No error when release:prepare with an already existing scm tag

This might be a svn server-side issue. I can confirm that this can go wrong at codehaus, but I've installed a complete system on a laptop and here the release stops if the tag already exists.

I'm confused about this ticket...does this bug report situation "A" or "B"?

A) there already exists a tag directory out on the remote svn_root of the name that I enter during the "mvn release:prepare" phase

or

B) there already exists an <scm><developerConnection>svn:///blah/blah/tags</developerConnection></scm> xml element in the pom of an artifact I'm about to release

I ran into the same issue where I forgot the remove the bad svn tag, release:perpare went thru without error, and therefor release:perform picks up the wrong source

The mvn release:rollback should at least remove the tag...

right, we have 2 options

a.) having release:prepare fail early if the tag already exists. And have release:rollback only WARN that the tag must get removed manually

b.) have release:rollback remove the tag as well if it exists and we have proper privileges. I'm always a bit reluctant fraidy-cat when doing a remove operation on an SCM ...

I think having release:prepare fail early if the tag already exists is a good idea in any case.

Well, you don't 'remove' anything from a scm. You just create a new version... So removing the tag when doing a release:rollback is a no brainer, IMO.

And, yes, a warning when doing a release:prepare if the tag already exists would definitively help !

> Well, you don't 'remove' anything from a scm. You just create a new version..

That depends on the SCM. This statement is only true for SVN. CVS ditched it sometimes even in it's attic (the first delete is fine, the 2nd destroyed the attic). And in GIT if you push a removal of a tag, then it's gone... Of course it's still in the downstream repos if they pulled it, but it's a history rewrite which is often not allowed. It is perfectly fine though if pushChanges=false for Hg and GIT! Needs a bit more brainwork I fear.

You're right. I had SVN in mind. It's a bit sad that some SCM consider that removing a tag == deleting it totally, but you'll have to deal with such a stupid decision. Hopefully, you have a clue about the used SCM, so the plugin can behave accordingly.
Note that it will requires way more work

I'm not worried about the additional work needed. But I'm really worried that we pack all this information in our maven-release-manager. There is already way too much hardcoded stuff which is specific for single SCMs in there. I'd rather move all this information into the scm-api instead.