Does a commit object always have exactly one tree object?

I can't think of a scenario where it wouldn't be the case but I also can't see any documentation that explicitly states it.

CodePudding user response：

Does a commit object always have exactly one [top-level] tree object?

Yes.

I can't think of a scenario where it wouldn't be the case but I also can't see any documentation that explicitly states it.

It's part of the design: without it, git rev-parse commit^{tree} would not have an unambiguous result.

One can envision a system related to Git in which commits can store multiple trees,¹ but a number of design issues would need to be resolved first.

¹I've thought about this in several contexts, including the "submodules are wrong, subtrees are better but need better support" one. I have not resolved everything.