identical git commits having different hashes?

gistfile1.txt

This doesn't make any sense to me. I thought two identical diffs would have identical commit ids in git. But, this does not appear to be the case, as I have made two commits which are otherwise the same. I did this by rebasing two branches off the same branch. I feel like the intermediate commits should have been the same, but then I saw a fork in my tree. See below:

(venv)Kyle-Mulkas-MacBook-Pro:tchat.io mulka$ git show 6d5aaae49d6 > 1
(venv)Kyle-Mulkas-MacBook-Pro:tchat.io mulka$ git show 79a47534655 > 2
(venv)Kyle-Mulkas-MacBook-Pro:tchat.io mulka$ diff 1 2
1c1
< commit 6d5aaae49d66d9cfa95c5340ef8562f876694758
---
> commit 79a47534655e4afbfebbcb354adeb59943ca7edc
(venv)Kyle-Mulkas-MacBook-Pro:tchat.io mulka$

Git rebase? I thought it changes the commit hash.

Maybe this bears light? http://stackoverflow.com/questions/5144776/git-rebase-unexpected-mismatch-of-my-hashes

I do not know, but I'd assume it has to do with the commit time as part of the hash algorithm.

Or maybe not the date, but I think the hash is a bunch of stuff, not just the text content, like branch hierarchy, etc.

The date, and parent commit hashes are part of the hash of a particular commit