Re: Mnemomic names for revisions
From: Brian Huddleston <brianh_at_huddleston.net>
Date: 2005-04-30 03:34:02 CEST
This would be a nice feature. Right now our QA department is in serious pain because while most/all of the tools allow you to diff rev 7 with rev 6. They usually don't allow you to diff rev 7 with tag/R9_3_2356.
Right now they have to poke around the log history in ViewCVS until they see what looks like the "tag"point then write down the revision number (that's a five digit number in our case as we imported our CVS repository) then go back and enter both numbers in.
While not impossible, it is a serious pain in the hoop. :-)
Well, the goal is to provide a (typically) mnemonic identifier for a particular snapshot of an SCC system. Since in SVN all revisions *are* snapshots, this equates to a mnemonic for a revision. To date, the only way to do this in SVN has been with tags, which provide the mnemonic through the name of a folder path in the repository.
I have two problems with this approach: (1) it clutters up the repository tree, which in big projects can be a mightmare, and (2) it's not clear except by convention that the "tag" should never be modified (otherwise its a branch, not a tag). I have trouble with #2 since it relies on out-of-band mechanisms (read: documentation+conventions) to indicate that it is a tag/label [sidebar: to my mind this is like saying we don't need "const" in a language since the same thing, more or less, can be done with comments.]
A "label" mechanism would elevate the tag concept to a first-class feature in SVN, making the intensions of the label in-band, and obviate the need for "tags" branches. Now, some aspects of such a feature are non-trivial: what exactly do you label? A directory? Does each label create a revision? If a label is a mnemonic for a revision, what does is mean to attempt to apply that label to some other part of a repository outside of the labeled directory?
Such issues would need to get resolved, but labels are indeed very useful outside of tags, IMHO.
Eric Hanchrow wrote:
I must be misunderstanding what revision labels are; to me they sound
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