[SOLVED] Pulling is not possible because you have unmerged files

Why do we get "error: Pulling is not possible because you have unmerged files"?

The other day I got this error message

error: Pulling is not possible because you have unmerged files. hint: Fix them up in the work tree, and then use 'git add/rm <file>' hint: as appropriate to mark resolution and make a commit. fatal: Exiting because of an unresolved conflict.

The error message "Pulling is not possible because you have unmerged files" is a response from Git when you attempt to execute a git pull operation while there are unresolved merge conflicts in your repository.

Let's break down the error message and its parts:

error: Pulling is not possible because you have unmerged files.
- This is the primary message Git provides to indicate that there's an ongoing merge conflict in the repository, and until it's resolved, you cannot pull new changes from a remote branch.
hint: Fix them up in the work tree, and then use 'git add/rm <file>'
- This is a hint from Git on how to resolve the issue. The "work tree" refers to your working directory where you make changes to files. The idea is to manually go to the files with conflicts, resolve those conflicts, and then use git add <filename> to stage those resolved files. If you've resolved a conflict by deciding to remove a file, you can use git rm <filename> to reflect this.
hint: as appropriate to mark resolution and make a commit.
- After resolving all the conflicts and staging the changes with git add or git rm, you should make a commit to finalize the merge resolution. This is important because until you commit the resolved changes, the merge conflict remains unresolved in the eyes of Git.
fatal: Exiting because of an unresolved conflict.
- This is a final note from Git, indicating that due to the unresolved merge conflict, it's halting the current operation (in this case, the pull operation) to prevent any further complications or data loss.

Possible Solutions

1. Resolving Merge Conflicts

When you encounter a merge conflict, Git will mark the problematic areas in the affected files with conflict markers (<<<<<<<, =======, and >>>>>>>). These markers delineate the differences between the branches that are being merged.

Open the conflicted files in a text editor and search for the conflict markers.

Manually edit the file to resolve the conflict. This often involves deciding which changes to keep, which to discard, or perhaps integrating changes from both branches.

Here is my sample index.html which contains some conflicts

BEFORE Resolving Conflicts

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Pulling is not possible because you have unmerged files</title>
</head>
<body>
    <h2>Let's create the error</h2>
    <p>You are about encounter the error: pulling is not possible because you have unmerged files</p>
<<<<<<< HEAD
    <p>Generating the error</p>
=======
    <p>First, create the feature branch</p>
>>>>>>> feature_branch
</body>
</html>

AFTER Resolving Conflicts

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Pulling is not possible because you have unmerged files</title>
</head>
<body>
    <h2>Let's create the error</h2>
    <p>You are about encounter the error: pulling is not possible because you have unmerged files</p>
    <p>Generating the error</p>
    <p>First, create the feature branch</p>
</body>
</html>

Once resolved, save the file. Stage the file with git add <filename>. After resolving and staging all conflicted files, commit the changes with git commit.

git add index.html
git commit -m "Accept both paragraphs"

2. Using Git Stash to Temporarily Save Changes

If you have changes in your working directory that you aren't ready to commit, and you need to switch tasks or pull down updates, you can use git stash to temporarily save your changes without committing them.

Run git stash to save your changes. This removes the changes from your working directory and places them in a temporary area.
Perform any other tasks, like pulling the latest updates.
To get your stashed changes back, use git stash apply. If you're certain you won't need the stashed changes again, you can use git stash pop which will apply the changes and remove them from the stash list.
Resolve any conflicts that might arise when applying stashed changes.

3. Resetting to a Previous Commit

If the merge conflict is too complex or you decide it's better to start from a known good state, you can reset your branch to a previous commit. Do note that this method can discard changes, so it should be used judiciously.

Identify the commit hash of the point you want to reset to. You can use git log to view the commit history.
Use git reset --hard <commit-hash> to reset your current branch and working directory to that commit. The --hard option will discard all changes in your working directory since that commit. If you want to keep the changes but just unapply them, use --soft instead.
If you had already pushed commits before the reset, and after resetting you wish to push again, you'll need to use git push -f (force push). However, be very cautious with this, especially if others are working on the same branch, as it can overwrite changes on the remote.

Summary

The error, "Pulling is not possible because you have unmerged files," often results from attempting to git pull changes without resolving local merge conflicts.

In the dynamic and collaborative world of software development, keeping your codebase updated is not just a best practice but an essential one. Regularly updating local repositories ensures that developers are always working with the most recent and stable versions of the code, minimizing discrepancies and preventing the emergence of major conflicts down the line.

Unmerged files in a repository can be likened to unresolved disputes in a team project. They hinder progress, can cause confusion, and if left unaddressed, may lead to larger issues that are much harder to untangle. By making it a habit to resolve these unmerged files promptly, developers can ensure a smoother workflow, reduce the risk of data loss, and foster a more harmonious collaborative environment.

Thus, as we navigate the intricate web of codes and commits, it's vital to remember the foundational principles: Keep your local repositories updated and address unmerged files head-on. In doing so, not only do we maintain the integrity and consistency of our projects, but we also set the stage for more efficient and streamlined development processes in the future.