Thanks for reporting.

Can you please add a code example to demonstrate the issue you are referring to?

Not sure how to provide a code example to setup class with Date and beforeSave and post with invalid date. But anyone read my description should be able to reproduce on their server

How did you save an empty iso date?

This may be related to (or be a duplicate of) #7087, but without a proper code example we'll have to close this issue due to lack of details. The PR is also missing the test case and I wasn't able to infer anything from the PR itself.

I still have no time to learn the test system. So I spent half an hour to setup a project to demo the bug
https://github.com/sunshineo/parse-bug-demo
I hope the README.md is enough, but I can answer any questions

@sunshineo Thanks, this is actually the "code example" that was needed:

# Valid iso works in both classes
curl --location --request POST 'http://localhost:1337/parse/classes/MyClass1' \
--header 'x-parse-application-id: myAppId' \
--header 'x-parse-master-key: masterKey' \
--header 'Content-Type: application/json' \
--data-raw '{"field":{"__type":"Date", "iso":"2021-02-19T01:18:45.062Z"}}'

curl --location --request POST 'http://localhost:1337/parse/classes/MyClass2' \
--header 'x-parse-application-id: myAppId' \
--header 'x-parse-master-key: masterKey' \
--header 'Content-Type: application/json' \
--data-raw '{"field":{"__type":"Date", "iso":"2021-02-19T01:18:45.062Z"}}'


# Empty iso not working in MyClass1 with proper error
curl --location --request POST 'http://localhost:1337/parse/classes/MyClass1' \
--header 'x-parse-application-id: myAppId' \
--header 'x-parse-master-key: masterKey' \
--header 'Content-Type: application/json' \
--data-raw '{"field":{"__type":"Date", "iso": ""}}'

# Empty iso will stuck forever for MyClass2
curl --location --request POST 'http://localhost:1337/parse/classes/MyClass2' \
--header 'x-parse-application-id: myAppId' \
--header 'x-parse-master-key: masterKey' \
--header 'Content-Type: application/json' \
--data-raw '{"field":{"__type":"Date", "iso": ""}}'

It's still unclear to me why you are referring to two classes. What is the difference between class 1 and class 2? Wouldn't an empty or invalid iso date produce the same result in both classes?

No, MyClass2 has a beforeSave trigger, and that makes it stuck

I was able to reproduce the error throwing instead of promise rejection in #7217.

@sunshineo The code example to describe this issue is as simple as this, no need to create a repo or learn the test system:

Parse.Cloud.beforeSave('TestObject', () => {});

const obj = new Parse.Object('TestObject');
obj.set('date', { __type: 'Date', iso: '' });
await obj.save(); // Throws instead of rejects

Feel free to take a look at the test case added in #7217, you will see it is not much more than the code above. The test system we use is jasmine, it is descriptive, easy to learn and there are many existing tests in Parse Server that usually make for a good blueprint.

Now that we have a failing test case, would you want to investigate the root cause and provide a fix?

@mtrezza I have a fix. I have a pull request #7193
It's submitted before your test case. So is there a way to re-run the test and see if this fix make the test pass?

You could simply add the test to your PR.