Loki/test/ScopeGuard/main.cpp
rich_sposato 3706b5d249 Added test for exception handling policies.
git-svn-id: svn://svn.code.sf.net/p/loki-lib/code/trunk@1083 7ec92016-0320-0410-acc4-a06ded1c099a
2011-06-21 01:11:50 +00:00

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////////////////////////////////////////////////////////////////////////////////
// The Loki Library
// Copyright (c) 2006 Peter K<>mmel
// Permission to use, copy, modify, distribute and sell this software for any
// purpose is hereby granted without fee, provided that the above copyright
// notice appear in all copies and that both that copyright notice and this
// permission notice appear in supporting documentation.
// The author makes no representations about the
// suitability of this software for any purpose. It is provided "as is"
// without express or implied warranty.
////////////////////////////////////////////////////////////////////////////////
// $Id$
#include <loki/ScopeGuard.h>
#include <vector>
#include <string>
#include <iostream>
#include <assert.h>
using namespace Loki;
// ----------------------------------------------------------------------------
void HasNone( void )
{
}
void HasOne( int p1 )
{
(void)p1;
}
void HasTwo( int p1, int p2 )
{
(void)p1;
(void)p2;
}
void HasThree( int p1, int p2, int p3 )
{
(void)p1;
(void)p2;
(void)p3;
}
void HasFour( int p1, int p2, int p3, int p4 )
{
(void)p1;
(void)p2;
(void)p3;
(void)p4;
}
void HasFive( int p1, int p2, int p3, int p4, int p5 )
{
(void)p1;
(void)p2;
(void)p3;
(void)p4;
(void)p5;
}
void Decrement( unsigned int & x )
{
--x;
}
struct UserDatabase
{
void AddFriend(const std::string&, const std::string&)
{
throw 55;
}
};
class User
{
public:
User(UserDatabase* db) : fCount(0), pDB_(db)
{}
std::string GetName() const;
void AddFriend(User& newFriend);
void AddFriendGuarded(User& newFriend);
void AddFriendGuardedMacros(User& newFriend);
size_t countFriends() const;
void DoSomething() const;
unsigned int fCount;
void HasNone( void ) const;
void HasOne( int p1 ) const;
void HasTwo( int p1, int p2 ) const;
void HasThree( int p1, int p2, int p3 ) const;
void HasFour( int p1, int p2, int p3, int p4 ) const;
void HasFive( int p1, int p2, int p3, int p4, int p5 ) const;
private:
void CheckIfValid( const char * function, unsigned int line ) const;
typedef std::vector<User*> UserCont;
UserCont friends_;
UserDatabase* pDB_;
};
void User::HasNone( void ) const
{
}
void User::HasOne( int p1 ) const
{
(void)p1;
}
void User::HasTwo( int p1, int p2 ) const
{
(void)p1;
(void)p2;
}
void User::HasThree( int p1, int p2, int p3 ) const
{
(void)p1;
(void)p2;
(void)p3;
}
void User::HasFour( int p1, int p2, int p3, int p4 ) const
{
(void)p1;
(void)p2;
(void)p3;
(void)p4;
}
void User::HasFive( int p1, int p2, int p3, int p4, int p5 ) const
{
(void)p1;
(void)p2;
(void)p3;
(void)p4;
(void)p5;
}
void User::DoSomething() const
{
}
void User::CheckIfValid( const char * function, unsigned int line ) const
{
assert( friends_.size() == fCount );
(void)function;
(void)line;
}
std::string User::GetName() const
{
return "A name";
}
size_t User::countFriends() const
{
return friends_.size();
}
void User::AddFriend(User& newFriend)
{
ScopeGuard invariantGuard = MakeObjGuard( *this,
&User::CheckIfValid, __FUNCTION__, __LINE__ );
(void)invariantGuard;
friends_.push_back(&newFriend);
fCount++;
pDB_->AddFriend(GetName(), newFriend.GetName());
}
void User::AddFriendGuarded(User& newFriend)
{
ScopeGuard invariantGuard = MakeObjGuard( *this,
&User::CheckIfValid, __FUNCTION__, __LINE__ );
(void)invariantGuard;
ScopeGuard guard1 = MakeObjGuard( *this, &User::DoSomething );
(void)guard1;
friends_.push_back(&newFriend);
Loki::ScopeGuard guard = Loki::MakeObjGuard(friends_, &UserCont::pop_back);
