D27716: Fix accidental revealing of items when the game is restarted after lost from a middle click.

yuyichao created this revision.
yuyichao added reviewers: mlaurent, yurchor.
Herald added a reviewer: KDE Games.
Herald added a subscriber: kde-games-devel.
yuyichao requested review of this revision.

REVISION SUMMARY
  When a flag is misplaced, a middle click could cause the game to lost.
  Currently, if the user choose to restart the game in this case, there is a high chance
  that a few pieces around the one middle clicked are revealed right after the game restarted.
  
  The reason is that when the user restart the game in such case,
  it happens within `checkLost`/`onItemRevealed` which means that the
  game might not be the same one anymore after `onItemRevealed` returns
  and the loop handling all neighboring pieces are now operating on the now restarted game.
  
  The fix is to make sure the loop stops when the game is finished. Checking `m_gameOver` is
  unreliable and won't work in this case since the restart of the game would have restarted it.
  Instead, the finished status is returned from all functions that triggers such a condition
  and the information is propagated back to the caller to terminate the loop appropriately.
  This also improved another unreliable use of `m_gameOver` that is currently harmless.
  
  Debugging was possible thanks to `rr`.

REPOSITORY
  R404 KMines

BRANCH
  master

REVISION DETAIL
  https://phabricator.kde.org/D27716

AFFECTED FILES
  minefielditem.cpp
  minefielditem.h

To: yuyichao, mlaurent, yurchor, #kde_games
Cc: kde-games-devel