Re: "git merge" merges too much!

[Dmitry Potapov <dpotapov@gmail.com>]

On Mon, Nov 30, 2009 at 01:40:38PM -0500, Greg A. Woods wrote:
> 
> While it may be quite convenient in small projects to quickly move a
> single working directory from one branch to another and do various
> builds and tests from the result, large projects (say where a compile
> takes the better part of a working day or more and where testing
> requires multi-day processes) demand that working directories remain
> "stable", and multiple lines of development therefore demand multiple
> working directories.

It depends on the project and what tools are used, but using ccache and
proper dependencies help a lot to reduce the cost of switching. In fact,
it may be faster to switch to another branch and have to recompile a few
files than to go into another working directory, because when you go to
another working directory, you hit cold cache and things get very slow.

And then if a project is huge and takes a lot of time to compile and
test everything, I do not think, it is a good idea to build that in your
work tree. Instead, you make a shanshot using git-archive and then run
full build and test on it. In this way, you know that you test exactly
what you have committed (you can amend any commit later until you
publish it).


Dmitry