fCount++;
Loki::ScopeGuard guardRef = Loki::MakeGuard(Decrement, Loki::ByRef(fCount));
pDB_->AddFriend(GetName(), newFriend.GetName());
guard.Dismiss();
guardRef.Dismiss();
}
void User::AddFriendGuardedMacros(User&)
{
ScopeGuard invariantGuard = MakeObjGuard( *this,
&User::CheckIfValid, __FUNCTION__, __LINE__ );
(void)invariantGuard;
LOKI_ON_BLOCK_EXIT_OBJ(friends_, &UserCont::pop_back); (void) LOKI_ANONYMOUS_VARIABLE(scopeGuard);
// GCC 4.2 Bug
#if defined(__GNUC__)
#define GCC_VERSION (__GNUC__ * 10 + __GNUC_MINOR__ * 1)
#endif
#if !defined(__GNUC__) || (GCC_VERSION < 42) || (GCC_VERSION > 42)
LOKI_ON_BLOCK_EXIT(Decrement, Loki::ByRef(fCount)); (void) LOKI_ANONYMOUS_VARIABLE(scopeGuard);
#endif
}
void DoStandaloneFunctionTests()
{
ScopeGuard guard0 = MakeGuard( &HasNone );
ScopeGuard guard1 = MakeGuard( &HasOne, 1 );
ScopeGuard guard2 = MakeGuard( &HasTwo, 1, 2 );
ScopeGuard guard3 = MakeGuard( &HasThree, 1, 2, 3 );
ScopeGuard guard4 = MakeGuard( &HasFour, 1, 2, 3, 4 );
ScopeGuard guard5 = MakeGuard( &HasFive, 1, 2, 3, 4, 5 );
(void)guard0;
(void)guard1;
(void)guard2;
(void)guard3;
(void)guard4;
(void)guard5;
}
void DoMemberFunctionTests( User & user )
{
ScopeGuard guard0 = MakeObjGuard( user, &User::HasNone );
ScopeGuard guard1 = MakeObjGuard( user, &User::HasOne, 1 );
ScopeGuard guard2 = MakeObjGuard( user, &User::HasTwo, 1, 2 );
ScopeGuard guard3 = MakeObjGuard( user, &User::HasThree, 1, 2, 3 );
(void)guard0;
(void)guard1;
(void)guard2;
(void)guard3;
}
// ----------------------------------------------------------------------------
void CalledAlways( void )
{
const bool anyThrown = ::std::uncaught_exception();
const char * message = ( anyThrown ) ? "thrown" : "not thrown";
::std::cout << __FUNCTION__ << " Exception was " << message << ::std::endl;
}
// ----------------------------------------------------------------------------
void CalledIfNoException( void )
{
const bool anyThrown = ::std::uncaught_exception();
const char * message = ( anyThrown ) ? "thrown" : "not thrown";
::std::cout << __FUNCTION__ << " Exception was " << message << ::std::endl;
}
// ----------------------------------------------------------------------------
void CalledIfException( void )
{
const bool anyThrown = ::std::uncaught_exception();
const char * message = ( anyThrown ) ? "thrown" : "not thrown";
::std::cout << __FUNCTION__ << " Exception was " << message << ::std::endl;
}
// ----------------------------------------------------------------------------
void FunctionMightThrow( bool willThrow )
{
if ( willThrow )
throw ::std::exception();
}
// ----------------------------------------------------------------------------
void DoExceptionTests( void )
{
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledAlways );
(void)guard;
FunctionMightThrow( false );
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
assert( false );
}
}
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledAlways );
(void)guard;
FunctionMightThrow( true );
assert( false );
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
}
}
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledIfNoException );
guard.SetExceptionPolicy( ScopeGuardImplBase::CallIfNoException );
FunctionMightThrow( false );
::std::cout << "No exception thrown." << ::std::endl;
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
assert( false );
}
}
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should not be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledIfNoException );
guard.SetExceptionPolicy( ScopeGuardImplBase::CallIfNoException );
FunctionMightThrow( true );
assert( false );
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
}
}
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should not be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledIfException );
