avnyu

Done, the "extract code into update_db" part is a single commit now. I think the remains part needs to be in the same commit

Sorry for the late response, I force-pushed the commits. About new tests, if I am not mistaking, it should be only about the git db cache, not the correctness of...

> Overall looks like. Let me know if you plan to reorganize the commits, or I can do that for you. Thanks! > > _[View changes since this review](https://triagebot.infra.rust-lang.org/gh-changes-since/rust-lang/cargo/16246/334b7b6085fc5a09c275720af9439415d25d2212..a4747688e14a045c2e18c08e2ec81103a2cccb6c)_ If...