I ran into this myself. I tried to wrap with xerrors.Errorf("%w", err) and I was surprised when it didn't work. I debugged the wrong thing before changing it to ": %w".

I have a (clumsy, incomplete) fix for this at https://go-review.googlesource.com/c/xerrors/+/186957.

Would really like to see a fix for this too.

Current behavior is wrong - https://play.golang.org/p/QncO3iOhWji

Any news on this issue?

I updated my CL to fix the problem @sidh pointed out. I'm waiting for a review.

Another issue which actually has a TODO in the code - https://play.golang.org/p/KJZ0Uirj48r

(First, that CL was submitted, but for some reason this bug wasn't closed. I guess that's a blessing in disguise :)

@sidh, there are several such problems that would require better parsing of the format string. However, since Go 1.14 is coming out shortly and it will make xerrors obsolete, I don't think it's worth fixing them.

To clarify: once 1.14 is out, the only two officially supported versions of Go are 1.13 and 1.14, both of which have the new errors support. So if you follow the official policy, you can remove xerrors from your code.

Yeah, I've updated our version already.

Problem with switching to stdlib version of errors is you will miss out on stack frames and neat formatting. May be there is another package out there, all compatible with 1.13 errors? I'd prefer not to write it myself if there is one.

Fixed in CL 186957.