LUMIERA.clone/tests/library/ios-savepoint-test.cpp

/*
  IosSavepoint(Test)  -  manipulate and restore output stream formatting

   Copyright (C)
     2022,            Hermann Vosseler <Ichthyostega@web.de>

  **Lumiera** is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by the
  Free Software Foundation; either version 2 of the License, or (at your
  option) any later version. See the file COPYING for further details.

* *****************************************************************/

/** @file ios-savepoint-test.cpp
 ** unit test \ref IosSavepoint_test
 */


#include "lib/test/run.hpp"
#include "lib/format-cout.hpp"
#include "lib/ios-savepoint.hpp"

#include <iomanip>
#include <string>


using std::string;


namespace util {
namespace test {
  
  
  
  
  /***************************************************************************//**
   * @test verifies capturing and restoring of std::ostream formatting state.
   * @see ios-savepoint.hpp
   */
  class IosSavepoint_test
    : public Test
    {
      void
      run (Arg)
        {
          switchToHex();
          __verifySane();
          
          setFill();
          __verifySane();
          
          nested();
          __verifySane();
          
          try {
            restoreAfterException();
          } catch(...){
            cout << "Tilt" <<endl;
          }
          __verifySane();
        }
      
      
      /** verify that original state is restored */
      void
      __verifySane()
        {
          cout << std::setw(10) << 42 <<endl;
        }
      
      
      /** @test verify that hexadecimal output is cleared  */
      void
      switchToHex()
        {
          IosSavepoint save{cout};
          cout << std::hex
               << std::showbase
               << 42 <<endl;
        }
      
      
      /** @test verify that a custom fill character is cleared */
      void
      setFill()
        {
          IosSavepoint save{cout};
          cout << std::setfill('*')
               << std::setw(20)
               << 42 <<endl;
        }
      
      
      /** @test verify usage in nested scopes */
      void
      nested()
        {
          IosSavepoint save{cout};
          cout << std::hex << 42 <<endl;
          {
            IosSavepoint inner(cout);
            cout << std::oct << std::showbase << 42 <<endl;
          }
          cout << 42 <<endl;
        }
      
      
      /** @test verify clean-up happens even in case of an exception */
      void
      restoreAfterException()
        {
          auto boom = []() -> float
                      { throw 42; };
          
          IosSavepoint save{cout};
          cout << std::hexfloat
               << 1234
               << endl
               << boom()
               << endl;
        }
    };
  
  LAUNCHER (IosSavepoint_test, "unit common");
  
  
}} // namespace util::test