wip: Add constraint form for a precise unit-id

Author: mpickering

cabal-install-solver/src/Distribution/Solver/Modular/Message.hs

@@ -295,6 +295,7 @@ showFR _ UnknownPackage                   = " (unknown package)"
 showFR _ (GlobalConstraintVersion vr (ConstraintSourceProjectConfig pc)) = '\n' : (render . nest 6 $ docProjectConfigPathFailReason vr pc)
 showFR _ (GlobalConstraintVersion vr src) = " (" ++ constraintSource src ++ " requires " ++ prettyShow vr ++ ")"
 showFR _ (GlobalConstraintInstalled src)  = " (" ++ constraintSource src ++ " requires installed instance)"
+showFR _ (GlobalConstraintInstalledSpecificUnitId unitId src)  = " (" ++ constraintSource src ++ " requires installed instance with unit id " ++ prettyShow unitId ++ ")"
 showFR _ (GlobalConstraintSource src)     = " (" ++ constraintSource src ++ " requires source instance)"
 showFR _ (GlobalConstraintFlag src)       = " (" ++ constraintSource src ++ " requires opposite flag selection)"
 showFR _ ManualFlag                       = " (manual flag can only be changed explicitly)"

cabal-install-solver/src/Distribution/Solver/Modular/Package.hs

@@ -10,6 +10,7 @@ module Distribution.Solver.Modular.Package
   , PN
   , QPV
   , instI
+  , instUid
   , makeIndependent
   , primaryPP
   , setupPP
@@ -77,6 +78,10 @@ instI :: I -> Bool
 instI (I _ (Inst _)) = True
 instI _              = False
 
+instUid :: UnitId -> I -> Bool
+instUid uid (I _ (Inst uid')) = uid == uid'
+instUid _ _ = False
+
 -- | Is the package in the primary group of packages.  This is used to
 -- determine (1) if we should try to establish stanza preferences
 -- for this goal, and (2) whether or not a user specified @--constraint@

cabal-install-solver/src/Distribution/Solver/Modular/Preference.hs

@@ -190,6 +190,9 @@ processPackageConstraintP qpn c i (LabeledPackageConstraint (PackageConstraint s
     go _       PackagePropertyInstalled
         | instI i       = r
         | otherwise     = Fail c (GlobalConstraintInstalled src)
+    go _       (PackagePropertyInstalledSpecificUnitId unitId)
+        | instUid unitId i       = r
+        | otherwise     = Fail c (GlobalConstraintInstalledSpecificUnitId unitId src)
     go _       PackagePropertySource
         | not (instI i) = r
         | otherwise     = Fail c (GlobalConstraintSource src)

cabal-install-solver/src/Distribution/Solver/Modular/Tree.hs

@@ -118,6 +118,7 @@ data FailReason = UnsupportedExtension Extension
                 | UnknownPackage
                 | GlobalConstraintVersion VR ConstraintSource
                 | GlobalConstraintInstalled ConstraintSource
+                | GlobalConstraintInstalledSpecificUnitId UnitId ConstraintSource
                 | GlobalConstraintSource ConstraintSource
                 | GlobalConstraintFlag ConstraintSource
                 | ManualFlag

cabal-install-solver/src/Distribution/Solver/Types/PackageConstraint.hs

@@ -19,7 +19,7 @@ module Distribution.Solver.Types.PackageConstraint (
 import Distribution.Solver.Compat.Prelude
 import Prelude ()
 
-import Distribution.Package                        (PackageName)
+import Distribution.Package                        (PackageName, UnitId)
 import Distribution.PackageDescription             (FlagAssignment, dispFlagAssignment)
 import Distribution.Pretty                         (flatStyle, Pretty(pretty))
 import Distribution.Types.PackageVersionConstraint (PackageVersionConstraint (..))
@@ -90,6 +90,7 @@ instance Pretty ConstraintScope where
 data PackageProperty
    = PackagePropertyVersion   VersionRange
    | PackagePropertyInstalled
+   | PackagePropertyInstalledSpecificUnitId UnitId
    | PackagePropertySource
    | PackagePropertyFlags     FlagAssignment
    | PackagePropertyStanzas   [OptionalStanza]
@@ -101,6 +102,7 @@ instance Structured PackageProperty
 instance Pretty PackageProperty where
   pretty (PackagePropertyVersion verrange) = pretty verrange
   pretty PackagePropertyInstalled          = Disp.text "installed"
+  pretty (PackagePropertyInstalledSpecificUnitId unitId) = Disp.text "installed(" <> pretty unitId <> Disp.text ")"
   pretty PackagePropertySource             = Disp.text "source"
   pretty (PackagePropertyFlags flags)      = dispFlagAssignment flags
   pretty (PackagePropertyStanzas stanzas)  =
@@ -138,6 +140,7 @@ packageConstraintToDependency (PackageConstraint scope prop) = toDep prop
   where
     toDep (PackagePropertyVersion vr) = Just $ PackageVersionConstraint (scopeToPackageName scope) vr
     toDep (PackagePropertyInstalled)  = Nothing
+    toDep (PackagePropertyInstalledSpecificUnitId {}) = Nothing
     toDep (PackagePropertySource)     = Nothing
     toDep (PackagePropertyFlags _)    = Nothing
     toDep (PackagePropertyStanzas _)  = Nothing

cabal-install/src/Distribution/Client/Dependency.hs

@@ -98,6 +98,7 @@ import Distribution.Client.Utils
 import qualified Distribution.Compat.Graph as Graph
 import Distribution.Compiler
   ( CompilerInfo (..)
+  , AbiTag (..)
   )
 import Distribution.Package
   ( Package (..)
@@ -107,6 +108,8 @@ import Distribution.Package
   , mkPackageName
   , packageName
   , packageVersion
+  , UnitId
+  , mkUnitId
   )
 import qualified Distribution.PackageDescription as PD
 import Distribution.PackageDescription.Configuration
@@ -435,6 +438,19 @@ setSolverVerbosity verbosity params =
     { depResolverVerbosity = verbosity
     }
 
+dependOnSpecificCompiler :: CompilerInfo -> DepResolverParams -> DepResolverParams
+dependOnSpecificCompiler compiler params = addConstraints extraConstraints params
+  where
+    extraConstraints =
+      [ LabeledPackageConstraint
+        (PackageConstraint (ScopeAnyQualifier (mkPackageName "ghc")) (PackagePropertyInstalledSpecificUnitId (compilerIdToUnitId ghc_lib_abi)))
+        ConstraintSourceNonReinstallablePackage
+      | AbiTag ghc_lib_abi <- [compilerInfoAbiTag compiler]
+      ]
+
+    compilerIdToUnitId :: String -> UnitId
+    compilerIdToUnitId uid = mkUnitId (prettyShow (compilerInfoId compiler) ++ "-" ++ uid)
+
 -- | Some packages are specific to a given compiler version and should never be
 -- reinstalled.
 dontInstallNonReinstallablePackages :: DepResolverParams -> DepResolverParams
@@ -841,8 +857,8 @@ resolveDependencies platform comp pkgConfigDB params =
                     verbosity
                   ) =
         if asBool (depResolverAllowBootLibInstalls params)
-          then params
-          else dontInstallNonReinstallablePackages params
+          then dependOnSpecificCompiler comp params
+          else dontInstallNonReinstallablePackages (dependOnSpecificCompiler comp params)
 
     preferences :: PackageName -> PackagePreferences
     preferences = interpretPackagesPreference targets defpref prefs