How to Check If a Git Commit Has Been Pushed

Introduction

In this lab, you will learn how to check if a Git commit has been pushed to a remote repository. We will explore different methods to achieve this, starting by fetching changes from a remote and using git log @{u} to compare local and remote branches.

You will then learn how to use git branch -r --contains to identify remote branches that contain a specific commit and finally verify the push status by directly inspecting the remote branch. This hands-on approach will provide you with practical skills to confidently determine the push status of your Git commits.

Skills Graph

Fetch Remote and Check git log @{u}

In this step, we will learn how to fetch changes from a remote repository and see how our local branch compares to the remote branch using git log @{u}.

First, let's simulate having a remote repository. In a real-world scenario, this would be on a platform like GitHub or GitLab, but for this lab, we'll use a local directory as our "remote".

Navigate to your project directory:

cd ~/project/my-time-machine

Now, let's add a remote named origin pointing to a simulated remote repository. We'll assume a remote repository was set up in the setup section.

git remote add origin ../my-time-machine-remote

This command tells your local Git repository that there's another repository located at ../my-time-machine-remote and we're calling it origin.

Now, let's fetch the latest changes from this remote. The git fetch command downloads commits, files, and refs from a remote repository into your local repository. It doesn't automatically merge or modify your current work.

git fetch origin

You should see output indicating that Git is fetching from the remote.

After fetching, we can use git log @{u} (or git log origin/master in this case, as origin/master is the upstream branch for master) to see the commits on the remote branch that are not yet on our local branch. The @{u} or @{upstream} syntax refers to the upstream branch of the current branch.

git log @{u}

Since our local master branch was created from scratch and the remote master branch (simulated) also started empty and we haven't added any commits to the remote yet, this command might not show any output, or it might show the initial commit if the remote was initialized with one. The important part is understanding what this command does: it shows the commits that are on the upstream branch (origin/master) but not on your current local branch (master).

Understanding the difference between your local branch and the remote branch is crucial for collaboration and keeping your project up-to-date. git fetch and git log @{u} are powerful tools for inspecting the state of the remote repository without changing your local working directory.

Use git branch -r --contains

In this step, we will explore how to use the git branch -r --contains command to find which remote branches contain a specific commit. This is useful when you want to know if a particular change has been included in a remote branch.

First, make sure you are in your project directory:

cd ~/project/my-time-machine

Now, let's create a new commit in our local repository. This will give us a commit to search for on the remote.

echo "Adding another message" >> message.txt
git add message.txt
git commit -m "Add another message"

You should see output confirming the new commit.

Now, let's use git log --oneline to see the history and get the commit hash of our latest commit.

git log --oneline

Copy the commit hash (the short string of characters) of the commit with the message "Add another message". It will look something like abcdefg.

Now, let's use git branch -r --contains with the commit hash you just copied. Replace YOUR_COMMIT_HASH with the actual hash.

git branch -r --contains YOUR_COMMIT_HASH

Since we haven't pushed this new commit to the remote repository (origin) yet, this command should not show origin/master in the output. This is because the remote branch origin/master does not yet contain the commit you just created locally.

The git branch -r part lists remote-tracking branches. The --contains YOUR_COMMIT_HASH part filters this list to only show branches that contain the specified commit.

This command is a powerful way to check the status of your commits relative to remote branches. It helps you understand if your changes have been integrated into the remote repository.

Verify with Remote Branch

In this final step, we will push our local commit to the remote repository and then use git branch -r --contains again to verify that the remote branch now contains our commit.

First, ensure you are in your project directory:

cd ~/project/my-time-machine

Now, let's push our local master branch to the origin remote.

git push origin master

You should see output indicating that your commit is being pushed to the remote repository.

After the push is complete, let's get the commit hash of the commit we want to verify. Use git log --oneline again:

git log --oneline

Copy the commit hash of the commit with the message "Add another message".

Now, use git branch -r --contains with the commit hash you just copied. Replace YOUR_COMMIT_HASH with the actual hash.

git branch -r --contains YOUR_COMMIT_HASH

This time, you should see origin/master in the output. This confirms that your commit has been successfully pushed to the remote repository and the remote branch origin/master now contains this commit.

This process of pushing your changes and then verifying them on the remote branch is a common workflow in Git, especially when collaborating with others. It ensures that your contributions are available to the rest of the team.

You have now successfully fetched from a remote, used git branch -r --contains to check for a commit, pushed your changes, and verified the commit on the remote branch. These are essential skills for working with remote repositories in Git.

Summary

In this lab, we learned how to check if local Git commits have been pushed to a remote repository. We began by simulating a remote repository and adding it as an origin remote to our local project. We then used git fetch origin to retrieve the latest information from the remote without modifying our local working state.

Following the fetch, we explored the git log @{u} command, which is a powerful way to compare our local branch with its configured upstream branch (in this case, origin/master). This command helps visualize commits that exist on the remote but not locally, providing insight into the synchronization status of our branch. While the initial output might be empty if no commits have been pushed, understanding this command is crucial for identifying commits that are yet to be shared with the remote.