The table of Delphi versions and their registry keys exists more than once
Brought to you by:
twm
Two scripts map each Delphi version to its registry key below HKLM\SOFTWARE and read RootDir from there, each with its own table:
packages/CheckPackages.ps1: $versions and Find-DelphiRootcompiletests/AllUnits/BuildForVersion.cmd: REG_VENDOR / REG_KEYbuildtools/delphiversions.cmd has a third table, version to default installation directory.
A new Delphi version, or a fix to the lookup, has to be made in each of them. One shared table, or one script that the others call, would avoid that.