test: ensure custom metrics survive global updates

Author: JavaZeroo

src/App.jsx

@@ -171,17 +171,25 @@ function App() {
   const handleGlobalParsingConfigChange = useCallback((newConfig) => {
     setGlobalParsingConfig(newConfig);
 
-    // Sync parsing config to all files
-    setUploadedFiles(prev => prev.map(file => ({
-      ...file,
-      config: {
-        ...file.config,
-        metrics: newConfig.metrics.map(m => ({ ...m })),
-        useStepKeyword: newConfig.useStepKeyword,
-        stepKeyword: newConfig.stepKeyword
-      }
-    }))); 
-  }, []);
+    // Sync parsing config to files that still use the global metrics
+    setUploadedFiles(prev => prev.map(file => {
+      const fileConfig = file.config || {};
+      const usesGlobalMetrics = !fileConfig.metrics ||
+        JSON.stringify(fileConfig.metrics) === JSON.stringify(globalParsingConfig.metrics);
+
+      return {
+        ...file,
+        config: {
+          ...fileConfig,
+          ...(usesGlobalMetrics && {
+            metrics: newConfig.metrics.map(m => ({ ...m }))
+          }),
+          useStepKeyword: newConfig.useStepKeyword,
+          stepKeyword: newConfig.stepKeyword
+        }
+      };
+    }));
+  }, [globalParsingConfig]);
 
   // Reset configuration
   const handleResetConfig = useCallback(() => {

src/components/__tests__/GlobalConfigOverride.test.jsx

@@ -0,0 +1,94 @@
+import React from 'react';
+import { render, screen, within, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { describe, it, expect, beforeEach, vi } from 'vitest';
+import '@testing-library/jest-dom/vitest';
+import App from '../../App.jsx';
+import i18n from '../../i18n';
+
+// Mock chart.js and react-chartjs-2 to avoid canvas requirements
+vi.mock('chart.js', () => {
+  const Chart = {
+    register: vi.fn(),
+    defaults: { plugins: { legend: { labels: { generateLabels: vi.fn(() => []) } } } }
+  };
+  return {
+    Chart,
+    ChartJS: Chart,
+    CategoryScale: {},
+    LinearScale: {},
+    PointElement: {},
+    LineElement: {},
+    Title: {},
+    Tooltip: {},
+    Legend: {},
+  };
+});
+
+vi.mock('react-chartjs-2', async () => {
+  const React = await import('react');
+  return {
+    Line: React.forwardRef(() => <div data-testid="line-chart" />)
+  };
+});
+
+vi.mock('chartjs-plugin-zoom', () => ({ default: {} }));
+
+function stubFileReader(result) {
+  class FileReaderMock {
+    constructor() {
+      this.onload = null;
+    }
+    readAsText() {
+      this.onload({ target: { result } });
+    }
+  }
+  global.FileReader = FileReaderMock;
+}
+
+describe('Global config override', () => {
+  beforeEach(() => {
+    localStorage.clear();
+  });
+
+  it('retains file metric config after global change', async () => {
+    stubFileReader('train_loss: 1');
+    const user = userEvent.setup();
+
+    render(<App />);
+
+    const input = screen.getByLabelText(i18n.t('fileUpload.aria'));
+    const file = new File(['train_loss: 1'], 'a.log', { type: 'text/plain' });
+    await user.upload(input, file);
+
+    await screen.findByText('a.log');
+
+    const configBtn = screen.getByLabelText(i18n.t('fileList.config', { name: 'a.log' }));
+    await user.click(configBtn);
+
+    const modal = screen.getByRole('dialog');
+    const keywordInputs = within(modal).getAllByPlaceholderText('keyword');
+    await user.clear(keywordInputs[0]);
+    await user.type(keywordInputs[0], 'train_loss:');
+
+    const saveBtn = screen.getByText(i18n.t('configModal.save'));
+    await user.click(saveBtn);
+
+    await waitFor(() => expect(screen.queryByRole('dialog')).not.toBeInTheDocument());
+
+    // Update global config
+    const globalKeyword = screen.getAllByPlaceholderText('keyword')[0];
+    await user.clear(globalKeyword);
+    await user.type(globalKeyword, 'val_loss:');
+    expect(globalKeyword.value).toBe('val_loss:');
+
+    // Reopen file config to verify keyword remains
+    const configBtn2 = screen.getByLabelText(i18n.t('fileList.config', { name: 'a.log' }));
+    await user.click(configBtn2);
+
+    const modal2 = screen.getByRole('dialog');
+    const updatedInputs = within(modal2).getAllByPlaceholderText('keyword');
+    expect(updatedInputs[0].value).toBe('train_loss:');
+  });
+});
+