cabal-install-2.0.0.1: Distribution/Solver/Modular/IndexConversion.hs
module Distribution.Solver.Modular.IndexConversion
( convPIs
) where
import Data.List as L
import Data.Map as M
import Data.Maybe
import Data.Monoid as Mon
import Data.Set as S
import Prelude hiding (pi)
import Distribution.Compiler
import Distribution.InstalledPackageInfo as IPI
import Distribution.Package -- from Cabal
import Distribution.Simple.BuildToolDepends -- from Cabal
import Distribution.Simple.Utils (cabalVersion) -- from Cabal
import Distribution.Types.ExeDependency -- from Cabal
import Distribution.Types.PkgconfigDependency -- from Cabal
import Distribution.Types.ComponentName -- from Cabal
import Distribution.Types.UnqualComponentName -- from Cabal
import Distribution.Types.CondTree -- from Cabal
import Distribution.Types.MungedPackageId -- from Cabal
import Distribution.Types.MungedPackageName -- from Cabal
import Distribution.PackageDescription as PD -- from Cabal
import Distribution.PackageDescription.Configuration as PDC
import qualified Distribution.Simple.PackageIndex as SI
import Distribution.System
import Distribution.Types.ForeignLib
import Distribution.Solver.Types.ComponentDeps
( Component(..), componentNameToComponent )
import Distribution.Solver.Types.Flag
import Distribution.Solver.Types.OptionalStanza
import qualified Distribution.Solver.Types.PackageIndex as CI
import Distribution.Solver.Types.Settings
import Distribution.Solver.Types.SourcePackage
import Distribution.Solver.Modular.Dependency as D
import Distribution.Solver.Modular.Flag as F
import Distribution.Solver.Modular.Index
import Distribution.Solver.Modular.Package
import Distribution.Solver.Modular.Tree
import Distribution.Solver.Modular.Version
-- | Convert both the installed package index and the source package
-- index into one uniform solver index.
--
-- We use 'allPackagesBySourcePackageId' for the installed package index
-- because that returns us several instances of the same package and version
-- in order of preference. This allows us in principle to \"shadow\"
-- packages if there are several installed packages of the same version.
-- There are currently some shortcomings in both GHC and Cabal in
-- resolving these situations. However, the right thing to do is to
-- fix the problem there, so for now, shadowing is only activated if
-- explicitly requested.
convPIs :: OS -> Arch -> CompilerInfo -> ShadowPkgs -> StrongFlags -> SolveExecutables ->
SI.InstalledPackageIndex -> CI.PackageIndex (SourcePackage loc) -> Index
convPIs os arch comp sip strfl sexes iidx sidx =
mkIndex (convIPI' sip iidx ++ convSPI' os arch comp strfl sexes sidx)
-- | Convert a Cabal installed package index to the simpler,
-- more uniform index format of the solver.
convIPI' :: ShadowPkgs -> SI.InstalledPackageIndex -> [(PN, I, PInfo)]
convIPI' (ShadowPkgs sip) idx =
-- apply shadowing whenever there are multiple installed packages with
-- the same version
[ maybeShadow (convIP idx pkg)
-- IMPORTANT to get internal libraries. See
-- Note [Index conversion with internal libraries]
| (_, pkgs) <- SI.allPackagesBySourcePackageIdAndLibName idx
, (maybeShadow, pkg) <- zip (id : repeat shadow) pkgs ]
where
-- shadowing is recorded in the package info
shadow (pn, i, PInfo fdeps fds _) | sip = (pn, i, PInfo fdeps fds (Just Shadowed))
shadow x = x
-- | Extract/recover the the package ID from an installed package info, and convert it to a solver's I.
convId :: InstalledPackageInfo -> (PN, I)
convId ipi = (pn, I ver $ Inst $ IPI.installedUnitId ipi)
where MungedPackageId mpn ver = mungedId ipi
-- HACK. See Note [Index conversion with internal libraries]
pn = mkPackageName (unMungedPackageName mpn)
-- | Convert a single installed package into the solver-specific format.
convIP :: SI.InstalledPackageIndex -> InstalledPackageInfo -> (PN, I, PInfo)
convIP idx ipi =
case mapM (convIPId pn idx) (IPI.depends ipi) of
Nothing -> (pn, i, PInfo [] M.empty (Just Broken))
Just fds -> (pn, i, PInfo (setComp fds) M.empty Nothing)
where
(pn, i) = convId ipi
-- 'sourceLibName' is unreliable, but for now we only really use this for
-- primary libs anyways
setComp = setCompFlaggedDeps $ componentNameToComponent
$ libraryComponentName $ sourceLibName ipi
-- TODO: Installed packages should also store their encapsulations!
