart loaded no bars at all');
    // The bug: setBars placed the viewport by logical index, and the daily MA
    // series then prepended hundreds of points, sliding the view ~10 hours back
    // while the data itself was perfectly current.
    assert.equal(
      state.visibleTo, state.lastTime,
      'the newest bar is not the right-hand edge of the viewport',
    );
    assertNoPageErrors(page, assert);
  });
});

test('the status row shows the exact local time data last arrived',
  { timeout: 180000 }, async () => {
    await withChart(async page => {
      await page.waitForFunction(() => {
        const freshness = document.querySelector('.data-freshness b');
        return freshness?.textContent.trim() !== '—';
      });
      const state = await page.evaluate(() => {
        const freshness = document.querySelector('.data-freshness');
        return {
          freshness: freshness.textContent.trim(),
          deployMetadata: document.querySelector('.app-meta'),
          barHeight: document.querySelector('.statusbar').getBoundingClientRect().height,
        };
      });
      assert.match(state.freshness, /^UPDATED\s+\d{1,2}:\d{2}:\d{2}\s*(AM|PM)?$/i);
      assert.equal(state.deployMetadata, null);
      assert.ok(state.barHeight <= 40, `status bar grew to ${state.barHeight}px`);
      assertNoPageErrors(page, assert);
    });
  });

test('a daily crosshair shows the session date, not the previous evening',
  { timeout: 180000 }, async () => {
    await withChart(async page => {
      await selectTimeframe(page, '1d');
      const state = await page.evaluate(() => {
        const c = window.__chart;
        const time = c.bars[c.bars.length - 1].t;
        return {
          actual: c.chart.options().localization.timeFormatter(time),
          expected: new Date(time * 1000).toLocaleString(undefined, {
            timeZone: 'UTC', year: 'numeric', month: 'short', day: 'numeric',
          }),
        };
      });
      assert.equal(state.actual, state.expected);
      assert.doesNotMatch(state.actual, /\d:\d/);
      assertNoPageErrors(page, assert);
    });
  });

test('every timeframe gives one slot per candle', { timeout: 300000 }, async () => {
  await withChart(async page => {
    for (const tf of TIMEFRAMES) {
      await selectTimeframe(page, tf);
      const state = await chartState(page);
      // The bug: a minute-resolution VWAP put its own points on the shared time
      // scale, so an hourly chart spread 160 candles over 908 slots and drew
      // them as slivers. Anything much above 1.0 means the scale is polluted.
      const ratio = state.slots / Math.max(state.inView, 1);
      assert.ok(
        ratio > 0.8 && ratio < 1.3,
        `${tf}: ${state.inView} candles spread over ${state.slots} slots (ratio ${ratio.toFixed(2)})`,
      );
    }
    assertNoPageErrors(page, assert);
  });
});

test('switching timeframes rapidly never throws', { timeout: 300000 }, async () => {
  await withChart(async page => {
    // The bug: bar events for the timeframe just left arrived after the new
    // snapshot, and Lightweight Charts throws "Cannot update oldest data"
    // rather than ignoring a stale bar, which took the whole app down.
    for (let round = 0; round < 3; round += 1) {
      for (const tf of ['1m', '1h', '15m', '1d', '5m']) {
        await page.click(`.timeframes button:text-is("${tf}")`);
        await page.waitForTimeout(700);
      }
    }
    await page.waitForTimeout(2000);
    const state = await chartState(page);
    assert.ok(state.bars > 0, 'the chart lost its data while switching');
    assertNoPageErrors(page, assert);
  });
});