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How to document edge cases
Probably the The best place to document edge cases for new features would be a new section in the ticket description, the same way as we are doing i.e. it for acceptance criteria. Good edge case criteria should have described a scenario that differs from the main ones and expected behavior to handle that edge case.
When to identify edge cases
We strongly recommend identifying edge cases connected to the feature before working on the implementation. The person , who creates given the ticket or fills the description , should be the first to search for possible edge cases, as it is quite possible that he/she will have the proper knowledge to do so. Regardless of if the ticket has some edge cases defined or not yet , it should be reviewed on both Backlog Grooming meeting and most importantly on Sprint Planning meeting. Depending on the length of your Backlog Grooming meeting is a short one so there may be not enough time to review ticket carefully, so we suggest to at least to find and mark those tickets with a proper label, i.e. NeedsToIdentifyEdgeCases. Afterward, those tickets could be reviewed in depth on the Sprint Planning meeting by the dev team.
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