Fix package dependencies (Trac #657)
This fixes Trac #654.
There are only two important changes.
- The first one fixes missing dependencies:
diff -pkgDependencies = fmap (fmap PD.dependencies) . readPackageDataFile +pkgDependencies = fmap (fmap (map pkgName . packageDependencies)) . readCabalFile
Here PD.dependencies returned versioned package names, e.g. ghc-8.7, which then failed to match with non-versioned package names such as ghc in contextDependencies. Switching from PD.dependencies to packageDependencies fixes this.
- I clearly remember that we didn't have this bug before, so I added some tests for our package dependency infrastructure to prevent such regressions in future:
haskell testDependencies :: Action () testDependencies = do putBuild "==== pkgDependencies" depLists <- mapM (pkgDependencies . vanillaContext Stage1) ghcPackages test $ and [ deps == sort deps | Just deps <- depLists ] putBuild "==== Dependencies of the 'ghc-bin' binary" ghcDeps <- pkgDependencies (vanillaContext Stage1 ghc) test $ isJust ghcDeps test $ pkgName compiler `elem` fromJust ghcDeps stage0Deps <- contextDependencies (vanillaContext Stage0 ghc) stage1Deps <- contextDependencies (vanillaContext Stage1 ghc) stage2Deps <- contextDependencies (vanillaContext Stage2 ghc) test $ vanillaContext Stage0 compiler `notElem` stage1Deps test $ vanillaContext Stage1 compiler `elem` stage1Deps test $ vanillaContext Stage2 compiler `notElem` stage1Deps test $ stage1Deps /= stage0Deps test $ stage1Deps == stage2Deps
Everything else are cosmetic changes, fixing minor issues in comments, and adding TODOs. To figure out the failure in Trac #654 I had to read some code I didn't write and my hands were automatically fixing some style inconsistencies with the rest of the Hadrian code base. (I'd like to emphasise that I make no judgement about which style is better, it's merely an attempt to make the code base look more homogeneous, which I think is useful.)