Question

I have a parent class test with child classes that are sub-tests. When I call test->run() I want to run all my sub tests. The code below does not work b.c. the child class is not recognized in the parent class.

using namespace std;
  class test
    {
    protected:
      short verbosity_;
    public:
      void setVerbosity(short v)
        {
        if((v==0 || v==1 || v==2)) 
          {
          verbosity_ = v;
          }
        else 
          {
          cout << " Verbosity Level Invalid " << endl;
          }
        }
      void run()
        {
        natives natives_1; // this does not work
      }
    };
  class natives : public test 
    {
    public:
      natives()
        {
        this->run();
        }
      void run()
       {
       testInts<short>();
       testInts<int>();
       testInts<long>();
       testInts<unsigned short>();
       testInts<unsigned int>();
       testInts<unsigned long>();
       }         
    protected:
      template<class T> void testFloats()
        {
        }
      template<class T> void testInts()
        {
        short passState, bitDepth;
        T failMax, pow2 = 1, minValue = 0, maxValue = 0, bitCount = 0, failValue = 0;  
        const char* a = typeid(T).name();
        bool signedType = ((*a == 't') || (*a == 'j') || (*a == 'm'));
        while(pow2 > 0)
          {
          pow2 *= 2;
          bitCount++;
          }
        maxValue = pow2-1;
        failValue = pow2;
        int native1 = bitCount;
        int native2 = sizeof(T)*8;
        int native3 = numeric_limits<T>::digits;  
        if( !signedType )
          {
          native1++;
          native3++;
          }       
        if(verbosity_>=1) cout << endl << "**********\n" << reportType(a) << "\n**********" << endl << endl;
        if ((native1 == native2) && (native1 == native3))
          {
          if(verbosity_>=1)cout << "Correlation:\t\tPass: " << native1 << endl ;
          if(verbosity_>=2)
          {
            cout << "--Algorithm:\t\t" << native1 << endl;
            cout << "--Sizeof:\t\t" << native2 << endl;
            cout << "--Reported:\t\t" << native3 << endl;
            cout << "----Max Value:\t\t" << maxValue << endl;
            cout << "----Max+1\t\t" << failValue << endl;
            } 
         else
            {
            }
          }
        else
          {
          cout << "Correlation:\t\tFail" << endl ;
          }
        }
      string reportType(const char* c1)
        { 
        string s1;
        switch(*c1)
          {
          case 't':
            s1 = "Unsigned short";
            break;
          case 'j':
            s1 = "Unsigned int";
            break;
          case 'm':
            s1 = "Unsigned long";
            break;
          case 's':
            s1 = "Short";
            break;
          case 'i':
            s1 = "Int";
            break;
          case 'l':
            s1 = "Long";
            break;
          default:
            s1 = "Switch failed";
          }
        return s1;
        }
};

Answer 1

Probably a better way to do it would be to make a pure virtual function called run in the test class, and then the tests of the subclass will implement it and those will be run when you call run on an instance of the subclass.

For instance:

class Test {
public:
    virtual void run() = 0;

    void setVerbosity(short v) {
        if((v==0 || v==1 || v==2)) 
            verbosity_ = v;
        else
            cout << " Verbosity Level Invalid " << endl;
    }
};

class Natives : public Test {
public:
    void run() {
        // do all the tests....
    }
};

Then you can do

Natives n;
n.run();

And they will still be run when you do it through a Test* (or Test&):

Test* t = new Natives;
t->run(); // runs Natives::run

You might also be able to use CRTP here but I think it’s unnecessary.