Git checkout by specific date doesn't work (ignores specified date and presents the whole commi-CodePudding

I have read very well-known link How to checkout in Git by date? the command git rev-list doesn't work for me - I am always getting the whole history of the commits, specified date time value seems to be ignored for my case.

Steps:
I am on my branch mynewbranch1

git log presents these commits:

**commit 1250c4c2 (HEAD -> mynewbranch1)**
Author: john <>
Date:   Tue May 10 11:27:45 2022  0200
    text1`

**commit ae99ff**
Author: john
Date:   Mon May 9 17:22:37 2022  0200
    text2`

**commit 84e85**
Author: alex <>
Date:   Mon May 9 16:13:47 2022  0200
    text3`

**commit 41b35**
Author: alex <>
Date:   Mon May 8 16:11:31 2022  0200
    text4`

Now I execute following command:

git checkout $(git rev-list -n 1 --first-parent --before="2022-05-09 16:13:47" mynewbranch1)

I tried also with backticks:

git checkout `git rev-list -n 1 --first-parent --before="2022-05-09 16:13:47" mynewbranch1`

Now I want to create a new branch from it:

git checkout -b some_branch_from_above_date

But when I execute git log on my new branch some_branch_from_above_date I can again see all the commits! I would expect to have only the 3rd and 4th commit from the above list because only those are before the specified date: 2022-05-09 16:13:47

I must do this through the script so I need to checkout by date! I even tried, for testing purposes, with string syntax -900 days ago but I still get recent commits! Please help!

git checkout -b mynewbranch2 `git rev-list -n 1 --before="900 days ago" mynewbranch1`

UPDATE THANKS TO @LeGEC Cause for this problem is because rev-list filters only based on CommitDate. While my AuthorDate is different because I set dat in git commit command explicitely with --date option. This is seen with git log --format=fuller command.

AuthorDate: Thu May 9 16:13:47 2022  0200
CommitDate: Wed May 11 13:48:07 2022  0200

CodePudding user response：

There is a known trap with commit dates :

a commit actually has two dates : the author date, and the committer date.

when an entirely new commit is created, it gets its author date and committer date set to now(),
for commands such as git commit --amend, git cherry-pick or git rebase, git creates new commits with a new committer/committer date, but preserves the author/author date from the "copied" commit.

And unfortunately : the date displayed by default by git log is the author date, but the date used in --before/--after filter is the committer date ...

AFAIK, there are currently only ways outside of git to filter by author date : see for example these two answers :

A quick way to see both dates explicitly is to use git log --format=fuller.

Or write a custom format string, using