What to include in a Dev Test Plan

Item Explanation
Description What is the feature intended for? How will it contribute to the overall business value?
Happy Paths The top user workflows of the feature that demonstrates the business values
Related Exisiting Feature Test Cases E.g. If we create a new chart type, we should test Export PDF for this new chart type
Changes to expected behaviour for exisiting features E.g. Key groups as a new feature which changed some expected behaviour of Share Plans / Analyses
Known limitations E.g. Can only do one Group-By. Or can only add primary metric as a filter
Known dependencies / risks How will the new code / code change get surfaced through the UI? Basically, full understanding of the code path and its riskes.
Migration required / New BP required / Impact on exisiting content Self-explaining. Good Example are Overlay and TCOW