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Also, why are the two timestamps so far off? Authored in February 2015 (almost a year ago!), but committed only in Nov 2015.

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This is a git repo, so "authored" tries to map to the person who wrote the content, and the "idea" of the commit, if there is such a thing. It's set when the commit is initially created, and for the most part not changed unless explicitly requested. The commit date is the actual time the commit object was made; this can differ if the commit is amended, rebased, cherry-picked, the result of a squash/fixup, etc. If a commit sits on a branch for months, then gets rebased against master, code-reviewed, and merged, those two dates will be significantly different.

This usually works as you might expect. If your coworker Joe authors a commit on a branch, and you cherry-pick it onto another branch, that cherry-picked commit is authored by Joe (and the time reflects when Joe authored it) and commited by you (at the time you performed the cherry-pick).

First, read my response to the other person who provided a technical answer to this question.

https://news.ycombinator.com/item?id=10806642

You have gone a little further and provided some general reasons as to "why this might happen", but you still seem to have missed the essence of the question, which was almost certainly more "can someone come up with some guess why, in this particular circumstance, given the theories about this commit being influenced by a settlement of the Oracle lawsuit, this commit was authored in February but only landed in November?".

Maybe because this has been ready for a long time just in case and they just decided to actually switch to that strategy right now?

This means that a person named Piotr Jastrzebski created a commit in February. This is a different commit based on that one (not in the sense of revision ancestry, but in the sense of rewrite history): this commit is the N-th rewrite of Piotr's Jasterbski's commit, for some N > 0, and the rewriter ("committer") is Narayan Kamath.

The rewrite can have different content: for instance, it can be altered to merge against a different parent.

An example of a rewrite is a simple cherry-pick (e.g. from one branch to another).

All these things are commits. The initial authoring is a commit, and this latest rewrite by a different person is a commit.

You have answered how it is possible, not why it happened: that is like someone pointing out that this "mysterious" commit is actually quite easy to explain, as a commit is an object in a git database, and we have all the metadata to see who made this one: I am extremely well aware of how it works (I give lectures at UCSB about git where I start by explaining the internal file formats and work my way up to the various command line tools), but I still found the question here of "why was this authored in February but only landed in November" fascinating, given the speculation about Oracle.

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