android中单元測试中的断言assert的使用与扩展

首先看一组对照，比方说我们要測试的结果是一个Linearlaout  

• AssertJ Android:

  assertThat(layout).isVisible()
      .isVertical()
      .hasChildCount(4)
      .hasShowDividers(SHOW_DIVIDERS_MIDDLE);
  

• Regular JUnit:

  assertEquals(View.VISIBLE, layout.getVisibility());
  assertEquals(VERTICAL, layout.getOrientation());
  assertEquals(4, layout.getChildCount());
  assertEquals(SHOW_DIVIDERS_MIDDLE, layout.getShowDividers());
  

• Regular AssertJ:

  assertThat(layout.getVisibility()).isEqualTo(View.VISIBLE);
  assertThat(layout.getOrientation()).isEqualTo(VERTICAL);
  assertThat(layout.getChildCount()).isEqualTo(4);
  assertThat(layout.getShowDividers()).isEqualTo(SHOW_DIVIDERS_MIDDLE);

从形式上。使用上更加方便。

从输出结果上看，输出结果更加直接可见。

• AssertJ Android:     Expected visibility <gone> but was <invisible>.

• Regular JUnit          Expected:<[8]> but was:<[4]>

• Regular AssertJ:     Expected: <8> but was: <4>

所以接下来我们来看看  Assert Android怎样来使用。

1首先写一个待測试的数据结构

 public class Draft{

      private String id;//草稿的唯一标识id 
      private String uid ;//发送账号uid，以差别不同账号的草稿
      private int type;//保存的类型

      private String displayedTitle;//展示标题内容

}

2 首先我们来自己定义一个断言类:

   public class DraftAssert extends AbstractAssert<DraftAssert ,Draft>{

      public DraftAssert (Draft draft){

       super(draft,DraftAssert.class);}

}   

   public static DraftAssert  assertThat(Draft draft){

      return new DraftAssert (draft);}

   public DraftAssert  hasDisplayedName(String name){

      isNotNull();

      if (!draft.getDisplayedTitle().equals(name)){

      failWithMessage(("Expected character's name to be <%s> but was <%s>", name, draft.getDisplayedTitle());)

      return this;

}

}

3、使用的时候

     DraftAssert.assertThat(draft).hasDisplayedName("@罗浩");

     假设导入DraftAssert.assertThat静态导入的话，你还能够直接使用

     assertThat(draft).hasDisplayedName("@罗浩");