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0 pointskromem2y ago0 comments

Great, so Go has support for native stacktraces so bubbled errors don't get shadowed?

Just because Go made opinionated design decisions around their error handling a decade ago when developing the language doesn't mean that there's not practical room for improvement as the language is widely in production and shortcomings in its error handling have been found.

The number of hacks I've seen over the years to try and solve the "wait, where did this error originate" problem in Go are legion, with little standardization.

And no, using Errorf with '%w' to wrap error messages along the stack isn't exactly an elegant solution.

Even if they want to keep the core error behavior as it is for compatibility, providing a core library way of wrapping with stacktraces would be a very useful next step, particularly given the most popular package doing that previously is now unmaintained.

0 comments

randomdata2y ago

> providing a core library way of wrapping with stacktraces would be a very useful next step

What eventually became the standard library error wrapping proposal evolved from the work done on the Upspin project. It did include stacktraces, and believed like you that it would be useful to have them. But analysis of the data showed that nobody ever really used them in practice and, for that reason, was removed from the final proposal.

> particularly given the most popular package doing that previously is now unmaintained.

Lacking wide appeal doesn't mean there isn't a niche need, of course. However, with the standard library accepting a standard for error wrapping, which this package you speak of has been updated to be compatible with, what further maintenance would be needed, exactly? It would be more concerning if it wasn't considered finished by now. It seems the solution for niche needs is right there.

physicles2y ago

In the last few months I've realized what I desperately need: a way to wrap an error with a call stack at the point where it enters our code base. This would probably save me on average 20-30 minutes a week.

I see this all the time:

   main.go:141 error: could not transmogrify the thing: a144cd21c48

And then I literally grep the code base to find the error message. That works ~50% of the time, but the other 50%, I see this:

   main.go:141 error: not found

And then I have to spend 5-10 minutes spelunking to try to find where that error might have originated from.

But this would be amazing:

   main.go:141 error: not found callstack=...

tombh2y ago

This is such an infuriating problem. I'm convinced I'm using Go wrong, because I simply can't understand how this doesn't make it a toy language. Why the $expletive am I wasting 20-30 and more minutes per week of my life looking for the source of an error!?

Have you seen https://github.com/tomarrell/wrapcheck? It's a linter than does a fairly good job of warning when an error originates from an external package but hasn't been wrapped in your codebase to make it unique or stacktraced. It comes with https://github.com/golangci/golangci-lint and can even be made part of your in-editor LSP diagnostics.

But still, it's not perfect. And so I remain convinced that I'm misunderstanding something fundamental about the language because not being able to consistently find the source of an error is such an egregious failing for a programming language.

1 more reply

randomdata2y ago

Its flaws or merits aside, when you have no other useful context to add to the error, that's precisely what Errorf is for.

  func bar() error {
    err := baz.Transmogrify()
    return fmt.Errorf("transmogrify: %w", err)
  }

  func foo() error {
    err := bar()
    return fmt.Errorf("bar: %w", err)
  }

  func main() {
    err := foo()
    fmt.Printf("foo: %v", err)
    // foo: bar: transmogrify: not found
  }

There's your callstack, without the cost of carrying around the actual callstack.

3 more replies

kitd2y ago

Agreed. In fact I wrote a (very) small library to help deal with it.

https://github.com/kitd/chock

philosopher12342y ago

>And no, using Errorf with '%w' to wrap error messages along the stack isn't exactly an elegant solution.

I don't think anyone has ever claimed otherwise. But I do think its a pretty good solution. Whats elegance worth, anyways?

j / k navigate · click thread line to collapse

0 comments

randomdata2y ago

> providing a core library way of wrapping with stacktraces would be a very useful next step

> particularly given the most popular package doing that previously is now unmaintained.

physicles2y ago

I see this all the time:

   main.go:141 error: could not transmogrify the thing: a144cd21c48

And then I literally grep the code base to find the error message. That works ~50% of the time, but the other 50%, I see this:

   main.go:141 error: not found

And then I have to spend 5-10 minutes spelunking to try to find where that error might have originated from.

But this would be amazing:

   main.go:141 error: not found callstack=...

tombh2y ago

1 more reply

randomdata2y ago

Its flaws or merits aside, when you have no other useful context to add to the error, that's precisely what Errorf is for.

  func bar() error {
    err := baz.Transmogrify()
    return fmt.Errorf("transmogrify: %w", err)
  }

  func foo() error {
    err := bar()
    return fmt.Errorf("bar: %w", err)
  }

  func main() {
    err := foo()
    fmt.Printf("foo: %v", err)
    // foo: bar: transmogrify: not found
  }

There's your callstack, without the cost of carrying around the actual callstack.

3 more replies

kitd2y ago

Agreed. In fact I wrote a (very) small library to help deal with it.

https://github.com/kitd/chock

philosopher12342y ago

>And no, using Errorf with '%w' to wrap error messages along the stack isn't exactly an elegant solution.

I don't think anyone has ever claimed otherwise. But I do think its a pretty good solution. Whats elegance worth, anyways?

j / k navigate · click thread line to collapse