Detect and report changes in CSS between releases

[joshblack]

Between releases, we often will tweak or modify our Sass styles which in turn will cause downstream effects on libraries that consume and distribute the SCSS/CSS files for different libraries/frameworks/implementations.

Unfortunately, this means that many of the changes that we make to our stylesheet would be considered breaking changes for this audience. The lack of consistency or rate of change for certain selectors can be incredibly frustrating for these maintainers and can cause a number of downstream bugs due to lack of communication on our end for these changes.

As we go into our v11 release cycle, we would like to figure out a way to report on changes in CSS structure that can be reported between releases. Ideally, this would be in a changelog for teams that need this information to easily reference what updates they will need to make in order to adopt the latest version. Some of the changes that we would like to detect include:

• Selectors
  • Selector added
  • Selector removed
  • Selector renamed (most likely this is a combo of added/remove)