-- Note [Index conversion with internal libraries]
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- Something very interesting happens when we have internal libraries
-- in our index. In this case, we maybe have p-0.1, which itself
-- depends on the internal library p-internal ALSO from p-0.1.
-- Here's the danger:
--
-- - If we treat both of these packages as having PN "p",
-- then the solver will try to pick one or the other,
-- but never both.
--
-- - If we drop the internal packages, now p-0.1 has a
-- dangling dependency on an "installed" package we know
-- nothing about. Oops.
--
-- An expedient hack is to put p-internal into cabal-install's
-- index as a MUNGED package name, so that it doesn't conflict
-- with anyone else (except other instances of itself). But
-- yet, we ought NOT to say that PNs in the solver are munged
-- package names, because they're not; for source packages,
-- we really will never see munged package names.
--
-- The tension here is that the installed package index is actually
-- per library, but the solver is per package. We need to smooth
-- it over, and munging the package names is a pretty good way to
-- do it.
-- | Convert dependencies specified by an installed package id into
-- flagged dependencies of the solver.
--
-- May return Nothing if the package can't be found in the index. That
-- indicates that the original package having this dependency is broken
-- and should be ignored.
convIPId :: PN -> SI.InstalledPackageIndex -> UnitId -> Maybe (FlaggedDep () PN)
convIPId pn' idx ipid =
case SI.lookupUnitId idx ipid of
Nothing -> Nothing
Just ipi -> let (pn, i) = convId ipi
in Just (D.Simple (Dep False pn (Fixed i (P pn'))) ())
-- NB: something we pick up from the
-- InstalledPackageIndex is NEVER an executable
-- | Convert a cabal-install source package index to the simpler,
-- more uniform index format of the solver.
convSPI' :: OS -> Arch -> CompilerInfo -> StrongFlags -> SolveExecutables ->
CI.PackageIndex (SourcePackage loc) -> [(PN, I, PInfo)]
convSPI' os arch cinfo strfl sexes = L.map (convSP os arch cinfo strfl sexes) . CI.allPackages
-- | Convert a single source package into the solver-specific format.
convSP :: OS -> Arch -> CompilerInfo -> StrongFlags -> SolveExecutables -> SourcePackage loc -> (PN, I, PInfo)
convSP os arch cinfo strfl sexes (SourcePackage (PackageIdentifier pn pv) gpd _ _pl) =
let i = I pv InRepo
in (pn, i, convGPD os arch cinfo strfl sexes (PI pn i) gpd)
-- We do not use 'flattenPackageDescription' or 'finalizePD'
-- from 'Distribution.PackageDescription.Configuration' here, because we
-- want to keep the condition tree, but simplify much of the test.
-- | Convert a generic package description to a solver-specific 'PInfo'.
convGPD :: OS -> Arch -> CompilerInfo -> StrongFlags -> SolveExecutables ->
PI PN -> GenericPackageDescription -> PInfo
convGPD os arch cinfo strfl sexes pi
(GenericPackageDescription pkg flags mlib sub_libs flibs exes tests benchs) =
let
fds = flagInfo strfl flags
-- | We have to be careful to filter out dependencies on
-- internal libraries, since they don't refer to real packages
-- and thus cannot actually be solved over. We'll do this
-- by creating a set of package names which are "internal"
-- and dropping them as we convert.
ipns = S.fromList $ [ unqualComponentNameToPackageName nm
| (nm, _) <- sub_libs ]
conv :: Mon.Monoid a => Component -> (a -> BuildInfo) ->
CondTree ConfVar [Dependency] a -> FlaggedDeps Component PN
conv comp getInfo = convCondTree pkg os arch cinfo pi fds comp getInfo ipns sexes .
PDC.addBuildableCondition getInfo
flagged_deps
= concatMap (\ds -> conv ComponentLib libBuildInfo ds) (maybeToList mlib)
++ concatMap (\(nm, ds) -> conv (ComponentSubLib nm) libBuildInfo ds) sub_libs
++ concatMap (\(nm, ds) -> conv (ComponentFLib nm) foreignLibBuildInfo ds) flibs
++ concatMap (\(nm, ds) -> conv (ComponentExe nm) buildInfo ds) exes
++ prefix (Stanza (SN pi TestStanzas))
(L.map (\(nm, ds) -> conv (ComponentTest nm) testBuildInfo ds) tests)
++ prefix (Stanza (SN pi BenchStanzas))
(L.map (\(nm, ds) -> conv (ComponentBench nm) benchmarkBuildInfo ds) benchs)
++ maybe [] (convSetupBuildInfo pi) (setupBuildInfo pkg)
-- | We infer the maximally supported spec-version from @lib:Cabal@'s version
--
-- As we cannot predict the future, we can only properly support
-- spec-versions predating (and including) the @lib:Cabal@ version
-- used by @cabal-install@.
