There isn't anything to compare. Nothing to compare, branches are entirely different commit histories

Question

I have a CMS theme installed on my machine. I\'m tracking changes to it via git and decided to back it up on GitHub so I could share those changes.

The theme as prov

Answer 1

I had an issue where I was pushing to my remote repo from a local repo that didn't match up with history of remote. This is what worked for me.

I cloned my repo locally so I knew I was working with fresh copy of repo:

git clone Your_REPO_URL_HERE.git

Switch to the branch you are trying to get into the remote:

git checkout Your_BRANCH_NAME_HERE

Add the remote of the original:

git remote add upstream Your_REMOTE_REPO_URL_HERE.git

Do a git fetch and git pull:

git fetch --all

git pull upstream Your_BRANCH_NAME_HERE

If you have merge conflicts, resolve them with

git mergetool kdiff3 

or other merge tool of your choice.

Once conflicts are resolved and saved. Commit and push changes.

Now go to the gitub.com repo of the original and attempt to create a pull request. You should have option to create pull request and not see the "Nothing to compare, branches are entirely different commit histories" Note: You may need to choose compare across forks for your pull request.

Answer 2

I had mine solved by overriding the branch:

My case: I wanted to override whatever code is in the develop with version_2.

1. delete the local copy of conflicting branch:

git checkout version_2
git branch -D develop

2. checkout a fresh branch from the version_2 and force push to git:

git checkout -b `develop`
git push origin `develop`

I didn't need to rebase. But in my case, I didn't need to take code from my old code.

Answer 3

I found that none of the answers provided actually worked for me; what actually worked for me is to do:

git push --set-upstream origin *BRANCHNAME*

After creating a new branch, then it gets tracked properly. (I have Git 2.7.4)

Answer 4

I got this error message, because I was migrating an application from SVN to GitHub and it's not enough to invoke a git init in the location of the source code checked out from SVN, but you need to invoke a git svn clone in order to have all the commit history. This way the two source codes on GitHub will have a mutual history and I was able to open pull requests.

Answer 5

I wanted to copy commit history of "master" branch & overwrite the commit history of "main" branch .
The steps are:-

1. git checkout master
2. git branch main master -f
3. git checkout main
4. git push

To delete master branch:-

a. Locally:-

5. git checkout main
6. git branch -d master

b. Globally:-

7. git push origin --delete master

Do Upvote it!

Answer 6

The Short Answer

It looks like GitHub won't let you compare the branches because they don't actually share any of the same history at all, even though they may share much of the same files and code.

Here is a screenshot of the temporary fork I made of your repo, where I tried to compare master with the upstreambranch, like you described. Notice the error message:

It says:

There isn't anything to compare.

master and upstreambranch are entirely different commit histories.

The Long Answer

You probably downloaded the original source and added it to a completely new repo instead of cloning the original repo, right? Doing that will make it so that the history of your repo will be completely different from the history of the original repo, since your new repo won't have any of the same commits with the same sha IDs.

You can see that by doing a reverse log of your master branch and the upstreambranch:

# Your first commit, see commit sha
git log --reverse master
commit c548d7b1b16b0350d7fbdb3ff1cfedcb38051397 # <== HERE
Author: Padraic Stack <padraic.stack@nuim.ie>
Date:   Wed Apr 2 15:11:28 2014 +0100

    First commit of everything

# First commit sha of the original repo
git log --reverse upstreambranch
commit 105a12817234033c45b4dc7522ff3103f473a862 # <== THERE
Author: Jeremy Boggs <jeremy@clioweb.org>
Date:   Mon Feb 22 16:00:53 2010 +0000

    Creates repo directories for the Seasons theme.

Solutions

If you redo your commits on top of the original history, you should then be able to compare the branches. There are several different ways that you can redo your commits, including

git rebase --onto

and

git cherry-pick

You also can redo each commit manually, if you have to.