How can I reset or revert a file to a specific revision with Git?

To reset or revert a file to a specific revision in Git, use one of the following methods:

1. Reset a File to a Specific Commit

Replace the current version of the file with its state from a specific commit (e.g., abc1234):

git checkout abc1234 -- path/to/file.txt
# OR (modern Git)
git restore --source abc1234 -- path/to/file.txt

2. Reset to the Last Commit (HEAD)

Discard local changes and revert the file to the last commit:

git checkout HEAD -- path/to/file.txt
# OR
git restore path/to/file.txt

3. Revert to a Previous Commit (Create a New Undo Commit)

If you want to preserve history and create a new commit that undoes changes:

git revert abc1234 -- path/to/file.txt
# Follow the prompts to create a new commit

4. Preview File Content from a Specific Revision

View the file’s content at a specific commit without modifying your working directory:

git show abc1234:path/to/file.txt

Key Notes

• Commit Hash: Replace abc1234 with the actual commit hash (use git log to find it).
• Paths: Use the correct file path (relative to the repository root).
• Staged Changes: To unstage a file and reset it, add --staged:

  git restore --staged --source abc1234 -- path/to/file.txt

Example Workflow

1. Find the target commit:

   git log --oneline -- path/to/file.txt
   # Example output:
   # abc1234 Fix file.txt
   # def5678 Update file.txt

2. Reset the file to commit abc1234:

   git checkout abc1234 -- path/to/file.txt

3. Commit the reverted file:

   git commit -m "Revert file.txt to commit abc1234"

Summary Table

Command	Use Case
git checkout <commit> -- <file>	Reset file to a specific commit (old syntax).
git restore --source <commit> -- <file>	Reset file (modern syntax).
git revert <commit> -- <file>	Create a new commit that undoes changes.
git show <commit>:<file>	Preview a file’s content from a commit.

By using these commands, you can safely revert files to previous states without affecting the rest of your repository.