--
-- This relies on 'cabalVersion' having always at least 3 components to avoid
-- comparisons like @2.0.0 > 2.0@ which would result in confusing results.
--
-- NOTE: Before we can switch to a /normalised/ spec-version
-- comparison (e.g. by truncating to 3 components, and removing
-- trailing zeroes) we'd have to make sure all other places where
-- the spec-version is compared against a bound do it
-- consistently.
maxSpecVer = cabalVersion
-- | Required/declared spec-version of the package
--
-- We don't truncate patch-levels, as specifying a patch-level
-- spec-version is discouraged and not supported anymore starting
-- with spec-version 2.2.
reqSpecVer = specVersion pkg
-- | A too-new specVersion is turned into a global 'FailReason'
-- which prevents the solver from selecting this release (and if
-- forced to, emit a meaningful solver error message).
fr | reqSpecVer > maxSpecVer = Just (UnsupportedSpecVer reqSpecVer)
| otherwise = Nothing
in
PInfo flagged_deps fds fr
-- | Create a flagged dependency tree from a list @fds@ of flagged
-- dependencies, using @f@ to form the tree node (@f@ will be
-- something like @Stanza sn@).
prefix :: (FlaggedDeps comp qpn -> FlaggedDep comp' qpn)
-> [FlaggedDeps comp qpn] -> FlaggedDeps comp' qpn
prefix _ [] = []
prefix f fds = [f (concat fds)]
-- | Convert flag information. Automatic flags are now considered weak
-- unless strong flags have been selected explicitly.
flagInfo :: StrongFlags -> [PD.Flag] -> FlagInfo
flagInfo (StrongFlags strfl) =
M.fromList . L.map (\ (MkFlag fn _ b m) -> (fn, FInfo b (flagType m) (weak m)))
where
weak m = WeakOrTrivial $ not (strfl || m)
flagType m = if m then Manual else Automatic
-- | Internal package names, which should not be interpreted as true
-- dependencies.
type IPNs = Set PN
-- | Convenience function to delete a 'FlaggedDep' if it's
-- for a 'PN' that isn't actually real.
filterIPNs :: IPNs -> Dependency -> FlaggedDep Component PN -> FlaggedDeps Component PN
filterIPNs ipns (Dependency pn _) fd
| S.notMember pn ipns = [fd]
| otherwise = []
-- | Convert condition trees to flagged dependencies. Mutually
-- recursive with 'convBranch'. See 'convBranch' for an explanation
-- of all arguments preceeding the input 'CondTree'.
convCondTree :: PackageDescription -> OS -> Arch -> CompilerInfo -> PI PN -> FlagInfo ->
Component ->
(a -> BuildInfo) ->
IPNs ->
SolveExecutables ->
CondTree ConfVar [Dependency] a -> FlaggedDeps Component PN
convCondTree pkg os arch cinfo pi@(PI pn _) fds comp getInfo ipns sexes@(SolveExecutables sexes') (CondNode info ds branches) =
concatMap
(\d -> filterIPNs ipns d (D.Simple (convLibDep pn d) comp))
ds -- unconditional package dependencies
++ L.map (\e -> D.Simple (Ext e) comp) (PD.allExtensions bi) -- unconditional extension dependencies
++ L.map (\l -> D.Simple (Lang l) comp) (PD.allLanguages bi) -- unconditional language dependencies
++ L.map (\(PkgconfigDependency pkn vr) -> D.Simple (Pkg pkn vr) comp) (PD.pkgconfigDepends bi) -- unconditional pkg-config dependencies
++ concatMap (convBranch pkg os arch cinfo pi fds comp getInfo ipns sexes) branches
-- build-tools dependencies
-- NB: Only include these dependencies if SolveExecutables
-- is True. It might be false in the legacy solver
-- codepath, in which case there won't be any record of
-- an executable we need.
++ [ D.Simple (convExeDep pn exeDep) comp
| sexes'
, exeDep <- getAllToolDependencies pkg bi
, not $ isInternal pkg exeDep
]
where
bi = getInfo info
-- | Branch interpreter. Mutually recursive with 'convCondTree'.
--
-- Here, we try to simplify one of Cabal's condition tree branches into the
-- solver's flagged dependency format, which is weaker. Condition trees can
-- contain complex logical expression composed from flag choices and special
-- flags (such as architecture, or compiler flavour). We try to evaluate the
-- special flags and subsequently simplify to a tree that only depends on
-- simple flag choices.
