为什么这个(琐碎的)单元测试失败了？

Question

这几乎是从IBM的Mastering Grails系列中逐字记录下来的.

DateTagLib.groovy:

class DateTagLib {
  def thisYear = {
    out << Calendar.getInstance().get(Calendar.YEAR)
  }
}

DateTagLibTests.groovy:

class DateTagLibTests extends TagLibUnitTestCase {
    def dateTagLib

    protected void setUp() {
        super.setUp()

        dateTagLib = new DateTagLib()
    }

    void testThisYear() {
        String expected = Calendar.getInstance().get(Calendar.YEAR)
        assertEquals("years do NOT match", expected, dateTagLib.thisYear())
    }

    protected void tearDown() {
        super.tearDown()
    }
}

grails test-app DateTagLib 输出:

-------------------------------------------------------
Running 1 unit test...
Running test DateTagLibTests...
                    testThisYear...FAILED
Tests Completed in 359ms ...
-------------------------------------------------------
Tests passed: 0
Tests failed: 1
-------------------------------------------------------

我尝试匹配类型(int/long/String),但我仍然撞在墙上.

此测试也失败了:

void testThisYear() {
    long expected = Calendar.getInstance().get(Calendar.YEAR)
    assertEquals("years do NOT match", expected, (long) dateTagLib.thisYear())
}

Answer 1

请尝试以下方法

class DateTagLibTests extends TagLibUnitTestCase {

    void testThisYear() {
        String expected = Calendar.getInstance().get(Calendar.YEAR)
        tagLib.thisYear()
        assertEquals("years do NOT match", expected, tagLib.out)
    }

}

您的原始代码有2个问题:

• 你不应该DateTagLib明确地实例化.它已通过名为的测试类的属性提供tagLib
• thisYear它不会返回年份值,而是将其写入out.在测试中,您可以访问写入输出的内容tagLib.out