How do I revert all local changes in Git managed project to previous state?

To restore all local changes in a Git-managed project to a previous state, several methods are typically available. Here, I will detail three common approaches:

1. Using git reset

git reset is a powerful tool for undoing local modifications. If you need to revert your codebase to a specific commit, use the following command:

bash
 git reset --hard <commit_hash>

Here, <commit_hash> represents the hash of the commit you wish to return to. This command moves the current branch's HEAD to the specified commit and resets all files in the working directory to that commit's state.

Example: Suppose, while working, I accidentally deleted essential code and introduced inappropriate changes. I can locate the hash of the commit I want to revert to and apply the git reset --hard command to undo these alterations.

2. Using git checkout

If you only need to temporarily inspect an older state without permanently switching to it, use the git checkout command:

bash
 git checkout <commit_hash>

This does not alter the current branch's HEAD; instead, it temporarily switches your working directory to that commit. This method is ideal when you want to review an earlier version without discarding your current work.

Example: During project development, I needed to examine the previous version's implementation to compare differences with the current state. Using git checkout, I could quickly switch to that state, retrieve the necessary information, and then revert to my ongoing work.

3. Using git revert

When you must undo a specific commit while preserving subsequent commits, use git revert:

bash
 git revert <commit_hash>

This command creates a new commit that reverses the specified commit. Consequently, your project history remains continuous, but the changes from that commit are effectively undone.

Example: Suppose I discovered that an earlier commit introduced a critical error, and subsequent commits depend on it. Using git reset alone would discard all later changes, so I opted for git revert to undo the erroneous commit while retaining valid development progress.

Summary

The method you choose depends on your specific requirements, such as whether to preserve subsequent commits or to temporarily inspect an older state. In practice, selecting the appropriate approach among reset, checkout, or revert can effectively help you manage your project's version history.