@Dependency(\.date.now) is returning incorrect dates (either in future or past) when used in escaping closures

[desusai-doordash]

Description

I am not able to reproduce this, but observed in production that the dates retrieved using @Dependency(\.date.now) are incorrect in many cases. Some times they are from future and sometimes they are from past.

After going through the documentation, i've noticed that it's stated here that we should use withEscapedDependencies to reflect correct values in case of passing over dependencies to escaping closures. Would this apply for the dependencies provided by default like Date as well ?

Would using withEscapedDependencies solve the issue with incorrect dates ?

Here is a sample code to demonstrate how I am using the value of date from @Dependency(\.date.now) in an escaping closure, if that would be helpful to understand more about the issue.

@Dependency(\.date.now) private var now
private var startTime: Date?
private let scheduler: AnySchedulerOf<DispatchQueue>

.....

scheduler.schedule { [weak self, now] in
            self?.startTime = now
 }

In the above codebase I am seeing startTime is getting assigned with date either from future or past.

Checklist

• I have determined whether this bug is also reproducible in a vanilla SwiftUI project.
• If possible, I've reproduced the issue using the main branch of this package.
• This issue hasn't been addressed in an existing GitHub issue or discussion.

Expected behavior

Correct date value should be available inside the closure.

Actual behavior

Incorrect date values are available within the closure.

Steps to reproduce

I am not able to reproduce this, may be this is happening at a high level of concurrency.

Dependencies version information

1.6.1

Destination operating system

Across iOS versions

Xcode version information

No response

Swift Compiler version information

[desusai-doordash]

@stephencelis, Can you please help me with above question ?

[pyrtsa]

If you capture @Dependency(\.date.now) var now in a closure such as { [now] in ... }, then you'll actually freeze the Date value as of the original construction of the closure, not the computed property. You should instead look into using withEscapedDependencies(_:).

[desusai-doordash]

@pyrtsa yes, I want to freeze the Date value during the construction of the closure and use it within the closure, hence I am capturing it, but what I've noticed is that the value of date within the closure is sometimes into the future or past but not the date during the construction of colsure. It could either be a day/week/month into the future or past.

[desusai-doordash]

I took a deep dive into the code and found that Date.now is a computed property with a getter that returns a new Date() value each time it's accessed. So, the swift-dependencies package shouldn't really affect or manipulate the value once it's captured in the closure, because it's evaluated at the moment it's captured.

Does anyone have any insights on what might cause the date to be manipulated later?

[mbrandonw]

Hi @desusai-doordash, please do not tag us directly in issues/discussions.

You will need to share more information in order for anyone to help. Can you reproduce the problem you are seeing in a fresh, minimal project and share that?

Since it isn't clear this is an issue with the library I am going to convert it to a discussion. Please feel free to continue the conversation over there!