guard.SetExceptionPolicy( ScopeGuardImplBase::CallIfException );
FunctionMightThrow( false );
::std::cout << "No exception thrown." << ::std::endl;
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
assert( false );
}
}
::std::cout << ::std::endl;
{
try
{
::std::cout << "The function should be called." << ::std::endl;
ScopeGuard guard = MakeGuard( &CalledIfException );
guard.SetExceptionPolicy( ScopeGuardImplBase::CallIfException );
FunctionMightThrow( true );
assert( false );
}
catch ( ... )
{
::std::cout << "Caught exception." << ::std::endl;
}
}
::std::cout << ::std::endl;
}
// ----------------------------------------------------------------------------
class Junk
{
public:
Junk( void );
~Junk( void );
bool IsUgly( void ) const;
bool IsUseful( void ) const;
};
// ----------------------------------------------------------------------------
Junk::Junk( void )
{
assert( NULL != this );
}
// ----------------------------------------------------------------------------
Junk::~Junk( void )
{
assert( NULL != this );
}
// ----------------------------------------------------------------------------
bool Junk::IsUgly( void ) const
{
assert( NULL != this );
return true;
}
// ----------------------------------------------------------------------------
bool Junk::IsUseful( void ) const
{
assert( NULL != this );
return true;
}
// ----------------------------------------------------------------------------
class Attic
{
public:
Attic( void );
~Attic( void );
Junk * RemoveUselessJunk( void );
private:
typedef ::std::vector< Junk * > JunkPile;
typedef JunkPile::iterator JunkPileIter;
void CheckInvariants( const char * function, unsigned int line ) const;
void CallObservers( void ) const;
void EliminateHoles( void );
JunkPile m_storage;
};
// ----------------------------------------------------------------------------
Attic::Attic( void ) :
m_storage()
{
}
// ----------------------------------------------------------------------------
Attic::~Attic( void )
{
}
// ----------------------------------------------------------------------------
Junk * Attic::RemoveUselessJunk( void )
{
ScopeGuard callGuard = MakeObjGuard( *this, &Attic::CallObservers );
ScopeGuard testGuard = MakeObjGuard( *this, &Attic::CheckInvariants, __FUNCTION__, __LINE__ );
ScopeGuard fixGuard = MakeObjGuard( *this, &Attic::EliminateHoles );
callGuard.SetExceptionPolicy( ScopeGuardImplBase::CallIfNoException );
(void)testGuard;
(void)fixGuard;
for ( JunkPileIter it( m_storage.begin() );
it != m_storage.end();
++it )
{
Junk * junk = *it;
if ( junk->IsUgly() )
return junk;
if ( junk->IsUseful() )
continue;
delete junk;
*it = NULL;
}
return NULL;
}
// ----------------------------------------------------------------------------
void Attic::CheckInvariants( const char * function, unsigned int line ) const
{
assert( NULL != this );
(void)function;
(void)line;
}
// ----------------------------------------------------------------------------
void Attic::CallObservers( void ) const
{
}
// ----------------------------------------------------------------------------
void Attic::EliminateHoles( void )
{
}
// ----------------------------------------------------------------------------
int main()
{
UserDatabase db;
User u1(&db);
User u2(&db);
try{ u1.AddFriend(u2); }
catch (...){}
std::cout << "u1 countFriends: " << u1.countFriends() << "\n";
std::cout << "u1 fCount : " << u1.fCount << "\n";
try{ u2.AddFriendGuarded(u1); }
catch (...){}
std::cout << "u2 countFriends: " << u2.countFriends() << "\n";
std::cout << "u2 fCount : " << u2.fCount << "\n";
DoStandaloneFunctionTests();
DoMemberFunctionTests( u1 );
DoExceptionTests();
#if defined(__BORLANDC__) || defined(_MSC_VER)
system("PAUSE");
#endif
}