Git log to get commits only for a specific branch

I want to list all commits that are only part of a specific branch.

With the following, it lists all the commits from the branch, but also from the parent (master)

git log mybranch

The other option I found, was to exclude the commits reachable by master and gives me what I want, BUT I would like to avoid the need of knowing the other branches names.

git log mybranch --not master

I was trying to use git for-each-ref, but it is also listing mybranch so actually it is excluding all:

git log mybranch --not $(git for-each-ref --format '^%(refname:short)' refs/heads/)

Update:

I'm testing a new option that I found a while ago, and till now seems that this could be what I was looking for:

git log --walk-reflogs mybranch

Update (2013-02-13T15:08):

The --walk-reflogs option is good, but I checked that there is an expiration for reflogs (default 90 days, gc.reflogExpire).

I think I found the answer I was looking for:

git log mybranch --not $(git for-each-ref --format='%(refname)' refs/heads/ | grep -v "refs/heads/mybranch")

I'm just removing the current branch from list of branches available and using that list to be excluded from the log. This way I only get the commits that are only reached by mybranch.

Solution 1:

From what it sounds like you should be using cherry:

git cherry -v develop mybranch

This would show all of the commits which are contained within mybranch, but NOT in develop. If you leave off the last option (mybranch), it will compare the current branch instead.

As VonC pointed out, you are ALWAYS comparing your branch to another branch, so know your branches and then choose which one to compare to.

Solution 2:

BUT I would like to avoid the need of knowing the other branches names.

I don't think this is possible: a branch in Git is always based on another one or at least on another commit, as explained in "git diff doesn't show enough":

enter image description here

You need a reference point for your log to show the right commits.

As mentioned in "GIT - Where did I branch from?":

branches are simply pointers to certain commits in a DAG

So even if git log master..mybranch is one answer, it would still show too many commits, if mybranch is based on myotherbranch, itself based on master.

In order to find that reference (the origin of your branch), you can only parse commits and see in which branch they are, as seen in:

"Git: Finding what branch a commit came from".
"How can I see what branch another branch was forked from?"

Solution 3:

I finally found the way to do what the OP wanted. It's as simple as:

git log --graph [branchname]

The command will display all commits that are reachable from the provided branch in the format of graph. But, you can easily filter all commits on that branch by looking at the commits graph whose * is the first character in the commit line.

For example, let's look at the excerpt of git log --graph master on cakephp GitHub repo below:

D:\Web Folder\cakephp>git log --graph master
*   commit 8314c2ff833280bbc7102cb6d4fcf62240cd3ac4
|\  Merge: c3f45e8 0459a35
| | Author: José Lorenzo Rodríguez <[email protected]>
| | Date:   Tue Aug 30 08:01:59 2016 +0200
| |
| |     Merge pull request #9367 from cakephp/fewer-allocations
| |
| |     Do fewer allocations for simple default values.
| |
| * commit 0459a35689fec80bd8dca41e31d244a126d9e15e
| | Author: Mark Story <[email protected]>
| | Date:   Mon Aug 29 22:21:16 2016 -0400
| |
| |     The action should only be defaulted when there are no patterns
| |
| |     Only default the action name when there is no default & no pattern
| |     defined.
| |
| * commit 80c123b9dbd1c1b3301ec1270adc6c07824aeb5c
| | Author: Mark Story <[email protected]>
| | Date:   Sun Aug 28 22:35:20 2016 -0400
| |
| |     Do fewer allocations for simple default values.
| |
| |     Don't allocate arrays when we are only assigning a single array key
| |     value.
| |
* |   commit c3f45e811e4b49fe27624b57c3eb8f4721a4323b
|\ \  Merge: 10e5734 43178fd
| |/  Author: Mark Story <[email protected]>
|/|   Date:   Mon Aug 29 22:15:30 2016 -0400
| |
| |       Merge pull request #9322 from cakephp/add-email-assertions
| |
| |       Add email assertions trait
| |
| * commit 43178fd55d7ef9a42706279fa275bb783063cf34
| | Author: Jad Bitar <[email protected]>
| | Date:   Mon Aug 29 17:43:29 2016 -0400
| |
| |     Fix `@since` in new files docblocks
| |

As you can see, only commits 8314c2ff833280bbc7102cb6d4fcf62240cd3ac4 and c3f45e811e4b49fe27624b57c3eb8f4721a4323b have the * being the first character in the commit lines. Those commits are from the master branch while the other four are from some other branches.

Solution 4:

The following shell command should do what you want:

git log --all --not $(git rev-list --no-walk --exclude=refs/heads/mybranch --all)

Caveats

If you have mybranch checked out, the above command won't work. That's because the commits on mybranch are also reachable by HEAD, so Git doesn't consider the commits to be unique to mybranch. To get it to work when mybranch is checked out, you must also add an exclude for HEAD:

git log --all --not $(git rev-list --no-walk \
    --exclude=refs/heads/mybranch \
    --exclude=HEAD \
    --all)

However, you should not exclude HEAD unless the mybranch is checked out, otherwise you risk showing commits that are not exclusive to mybranch.

Similarly, if you have a remote branch named origin/mybranch that corresponds to the local mybranch branch, you'll have to exclude it:

git log --all --not $(git rev-list --no-walk \
    --exclude=refs/heads/mybranch \
    --exclude=refs/remotes/origin/mybranch \
    --all)

And if the remote branch is the default branch for the remote repository (usually only true for origin/master), you'll have to exclude origin/HEAD as well:

git log --all --not $(git rev-list --no-walk \
    --exclude=refs/heads/mybranch \
    --exclude=refs/remotes/origin/mybranch \
    --exclude=refs/remotes/origin/HEAD \
    --all)

If you have the branch checked out, and there's a remote branch, and the remote branch is the default for the remote repository, then you end up excluding a lot:

git log --all --not $(git rev-list --no-walk \
    --exclude=refs/heads/mybranch \
    --exclude=HEAD
    --exclude=refs/remotes/origin/mybranch \
    --exclude=refs/remotes/origin/HEAD \
    --all)

Explanation

The git rev-list command is a low-level (plumbing) command that walks the given revisions and dumps the SHA1 identifiers encountered. Think of it as equivalent to git log except it only shows the SHA1—no log message, no author name, no timestamp, none of that "fancy" stuff.

The --no-walk option, as the name implies, prevents git rev-list from walking the ancestry chain. So if you type git rev-list --no-walk mybranch it will only print one SHA1 identifier: the identifier of the tip commit of the mybranch branch.

The --exclude=refs/heads/mybranch --all arguments tell git rev-list to start from each reference except for refs/heads/mybranch.

So, when you run git rev-list --no-walk --exclude=refs/heads/mybranch --all, Git prints the SHA1 identifier of the tip commit of each ref except for refs/heads/mybranch. These commits and their ancestors are the commits you are not interested in—these are the commits you do not want to see.

The other commits are the ones you want to see, so we collect the output of git rev-list --no-walk --exclude=refs/heads/mybranch --all and tell Git to show everything but those commits and their ancestors.

The --no-walk argument is necessary for large repositories (and is an optimization for small repositories): Without it, Git would have to print, and the shell would have to collect (and store in memory) many more commit identifiers than necessary. With a large repository, the number of collected commits could easily exceed the shell's command-line argument limit.

Git bug?

I would have expected the following to work:

git log --all --not --exclude=refs/heads/mybranch --all

but it does not. I'm guessing this is a bug in Git, but maybe it's intentional.