I've got a correct answer from official JetBrains support forum:
If you want to include information about build revisions in your notification you can try using something like this (see also SBuild.getRevisions method):
<#list build.revisions as revision> Revision: ${revision.repositoryVersion.displayVersion} VCS branch: ${revision.repositoryVersion.vcsBranch} </#list>
A couple of notes:
- there can be more than one VCS root in build, so number of revisions corresponds to number of VCS roots
- if changes are not yet collected for the build, or some error occurred while changes collecting, collection of revisions will be empty.
Pavel Sher