Amend

Amend is a Git feature that allows developers to modify the most recent commit. It is commonly used to correct mistakes such as adding a missing file, fixing an incorrect commit message, or making minor adjustments without creating an entirely new commit.

This feature is particularly helpful for maintaining a clean and concise commit history, ensuring that changes are logically grouped and easy to understand.

Syntax

The syntax for using the amend feature in Git is:

git commit --amend

To amend both the content of the commit and the commit message, the following would be used:

git commit --amend -m "Your new commit message"

Example 1

Suppose, the developer created and committed a feature, but forgot to include a file:

# Original commit
echo "Initial code" > feature.txt
echo "Forgotten content" > forgotten-file.txt
git add feature.txt # Dev forgot to add forgotten-file.txt
git commit -m "Add initial code for the feature"

Here’s the original commit history:

git log --oneline
abc1234 Add initial code for the feature

The developer realized that he hasn’t included a file in the original commit. So, he performs the amend operation to both include the file in that commit and change the commit message:

# Amending the original commit
git add forgotten-file.txt
git commit --amend -m "Add initial code for the feature and forgotten file"

Here’s the amended commit history:

git log --oneline
def5678 Add initial code for the feature and forgotten file # Commit abc1234 has been replaced by def5678

Example 2

Suppose, the developer is going through another commit history:

git log --oneline
abc1234 Original commit message

While going through it, the developer didn’t like the above commit message. So, he decides to use the amend operation to only change the commit message without touching the contents of the commit:

git commit --amend -m "Corrected commit message"

Here’s the amended commit history:

git log --oneline
abc1234 Corrected commit message

Note: Use git commit --amend carefully if the commit has already been shared with others, as it rewrites history.