CMT Tags
For what concerns the format of tags recognized by CMT, it appears that it is a lot more liberal that what one generally thinks. Actually, CMT only focus on the numbers in the tag names. It is up to the collaboration to choose one format or the other. The only advice is to avoid dots, if the CMT is used together with CVS, because CVS will not like dots in the tag names.
The format which is generally used in the CMT documentation can be expressed thanks to this perl expression : v[0-9]+(r[0-9]+(p[0-9]+)?)?. Yet, only the numbers are really meaningfull to CMT, and we do not know to what extent the tag v3p1 could be considered equivalent to v3r1, or even to MyPackage-v3p1. I suspect it is not fully consistent, as seen in some bugs, and it must be investigated.
Also, CMT tries to be independant of the versions management tool (CVS, SVN) and its concepts. In particular, CMT is not aware of CVS branches. Badly enough, CMT developers
uses the term "branches" for the subdirectories of a package.
CMT only cares for tags, and it get those tags for a package thanks to the command "cmt cvstags". The way the tags are ordered is unclear and linked to the implementation of the cmtcvs pluggin which is installed in the CVS repository. My current understanding is the following :
- For a given package, all the tags except the first one are given in the order they
appear in the cmt/requirements file in the repository ; it should be the same order as
the command "cvs rlog", and I guess it is chronological.
- The tag given first is expected to be the "latest" or more "recent" depending on
the source ; actually, it seems to be the tag which have greater numbers in the
corresponding CVS file release number.
CMT is not aware of the eventual collaboration policy for tags, so it is
considering all the tags, whatever they look like, and it does not care for
the CVS branches :
- If a branch has just been made for a given package, and no new tags have
been applied to the CVS trunk, then the last tag on the branch will be
displayed first by the "cmt cvstags" command.
- If the first tag returned by "cmt cvstags" must be filtered-out, then the
following tags are ordered chronologically, which means the branch ones
could come first if they have been made lately.
Release Manager LATEST
The Release Manager is filtering out all the tags which do not match v[0-9]+(r[0-9]+(p[0-9]+)?)?. This is a way not to take into account the tags which are applied on CVS branches, provided the developers do not use this format of tags on the branches !
LATEST is only applied to GlastRelease packages, not to EngineeringModel.
Release Manager HEAD
The tags which are used in a HEAD build are explicitly defined one by one, under the controll of Navid. There are HEAD version for every check out package : BeamtestRelease, EngineeringModel, GlastRelease and ScienceTools. By default, the same rules as LATEST applies for the name of tags, except for the preparation of patch versions.
For example if we prepare a v9r0p1 for GlastRelease, and some packages have received
modifications we do not want to incorporate
Branch Tags and Tags on Branchs
I suspect there is a confusion, at least in my head, between the tags which are defining a branch, and the tags which are applied to some revision which is on a branch. I will try to distinguish between the former, which I will call "branch tags", and the latter, which I will call "tags on branches".
In some place related to the Release Manager, it is said that the tags v*r*p* should not be used on branches, and that the Release Manager is filtering out whatever tag is not v*r*p*, so to avoid branch tags. It is unclear if we mean branch tags, or tags on branches, or both.
On the other hand, sometimes we prepare a GlastRelease v*r*p*, with the p* which means one of the constituent package is branched. And the release manager HEAD is expected to be a preparation for this new GlastRelease v*r*p*, and the release manager LATEST is expected to be a preparation for HEAD... so it is expected that some tags on branches will be used in LATEST, then in HEAD, then for GlastRelease v*r*p*.
Places where there is information about tags
About CVS branches.
About Release Manager.
Within CMT introduction, when clicking on "Tagging Conventions".