NAME

       dpkg-mergechangelogs - 3-way merge of debian/changelog files

SYNOPSIS

       dpkg-mergechangelogs [option...] old new-a new-b [out]

DESCRIPTION

       This program will use the 3 provided versions of the Debian changelog to generate a merged
       changelog file. The resulting changelog is stored  in  the  file  out  or  output  to  the
       standard output if that parameter is not given.

       Each entry is identified by its version number and they are assumed to be not conflicting,
       they  are  simply  merged  in  the  right  order  (by  decreasing  version  number).  When
       --merge-prereleases  is  used,  the  part  of  the  version number after the last tilde is
       dropped so that 1.0-1~exp1 and 1.0-1~exp5 are considered to be the same  entry.  When  the
       same  version  is  available in both new-a and new-b, a standard line-based 3-way merge is
       attempted (provided that the module Algorithm::Merge is  available  —  it's  part  of  the
       package  libalgorithm-merge-perl  —  otherwise you get a global conflict on the content of
       the entry).

OPTIONS

       -m, --merge-prereleases
              Drop the part after the last  tilde  in  the  version  number  when  doing  version
              comparison to identify if two entries are supposed to be the same or not.

              This  is  useful  when you keep using the same changelog entry but you increase its
              version number regularly. For instance, you might have 2.3-1~exp1, 2.3-1~exp2,  ...
              until the official release 2.3-1 and they are all the same changelog entry that has
              evolved over time.

       --help Show the usage message and exit.

       --version
              Show the version and exit.

LIMITATIONS

       Anything that is not parsed by Dpkg::Changelog is  lost  during  the  merge.   This  might
       include  stuff like Vim modelines, Emacs variables, comments which were not supposed to be
       there, etc.

INTEGRATION WITH GIT

       If you want to use this program to merge Debian changelog files in a git  repository,  you
       have first to register a new merge driver in .git/config or ~/.gitconfig:

        [merge "dpkg-mergechangelogs"]
            name = debian/changelog merge driver
            driver = dpkg-mergechangelogs -m %O %A %B %A

       Then  you  have  to  setup  the  merge  attribute  for the debian/changelog file either in
       .gitattributes in the repository itself, or in .git/info/attributes:

        debian/changelog merge=dpkg-mergechangelogs