react-native-health: Fatal Exception: NSInvalidArgumentException when retrieving health data

Thanks for creating this library.

Describe the bug After migrating an app from rn-apple-healthkit to react-native-health there have been a large number of crashes reported in Crashlytics. The crash seems to occur when health data is received. However I have been unable to reproduce this error myself on an iPhone simulator or a physical device.

This is the error: Fatal Exception: NSInvalidArgumentException ***[__NSPlaceholderDictionary initWithObjects:forKeys:count:]: attempt to insert nil object from objects[1]

Which seems to happen inside the completionHandler in the method fetchSumOfSamplesOnDayForType. This method is called from many other methods that retrieve various types of health data such as getStepCountOnDay.

Where one of these values in *response is nil, which due to the if-statement should be startDate or endDate. And buildISO8601StringFromDate can return nil if there is an error.

Inside the completionHandler:

if (!value && value != 0) {
            callback(@[RCTJSErrorFromNSError(error)]);
            return;
        }

         NSDictionary *response = @{
                 @"value" : @(value),
                 @"startDate" : [RCTAppleHealthKit buildISO8601StringFromDate:startDate],
                 @"endDate" : [RCTAppleHealthKit buildISO8601StringFromDate:endDate],
         };

        callback(@[[NSNull null], response]);

Do you have an idea what might cause this error?

These are the permissions that I use:

const appleHealthKitOptions = {
    permissions: {
        read: [
            AppleHealthKit.Constants.Permissions.StepCount,
            AppleHealthKit.Constants.Permissions.SleepAnalysis,
            AppleHealthKit.Constants.Permissions.HeartRate,
            AppleHealthKit.Constants.Permissions.DistanceCycling
        ],
        write: []
    }
};

And these AppleHealthKit methods:

AppleHealthKit.getDailyStepCountSamples
AppleHealthKit.getDailyDistanceCyclingSamples
AppleHealthKit.getSleepSamples
AppleHealthKit.getHeartRateSamples

To Reproduce Unfortunately I cannot reproduce it myself.

Smartphone (please complete the following information):

• Device: It happens on many different types of iPhones
• OS: Both iOS 13 and 14
• Version 1.7.0

Thanks a lot.