Re: New branch name with no other changes

Quoting Hendrik Boom <[email protected]>:

> On Thu, Jun 09, 2011 at 02:14:16PM -0400, Hendrik Boom wrote,
>
> but forgot to mention he was using mtn 1.0:
>
>> I checked out a new workspace, and I want to check it in again unchenged
>> with a new branch name  -- the one I want to use to make changes.  I'd
>> like to make it clear that the new branch is starting in the same state
>> as the current head in the old one.

I use this:

function gds_create_mission(mission, from_branch, new_branch)
    local from_project, new_project, result, output, rev

    from_project = mission .. "." .. from_branch
    new_project = mission .. "." .. new_branch

    io.write("checking ...\n")
    result, output = mtn_automate("branches")
    if not result then
       error(string.format("Error from 'mtn_automate branches %s'", output))
    end

    if string.find (output, new_project) then
       error(string.format("%s branch already declared", new_project))
    end

    result, output = mtn_automate("heads", from_project)
    if not result then
       error(string.format("Error from 'mtn_automate heads %s'", from_project))
    end

    -- A single head gives an output with a single 40 byte rev id,  
plus newline.
    if #output > 41 then
       error(string.format("%s has multiple heads; need merge", from_project))
    end

    io.write(string.format("creating %s from %s\n", new_project, from_project))
    result, output = mtn_automate("select", "h:" .. from_project)
    if not result then
       error(string.format("Error from 'mtn_automate select %s'", "h:"  
.. from_project))
    end
    rev = string.sub(output, 1, 40)
    result, output = mtn_automate("cert", rev, "branch", new_project)
    if not result then
       error(string.format("Error from 'mtn_automate cert %s branch %s  
: %s'", rev, new_project, output))
    end
end

register_command("gds_create_mission", "mission from_branch  
new_branch", "create mtn branch for a GDS mission",
       "Create mtn branch derived from FROM_BRANCH, in MISSION.",
       "gds_create_mission")

The key command is "automate cert"; just add the new branch cert to  
the existing revision.

There have been discussions before about making something like this  
part of mtn, but nothing has been agreed on.


-- Stephe