Git - how to find first commit of specific branch

In following example tree:

A-B-C-D-E (master branch)
    \
     F-G-H (xxx branch)

I'm looking for F - the first commit in xxx branch. I think that it is possible with:

git log xxx --not master

and the last listed commit should be F. Is it correct solution or maybe there are some disadvantages of it?

I know that there were similar questions on stackoverflow, but nobody proposed such solution, and I'm not sure if I do it right.

git log master..branch --oneline | tail -1

Where "branch" is your specific branch name. The dot-dot gives you all of the commits that the branch has that master doesn't have. tail -1 returns the last line from the previous output.

You should use the merge-base functionality which is designed to solve exactly this:

git merge-base remotes/origin/<branch> develop

git cherry master -v | head -n 1

cherry - Shows the commits on your current branch that aren't present on a branch upstream (docs). An upstream (master in this case) is a point your current branch derives from.

-v - Shows commit names (instead of just SHA's) - verbose.

head - Unix command which prints n number of lines from a text

If your branch (old one) once again merged back to master doesn't give expected result.I have using python script to find initial branch commit Id.

git rev-list --first-parent changeset

--first-parent follow only the first parent commit upon seeing a merge commit.

Iterate changeset's from above command until parent branch found.

def status_check(exec_command, exec_dir=None, background=False):
    if exec_dir:
        os.chdir(exec_dir)
    res = subprocess.Popen(exec_command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    if not background:
        result = res.communicate()
    return result



def findNewBranchCommits(changeset=None):
    cmd = "git rev-list --first-parent "+ changeset
    rev_list = status_check(cmd,self.module_dir)
    rev_list = str(rev_list[0]).split('\n')
    rev_list = list(filter(None, rev_list))
    for x in rev_list:                      # Iterate until branch base point
        rev_cmd = "git branch --contains " + x
        rev_cmd = status_check(rev_cmd,self.module_dir)
        rev_cmd = str(rev_cmd[0]).split('\n')
        if(len(rev_cmd) > 2): 
            print "First Commit in xxx branch",x
            break

findNewBranchCommits(changeset)

Git - how to find first commit of specific branch

Related

Recent Posts