Mock CSV file in Vitest

mock-csv.test.ts

import { vi, describe, test, expect } from 'vitest';

// Mock CSV content
const mockCSVContent = `id,name,age
1,John Doe,30
2,Jane Smith,25
3,Bob Johnson,45`;

describe('CSV File Object Creation', () => {
  test('creates a File object with CSV content', () => {
    // Create a mock File object
    const mockFile = new File([mockCSVContent], 'test.csv', { type: 'text/csv' });

    // Assertions
    expect(mockFile).toBeInstanceOf(File);
    expect(mockFile.name).toBe('test.csv');
    expect(mockFile.type).toBe('text/csv');

    // Read the file content
    return new Promise((resolve) => {
      const reader = new FileReader();
      reader.onload = (event) => {
        const content = event.target.result;
        expect(content).toBe(mockCSVContent);
        resolve();
      };
      reader.readAsText(mockFile);
    });
  });

  test('simulates file upload with mock CSV File', async () => {
    const mockFile = new File([mockCSVContent], 'test.csv', { type: 'text/csv' });

    // Simulate file upload function
    const uploadFile = async (file) => {
      return new Promise((resolve) => {
        const reader = new FileReader();
        reader.onload = (event) => {
          const content = event.target.result;
          resolve({ success: true, content });
        };
        reader.readAsText(file);
      });
    };

    const result = await uploadFile(mockFile);
    expect(result.success).toBe(true);
    expect(result.content).toBe(mockCSVContent);
  });
});