[CMake] Checkout specific revision from svn with ExternalProject_Add

[Jens Auer]

Hi,

I am trying to checkout a specific revision of external dependencies from our repositoty using the SVN_REPOSITOTY parameter of ExternalProject_Add, but always get the following error:
2>  Creating directories for 'Hippomocks'
2>  Performing download step (SVN checkout) for 'Hippomocks'
2>  A    Hippomocks\hippomocks\include
2>  A    Hippomocks\hippomocks\include\hippomocks
2>  A    Hippomocks\hippomocks\include\hippomocks\hippomocks.h
2>  A    Hippomocks\hippomocks\CMakeLists.txt
2>  Checked out revision 8888.
2>  svn: E125002: '8887' does not appear to be a URL

When I looked into the source code, I see that the command line for svn is created as
    set(cmd ${Subversion_SVN_EXECUTABLE} co ${svn_repository} ${svn_revision}
      --non-interactive ${svn_trust_cert_args} ${svn_user_pw_args} ${src_name})

According to the svn documentation page, I would have to give the revision with a special option -revision. Is this a bug or am I misinterpreting the ExternalProject_Add command parameters? Is SVN_REVISION the path in the repository I specify with SVN_REPOSITORY?