plugin.js

const path = require('path');

module.exports = (on, config, fs) => {
  // `on` is used to hook into various events Cypress emits
  // `config` is the resolved Cypress config
  const mocksFolder = path.resolve(config.fixturesFolder, '../mocks');

  const readFile = (filePath) => {
    if (fs.existsSync(filePath)) {
      return JSON.parse(fs.readFileSync(filePath, 'utf8'));
    }

    return null;
  };

  const deleteFile = (filePath) => {
    if (fs.existsSync(filePath)) {
      fs.unlinkSync(filePath);
      return true;
    }

    return null;
  };

  const cleanMocks = () => {
    // TODO: create error handling
    const specFiles = fs.readdirSync(config.integrationFolder);
    const mockFiles = fs.readdirSync(mocksFolder);
    mockFiles.forEach(mockName => {
      const isMockUsed = specFiles.find(specName => specName.split('.')[0] === mockName.split('.')[0]);
      if (!isMockUsed) {
        const mockData = readFile(path.join(mocksFolder, mockName));
        Object.keys(mockData).forEach(testName => {
          mockData[testName].forEach((route) => {
            if (route.fixtureId) {
              deleteFile(path.join(config.fixturesFolder, `${route.fixtureId}.json`));
            }
          });
        });

        deleteFile(path.join(mocksFolder, mockName));
      }
    });

    return null;
  };

  const removeAllMocks = () => {
    const fixtureFiles = fs.readdirSync(config.fixturesFolder);
    const mockFiles = fs.readdirSync(mocksFolder);

    fixtureFiles.forEach(fileName => {
      deleteFile(path.join(config.fixturesFolder, fileName));
    });

    mockFiles.forEach(fileName => {
      deleteFile(path.join(mocksFolder, fileName));
    });

    return null;
  };

  on('task', {
    readFile,
    deleteFile,
    cleanMocks,
    removeAllMocks,
  });
};