Target 2: diverging¶
Using a graphic convention, very common in git’s literature, we could represent the present situation in your repository with
A—B
That is: there are two commits , A and B. commit B is
A’s son (time moves to the right). The bolded commit identifies
the point where you are now.
What would happen if I made some changes and than committed?
It would happen that the new commit C thus generated will
be A’s son (because you’re starting from there), but the development
line would go on diverging from the A---B line.
That is, it would create this situation
A---B
\
C
Test:
echo "ei fu siccome immobile" > README.md
git add README.md
git commit -m "Here you have the C commit"
Show the result with
gitk --all
You got a branch, without the mechanism of file copy used by SVN at the moment of creation of a branch: git’s model based on key/value and pointers makes it very economic to represent a diverging development line.
Two important observations.
The first one is in order to reiterate the concept that git never stored deltas between
files: A, B and C are snapshots of the whole project. It’s
very important to remember this, because it’ll help you in understanding
that all observations you’ve always been in the habit to make with SVN,
might not apply with SVN.
The second might surprise you a little: the two diverging development lines you
have just seen are not branches. In git a branch is a pointer with a name,
or a label. I’m going to speak about this in the next paragraph, but get accustomed to
the idea that in git branches are not development branches.
