A primer on remote branches with Git

Here we assume that

You have set up a local working directory to edit the source code of Simutrans-Experimental, your favorite game; and
Tou would like to compile one of the branches to test it.

First, setup git. Now we go get James's repository:

$ git clone https://github.com/jamespetts/simutrans-experimental

List remote branches only:

$ git branch -r

List all remote branches, and lots of other info:

$ git remote show origin

Create a local branch to track a remote branch:

$ git branch --track running-powers origin/running-powers

Have our local working copy, track the named branch:

$ git checkout running-powers

Go get it

$ git pull

Show local branches:

$ git branch
10.x
master
* running-powers

OK let's build that:

$ make -j3
[...]
===> LD build/default/simutrans-experimental

Cool! Now, copy that binary to our games-playing directory:

$ cp -a build/default/simutrans-experimental ~/simutrans/sim-exp/

If some git commands refuse to proceed because they’re worried about clobbering untracked files, and you’re certain that all untracked files and directories are expendable, then delete them mercilessly with:

$ git clean -f -d

Git: Untracked files problem

Tags: clean delete git merge untracked files

I edited my working copy of a project in git and now I can't do a git pull to merge, because I added a few files. I don't have commit privileges on the remote project, so I emailed them to the maintainer, and now git won't merge them in. I get this error:

error: The following untracked working tree files would be overwritten by merge:

There are two ways to handle this:

git add . Adds the names of the files in the local copy, to git's concept of tracked files. Then a git fetch will succeed.
git clean -n will do a dry run (-n) of a clean operation, which will remove all non-tracked files from your local copy. If you agree, git clean -d will actually delete thosee files; then git fetch or git pull will succeed.

What will happen if I 'git fetch' or 'git pull'?

Tags: diff remote fetch git preview changes pull remote diff what changed

If you have used svn for years, git can seem a little strange.

Half the problem is the different mindset -- let's tackle one common problem: How do I know what will happen if I do a git fetch or a git pull? First let's do a status:

$ git status
# On branch master
# Your branch is behind 'origin/master' by 3 commits,
  and can be fast-forwarded.

That's a lot friendlier than svn's equivalent svn diff. And that status gives us the clue as to what we would like to compare: it's simply our copy (master) and the one it's "behind" (origin/master). So if we request:

$ git diff master origin/master

we will get a nice difference between our copy (shown in the diff with -) and the remote (shown with +).