--
-- This function takes a number of arguments:
--
-- 1. Some pre dependency-solving known information ('OS', 'Arch',
-- 'CompilerInfo') for @os()@, @arch()@ and @impl()@ variables,
--
-- 2. The package instance @'PI' 'PN'@ which this condition tree
-- came from, so that we can correctly associate @flag()@
-- variables with the correct package name qualifier,
--
-- 3. The flag defaults 'FlagInfo' so that we can populate
-- 'Flagged' dependencies with 'FInfo',
--
-- 4. The name of the component 'Component' so we can record where
-- the fine-grained information about where the component came
-- from (see 'convCondTree'), and
--
-- 5. A selector to extract the 'BuildInfo' from the leaves of
-- the 'CondTree' (which actually contains the needed
-- dependency information.)
--
-- 6. The set of package names which should be considered internal
-- dependencies, and thus not handled as dependencies.
convBranch :: PackageDescription -> OS -> Arch -> CompilerInfo ->
PI PN -> FlagInfo ->
Component ->
(a -> BuildInfo) ->
IPNs ->
SolveExecutables ->
CondBranch ConfVar [Dependency] a ->
FlaggedDeps Component PN
convBranch pkg os arch cinfo pi@(PI pn _) fds comp getInfo ipns sexes (CondBranch c' t' mf') =
go c' ( convCondTree pkg os arch cinfo pi fds comp getInfo ipns sexes t')
(maybe [] (convCondTree pkg os arch cinfo pi fds comp getInfo ipns sexes) mf')
where
go :: Condition ConfVar ->
FlaggedDeps Component PN -> FlaggedDeps Component PN -> FlaggedDeps Component PN
go (Lit True) t _ = t
go (Lit False) _ f = f
go (CNot c) t f = go c f t
go (CAnd c d) t f = go c (go d t f) f
go (COr c d) t f = go c t (go d t f)
go (Var (Flag fn)) t f = extractCommon t f ++ [Flagged (FN pi fn) (fds ! fn) t f]
go (Var (OS os')) t f
| os == os' = t
| otherwise = f
go (Var (Arch arch')) t f
| arch == arch' = t
| otherwise = f
go (Var (Impl cf cvr)) t f
| matchImpl (compilerInfoId cinfo) ||
-- fixme: Nothing should be treated as unknown, rather than empty
-- list. This code should eventually be changed to either
-- support partial resolution of compiler flags or to
-- complain about incompletely configured compilers.
any matchImpl (fromMaybe [] $ compilerInfoCompat cinfo) = t
| otherwise = f
where
matchImpl (CompilerId cf' cv) = cf == cf' && checkVR cvr cv
-- If both branches contain the same package as a simple dep, we lift it to
-- the next higher-level, but without constraints. This heuristic together
-- with deferring flag choices will then usually first resolve this package,
-- and try an already installed version before imposing a default flag choice
-- that might not be what we want.
--
-- Note that we make assumptions here on the form of the dependencies that
-- can occur at this point. In particular, no occurrences of Fixed, and no
-- occurrences of multiple version ranges, as all dependencies below this
-- point have been generated using 'convLibDep'.
--
-- WARNING: This is quadratic!
extractCommon :: FlaggedDeps Component PN -> FlaggedDeps Component PN -> FlaggedDeps Component PN
extractCommon ps ps' = [ D.Simple (Dep is_exe1 pn1 (Constrained [(vr1 .||. vr2, P pn)])) comp
| D.Simple (Dep is_exe1 pn1 (Constrained [(vr1, _)])) _ <- ps
, D.Simple (Dep is_exe2 pn2 (Constrained [(vr2, _)])) _ <- ps'
, pn1 == pn2
, is_exe1 == is_exe2
]
-- | Convert a Cabal dependency on a library to a solver-specific dependency.
convLibDep :: PN -> Dependency -> Dep PN
convLibDep pn' (Dependency pn vr) = Dep False {- not exe -} pn (Constrained [(vr, P pn')])
-- | Convert a Cabal dependency on a executable (build-tools) to a solver-specific dependency.
-- TODO do something about the name of the exe component itself
convExeDep :: PN -> ExeDependency -> Dep PN
convExeDep pn' (ExeDependency pn _ vr) = Dep True pn (Constrained [(vr, P pn')])
-- | Convert setup dependencies
convSetupBuildInfo :: PI PN -> SetupBuildInfo -> FlaggedDeps Component PN
convSetupBuildInfo (PI pn _i) nfo =
L.map (\d -> D.Simple (convLibDep pn d) ComponentSetup) (PD.setupDepends nfo)