mod=example.com/basic/v2
version=v2.1.0
base=v2.0.1
release=v2.1.0
proxyVersions=example.com/basic/v2@v2.0.1
-- want --
example.com/basic/v2/a
----------------------
Compatible changes:
- A2: added

example.com/basic/v2/b
----------------------
Compatible changes:
- package added

v2.1.0 is a valid semantic version for this release.