Timestamp When Git Rebase Modifies the Commit Order

Table of Contents

Summary: If git rebase command switches some commits, the commit order is modified. This means the commits are not ordered by time in git history.

In this example, timestamp of three commits are below.

Third commit: 15:03:10
Second commit 15:02:49
Initial commit 15:02:34

git log

# commit 10bcb79e99dde756b16e74a3d27a26ea779a925c (HEAD -> main)
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:03:10 2024 +0900

#     Third commit

# commit 9c5a4d0ff35c9d960da8a0aba916613e05e6385f
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:02:49 2024 +0900

#     Second commit

# commit 0f76eb1e98f8c5071f3884587b3106f91b0a5c7a
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:02:34 2024 +0900

#     Initial commit

Let’s switch the second and third commits by using git rebase command.

 git rebase -i HEAD~2

# Modify from
pick 9c5a4d0 Second commit
pick 10bcb79 Third commit

# to
pick 10bcb79 Third commit
pick 9c5a4d0 Second commit

# then save and close the editor

We can see the second and third commits are switched, which means the timestamp of commits are not ordered by time in git history.

Second commit 15:02:49
Third commit: 15:03:10
Initial commit 15:02:34

git log

# commit 4f2c5197b69a7cc2c677e53f2d9817efa74d4103 (HEAD -> main)
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:02:49 2024 +0900

#     Second commit

# commit 7429f56400a5134874aeb8fa05bfb58b4fe36b2c
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:03:10 2024 +0900

#     Third commit

# commit 0f76eb1e98f8c5071f3884587b3106f91b0a5c7a
# Author: xxx <xxx@xxx.com>
# Date:   Sat Oct 12 15:02:34 2024 +0900

#     Initial commit