internal/trace: recorder.Write returns 0 instead of n when buffer contains only header

[jjpinto]

Go version

1.25

Output of go env in your module/workspace:

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What did you do?

I was reviewing the code in src/internal/trace/recorder.go and noticed
that the Write method returns 0, nil when it successfully
processes a 16-byte header, even though it consumed all 16 bytes from the
input buffer.

What did you see happen?

In src/internal/trace/recorder.go, the Write method returns 0, nil
when the input buffer contains exactly 16 bytes (just the header), even
though it successfully consumed all 16 bytes.

What did you expect to see?

The method should return 16, nil to correctly implement the io.Writer
interface contract, which requires returning the number of bytes consumed.

[JunyangShao]

@golang/runtime

[mknyszek]

Thanks for the report. If you're up for sending a fix, feel free to do so (https://go.dev/doc/contribute), otherwise I'll get to it soon.

[jjpinto]

Thanks for the report. If you're up for sending a fix, feel free to do so (https://go.dev/doc/contribute), otherwise I'll get to it soon.

Sure, I will fix it.

[gopherbot]

Change https://go.dev/cl/734300 mentions this issue: internal/trace: fix recorder.Write return value for header-only buffers

[gabyhelp]

Related Code Changes

• internal/trace: fix recorder.Write return value for header-only buffers

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