In our manual we have a guideline to add a -git suffix to the name. This contradicts my usual experience and also can be (rightfully) interpreted very broadly, e.g. in #14571. My views on this are:

1. We don't usually use this suffix -- grep shows 42 usages of this, and from my own (not backed by numbers because it's difficult to construct good regexp for this) experience non-suffixed packages occur much more often.
2. Why only -git? We should suffix all version control systems like this if we decide to uphold this practice.
3. From my point of view it's an upstream implementation detail -- if we have a date instead of version it indicates that it's some code snapshot already.

We should also clarify if we want only package name to be suffixed, or attribute name and package directory should be suffixed too (as seen in #14571).

(Usage counted by grep -r -- '-git-2' and grep -r -- '-git-\$')