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Second, please include tests with your patch. If your patch does not include tests, it will not be accepted. If you are unsure how to write tests for a particular component, please ask on the impala-dev mailing list for guidance.
Third, run all the existing Impala test to ensure your fix doesn't introduce any new issues. See for more details.
Fourth, please keep your patch narrowly targeted to the problem described by the JIRA. It’s better for everyone if we maintain discipline about the scope of each patch. In general, if you find a bug while working on a specific feature, file a JIRA for the bug, check if you can assign it to yourself and fix it independently of the feature. This helps us to differentiate between bug fixes and features and allows us to build stable maintenance releases.
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