Commit id changed to 11 digits from 7 digits.

Question

I moved a git repository present in one stash instance to another by first cloning it using git clone --mirror command and then using git push --mirror command.

After doing so, I noticed that commit id has changed to 11 digits in new stash instance instead of 7 digits present earlier.

The new format seems like to be the 
+<new_4_digit>.

Can you please let me know the reason behind this?

Mike Friedrich · Accepted Answer

My commit hashes are 40 digits long. the short versions still 7 (git bash command line).

The short versions are for display only, you should not rely on their length. Where do you have a problem with this?

The length of the short version is typically chosen so that you do not have collisions / duplicates in large projects. I just checked our Stash and it also has 11 digits for the short hash. You will note that this is used for a nicer display only, when you click on such a hash code link, it uses the long form in the link and internally.

Please see this:

https://git-scm.com/book/en/v2/Git-Tools-Revision-Selection#Short-SHA-1