Workarounds for Swift PM Bundle Handling

SwiftPMBundleHandling.m

// When working properly, SWIFTPM_MODULE_BUNDLE is defined. At least on Xcode 13.2, this is not always the case with
// packages, especially when running tests. The code below was pulled from my SF2Lib Swift package. This package is
// used in my SoundFonts application. The workaround below handles two situations where SWIFTPM_MODULE_BUNDLE is not
// working right:
//
// 1. SWIFTPM_MODULE_BUNDLE not defined -- seems to be limited to unit tests in the SF2Lib package
// 2. SWIFTPM_MODULE_BUNDLE defined but throws exception -- seems to be limited to unit tests of a package that depends
// on SF2Lib package
//

#if defined(SWIFTPM_MODULE_BUNDLE)

+ (NSString*)getConfigurationPath {
  
  // Here we are attempting to locate a "Configuration.plist" file in our bundle. This works properly when running on a
  // device or in a simulator. However when testing a component that depends on this Swift package, the Apple code that
  // sets SWIFTPM_MODULE_BUNDLE to the right NSBundle instance fails to locate the bundle and raises an exception. 
  // Here we catch it and provide a workaround.
  @try {
    return [SWIFTPM_MODULE_BUNDLE pathForResource:@"Configuration" ofType:@"plist"];
  } @catch (NSException *exception) {

    // Most likely we are in a unit test for something that depends on SF2Lib -- either the build system is not putting
    // stuff in the right location, or the code for SWIFTPM_MODULE_BUNDLE is not accounting for the test case.
    NSArray<NSBundle*>* allBundles = [NSBundle allBundles];
    for (int index = 0; index < [allBundles count]; ++index) {
      NSBundle* bundle = [allBundles objectAtIndex:index];
      NSString* bundleIdent = bundle.bundleIdentifier;
      NSLog(@"bundle: %@ - %@", bundleIdent, bundle.resourcePath);
      NSString* found = [bundle pathForResource:@"SF2Lib_SF2Lib" ofType:@"bundle"];
      if (found != NULL) {
        bundle = [[NSBundle alloc] initWithPath:found];
        bundleIdent = bundle.bundleIdentifier;
        NSLog(@"bundle: %@ - %@", bundleIdent, bundle.resourcePath);
        NSString* found = [bundle pathForResource:@"Configuration" ofType:@"plist"];
        if (found != NULL) return found;
      }
    }
    return NULL;
  }
}

#else

// Workaround for situations where SWIFTPM_MODULE_BUNDLE is not defined. This seems to be the case in all unit tests.
// We visit all known bundles and hope for the best.
+ (NSString*)getConfigurationPath {
  NSArray<NSBundle*>* allBundles = [NSBundle allBundles];
  for (int index = 0; index < [allBundles count]; ++index) {
    NSBundle* bundle = [allBundles objectAtIndex:index];
    NSString* bundleIdent = bundle.bundleIdentifier;
    NSLog(@"bundle: %@ - %@", bundleIdent, bundle.resourcePath);
    NSString* found = [bundle pathForResource:@"Configuration" ofType:@"plist"];
    if (found != NULL) return found;
  }

  return NULL;
}

#endif