an object to change the IMessagePrinter temporarily More...

#include <MessagePrinterOverlay.h>

Collaboration diagram for asg::MessagePrinterOverlay:

Public Member Functions
	MessagePrinterOverlay (IMessagePrinter *val_printer) noexcept
	overlay with the given message printer
	~MessagePrinterOverlay () noexcept
	remove the currently overlaid printer

Static Public Member Functions
static IMessagePrinter &	current () noexcept
	get the current IMessagePrinter

Private Member Functions
	MessagePrinterOverlay (MessagePrinterOverlay &)=delete
MessagePrinterOverlay	operator= (MessagePrinterOverlay &)=delete

Static Private Member Functions
static IMessagePrinter *&	getCurrent () noexcept
	get a reference to the pointer to the current IMessagePrinter

Private Attributes
IMessagePrinter *	m_saved = nullptr
	the stored message printer we need to restore
IMessagePrinter *	m_current = nullptr
	the current message printer we should have when we restore

Detailed Description

an object to change the IMessagePrinter temporarily

The idea is to use this in unit tests to replace the standard printer with a mock object. The idea is to place this on the stack and it will then replace the standard object for as long as it is on the stack.

Note that this is per se not thread-safe, but given the intended purpose that ought to be fine, i.e. there is only one MessagePrinter for all threads, so if it is replaced in a multi-threaded manner it will cause other problems.

Definition at line 28 of file MessagePrinterOverlay.h.

Constructor & Destructor Documentation

◆ MessagePrinterOverlay() [1/2]

asg::MessagePrinterOverlay::MessagePrinterOverlay ( MessagePrinterOverlay & )

privatedelete

◆ MessagePrinterOverlay() [2/2]

asg::MessagePrinterOverlay::MessagePrinterOverlay ( IMessagePrinter * val_printer )

noexcept

overlay with the given message printer

Guarantee: no-fail

Precondition: val_printer != nullptr

Definition at line 25 of file MessagePrinterOverlay.cxx.

    : m_saved (getCurrent()), m_current (val_printer)
  {
    using namespace msgAsgMessaging;
 
    if (val_printer == nullptr)
    {
      ANA_MSG_FATAL ("nullptr passed illegally");
      std::abort ();
    }
    getCurrent() = val_printer;
  }

◆ ~MessagePrinterOverlay()

asg::MessagePrinterOverlay::~MessagePrinterOverlay ( )

noexcept

remove the currently overlaid printer

Guarantee: no-fail

Definition at line 41 of file MessagePrinterOverlay.cxx.

  {
    using namespace msgAsgMessaging;
 
    if (getCurrent() != m_current)
    {
      ANA_MSG_FATAL ("the overlay message printer changed underhand this should never happen");
      std::abort ();
    }
    getCurrent() = m_saved;
  }

Member Function Documentation

◆ current()

IMessagePrinter & asg::MessagePrinterOverlay::current ( )

staticnoexcept

get the current IMessagePrinter

Guarantee: no-fail

Definition at line 56 of file MessagePrinterOverlay.cxx.

  {
    return *getCurrent();
  }

◆ getCurrent()

IMessagePrinter *& asg::MessagePrinterOverlay::getCurrent ( )

staticprivatenoexcept

get a reference to the pointer to the current IMessagePrinter

Guarantee: no-fail

Postcondition: result != nullptr

Definition at line 64 of file MessagePrinterOverlay.cxx.

  {
    static MessagePrinter defaultPrinter;
    static IMessagePrinter *pointer = &defaultPrinter;
    return pointer;
  }

◆ operator=()

MessagePrinterOverlay asg::MessagePrinterOverlay::operator= ( MessagePrinterOverlay & )

privatedelete

Member Data Documentation

◆ m_current

IMessagePrinter* asg::MessagePrinterOverlay::m_current = nullptr

private

the current message printer we should have when we restore

Definition at line 77 of file MessagePrinterOverlay.h.

◆ m_saved

IMessagePrinter* asg::MessagePrinterOverlay::m_saved = nullptr

private

the stored message printer we need to restore

Definition at line 73 of file MessagePrinterOverlay.h.

The documentation for this class was generated from the following files:

Public Member Functions

Static Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes