a main.m file for GHUnit that fixes problems described in gh-unit issue 96 - command line tests failing for Xcode 4.5 (and 4.6) for iOS 6

main.m

#import <objc/runtime.h>
#import <objc/message.h>

@interface UIWindow (Private)
- (void) swizzled_createContext;
@end

@implementation UIWindow (Private)
- (void) swizzled_createContext {
  // nop
}
@end


int main(int argc, char *argv[]) {
  int retVal;
  @autoreleasepool {
    CFMessagePortRef portRef = NULL;
    if (getenv("GHUNIT_CLI")) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wundeclared-selector"
      Method originalWindowCreateContext =
      class_getInstanceMethod([UIWindow class],
                              @selector(_createContext));
#pragma clang diagnostic pop
      
      Method swizzledWindowCreateConext =
      class_getInstanceMethod([UIWindow class],
                              @selector(swizzled_createContext));
      
       method_exchangeImplementations(originalWindowCreateContext,
                                      swizzledWindowCreateConext);
      
      
      portRef = CFMessagePortCreateLocal(NULL,
                                         (CFStringRef) @"PurpleWorkspacePort",
                                         NULL,
                                         NULL,
                                         NULL);
    }

    retVal = UIApplicationMain(argc, argv,
                               NSStringFromClass([UIApplication class]),
                               @"GHUnitIOSAppDelegate");
    if (portRef != NULL) { CFRelease(portRef); }
  }
  return retVal;
}

gh-unit issue: gh-unit/gh-unit#96

thanks @barumrho for pointing out that this
http://stackoverflow.com/questions/12557935/xcode-4-5-command-line-unit-testing/14395861#14395861
works.