单元测试true和false的变量 [英] Unit test a variable for both true and false

问题描述

我在这里使用googletest / googlemock来处理C ++生产代码。我在使用A.cpp中的一个函数时遇到了这个想法：

  bool A :: process_ ）; 
 
 bool A :: process（）
 {
 if（！process_）{
 process_ = true; 
} 
 return process_; 
} 
  

其中标题包含：

  protected：
 static bool process_; 
 public：
 static bool process（）; 
  

我卡住的方式，我只能测试函数的期望输出true或输入假如：

  TEST（ATest，processVal）{
 
 A a; 
 EXPECT_TRUE（a.process（））; 
 
} 
  

有一种方法来测试函数， code> * true * 和 * false * 值 process _ ？所以测试覆盖了两者的决定。
我想嘲笑，所以它可以期望一个调用true和false，但因为它不是一个类的成员函数，我想你不能做嘲笑process_吗？
如果可以，如何模拟变量？

注意：我在linux和gcc :)谢谢！ b

解决方案

• 解决方案1：访问任何 protected

您可以轻松地修改 _process 即使受保护，只要这样做：

  class SubA：public A 
 {
 public：
 void setProcess（bool val）{process_ = val; } 
}; 
 
 A a; 
 SubA * pA =（SubA *）& a; 
 pA-> setProcess（false）; 
  

这将工作得很好，是安全的。即使你把 A * 转换为 SubA * 这不是真正有效，它将作为 SubA 对象与 A 对象相同（ SubA 。

这只有工作原因，因为 process _ 是 protected ，所以你创建一个派生类 SubA 并使用它，因为编译器将允许这个子类访问受保护的东西。

• 解决方案2：要访问任何 protected ，甚至 $
$ b $ c> process _ 是 private ，这不会工作...但是， private / protected 仅由编译器管理...属性在内存中，即使您不是允许也可以访问它们。
  
  
  

  这是丑陋，但工作完美：

    #define protected public 
   #define private public 
   #includeAh
   #undef private 
   #undef protected 
   
   {
   A a; 
   a._process = false; 
  } 
    

  这个黑客可以轻松访问任何 / code> / protected 属性/函数。

  
  

  I'm working on a C++ production code here with googletest/googlemock. I've stumble upon this idea when working with one of the function in A.cpp:

  bool A::process_(false);
  
  bool A::process()
  {
      if ( !process_ ){
          process_ = true;
      }
  return process_;
  }
  

  where the header contains:

  protected:
      static bool process_;
  public:
      static bool process();
  

  I am stuck in a way that I can only test the function for an expected output of true or an input of false like so:

  TEST(ATest, processVal){
  
      A a;
      EXPECT_TRUE(a.process());
  
  }
  

  Is there a way to test the function so that both *true* and *false* value of process_ is passed ? So that the test covers the decision for both. I was thinking mocking so that it can expect a call for both true and false but because it is not a function in a member of a class, I guess you can not do mocking for process_ ? If you can, how to mock the variable?

  Note: I'm on linux and gcc :) thank you !

  解决方案

  • Solution1: To access any protected attribute/method from a test without modifying production code

  You can easily modify _process even if protected, just do this:

  class SubA : public A
  {
  public:
      void setProcess( bool val ) { process_ = val; }
  };
  
  A a;
  SubA* pA = (SubA*) &a;
  pA->setProcess( false );
  

  This will work pretty well and is safe. Even if you are casting A* to SubA* which is not really valid, it will work as SubA objects in memory are the same as A objects (as SubA does not declare any extra attribute).

  This only works because process_ is protected, so you create a derived class SubA and use it because compiler will allow this subclass to access the protected stuff.

  • Solution2: To access any protected and even private attribute/method from a test without modifying production code

  Now, if process_ was private, this would not work...but, private/protected is only managed by the compiler...the attributes are here in memory and you may access them even if you are not "allowed to".

  It's ugly but works perfectly:

  #define protected public
  #define private public
  #include "A.h"
  #undef private
  #undef protected
  
  {
      A a;
      a._process = false;
  }
  

  This hack makes it easy to access any private/protected attributes/functions from your test programs.

  这篇关于单元测试true和false的变量的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！