Pjotr Prins <[email protected]> skribis: > When updating the commit hash to a different commit the git-fetch > derivation *does* change (I checked in guile), but the checked out git > tree in the store does not change - it gets shared between the > commits. I am not sure why the tree gets shared, but the effect is > that the same package gets installed using the same > /gnu/store/xxx-git-checkout.
This is expected: origins are fixed-output derivations, meaning that it does not matter how we perform them (using Git, over HTTP, or thanks to an avian carrier), as long as the result has the specified sha256. Thus, when you change, say, the Git commit ID or origin ‘method’ without changing the ‘sha256’ field, nothing happens: the daemon says “OK, I already have a store item with that ‘sha256’, so I don’t do anything.” Clearly, one has to be cautious with this, it’s easy to mistakenly use the old source. Hope this clarifies things! Ludo’.
