Understanding a Subtle Bug in Go's errgroup and the Importance of Testing
By
broken_broken_
If you only eat one bagel today, this is the bagel.
Summary
The article discusses a subtle bug encountered while working with Go's errgroup in a project called Kratos. The author shares their experience of how a test caught the bug before it could be merged into production, emphasizing the importance of testing in complex software development. A minimized version of the issue is provided in a 100-line standalone program, and the real production code is linked for reference.
Key quotes
· 4 pulledYesterday I got bitten by an insidious bug at work while working on Kratos.
The more I work on big, complex software, the more I deeply appreciate tests, even though I do not necessarily enjoy writing them.
I lost a few hours investigating this issue, and this could happen to anyone, I think.
You can have a look at the real production code here if you are interested. After all, it's open source!
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