Ticket #884 (closed enhancement: fixed)
Changed dependencies in locally installed packages ignord
|Reported by:||nomeata||Owned by:||kosmikus|
in Debian, I have patched yesod-json-0.2.1 to depend on aeson instead of aeson-native, because we want only one aeson and blaze-textual package in Debian.
Still, if I use cabal install to install a package that depends on yesod-json, it wants to re-build yesod-json against the -native variants. It seems that cabal install does not take the actual dependencies of installed packages into account and uses the Hackage provided information for them as well.
What it should do instead is: If a dependency of some packages that is to be installed can be fulfilled by a locally installed package, and none of its dependencies (as known by ghc-pkg) have to be rebuild, then this package should be used. Only if the package in question has to be rebuild, the dependencies according to hackage should be taken into account.
The work around in Debian is to bump the version number, adding a vendor level (0.2.1.0.1), but it would be nice if this could be avoided.