Question

我正在尝试改善此文件的测试范围

'use strict'

/**
 * Returns the logging options we're using
 *
 * @param   {String} name Name of the logger. Should be service name. e.g. ciitizen-file-service
 * @returns {Object}      The logging options we're using
 * @private
 */
function getLoggerOptions(name) {
  return {
    name: name,
    streams: [
      {
        level: 'info',
        stream: stdOutStream()
      }, {
        level: 'error',
        stream: stdErrStream()
      }
      , {
        level: 'debug',
        stream: stdOutStream()
      },
      {
        level: 'warn',
        stream: stdOutStream()
      },
      {
        level: 'fatal',
        stream: stdErrStream()
      }
    ]
  }
}

/**
 * Creates a stream that writes to stdout
 *
 * @param   {Object} info The log info
 * @returns {Object}      An object which logs to stdout
 * @private
 */
function stdOutStream() {
  return {
    write: log => {
      // Change log level number to name and write it out
      log.level = bunyan.nameFromLevel[log.level]
      process.stdout.write(JSON.stringify(log) + '\n')
    }
  }
}

/**
 * Creates a stream that writes to stderr
 *
 * @param   {Object} info The log info
 * @returns {Object}      An object which logs to stderr
 * @private
 */
function stdErrStream() {
  return {
    write: log => {
      // Change log level number to name and write it out
      log.level = bunyan.nameFromLevel[log.level]
      process.stderr.write(JSON.stringify(log) + '\n')
    }
  }
}

module.exports = { getLoggerOptions }

我目前正在测试

'use strict'

const expect = require('chai').expect
const { getLoggerOptions } = require('../src/helpers')

describe.only('#getLoggerOptions', () => {
  it('should return the logger options', () => {
    expect(getLoggerOptions('test')).to.be.an('object')
  })
})

哪个会在单元测试覆盖率

中造成差距

我该如何编写测试以涵盖此代码？

Answer 1

您只是断言getLoggerOptions(...)应该返回一个对象，但您没有访问该对象。

例如，除了发布的测试外，尝试添加以下测试：

describe.only('#probeLoggerOptions', () => {
  it('should do expected logging stuff', () => {
    const {name, streams} = getLoggerOptions('test');
    for (let stream of streams) {
      console.log(`getting logopt for level ${stream.level}`);
      expect(stream.stream.write(log), /* ... what to expect */);
    }
  });
});

现在测试正在每个对象中调用write函数。

额外：如果您拥有代码，则最好的方法是将其重构为更具可测试性。例如，您可以创建一个process，然后对其进行写入，然后通过管道传输到所需的WritableStream流，而不是直接写入高级process流。

function configureStream(writable = process.stdout, data = null, msg = 'done') {
  const stream = fs.createReadStream('/tmp/log');
  stream.read(data);
  stream.pipe(writable);

}

function stdOutStream() {
  return {
    write: log => {
      // Change log level number to name and write it out
      log.level = bunyan.nameFromLevel[log.level];
      configureStream(data = JSON.stringify(log) + '\n');
    }
  }
}

除了能够分别测试configureStream之外，您还可以将每个日志记录过程的内容抽象为一个减少测试面的函数。现在，您还可以加入流事件，例如“ pipe”或“ finish”，以检查正在记录的内容。

我该如何为使用stdout的东西编写测试？

1 个答案: