core: add System.Nix.Realisation

hnix-store-core/hnix-store-core.cabal

@@ -66,6 +66,7 @@ library
     , System.Nix.Hash
     , System.Nix.Hash.Truncation
     , System.Nix.OutputName
+    , System.Nix.Realisation
     , System.Nix.Signature
     , System.Nix.Store.Types
     , System.Nix.StorePath

hnix-store-core/src/System/Nix/Realisation.hs

@@ -0,0 +1,41 @@
+{-|
+Description : Derivation realisations
+-}
+
+module System.Nix.Realisation (
+    DerivationOutput(..)
+  , Realisation(..)
+  ) where
+
+import Crypto.Hash (Digest)
+import Data.Map (Map)
+import Data.Set (Set)
+import Data.Dependent.Sum (DSum)
+import GHC.Generics (Generic)
+import System.Nix.Hash (HashAlgo)
+import System.Nix.OutputName (OutputName)
+import System.Nix.Signature (Signature)
+import System.Nix.StorePath (StorePath)
+
+-- | Output of the derivation
+data DerivationOutput outputName = DerivationOutput
+  { derivationOutputHash :: DSum HashAlgo Digest
+  -- ^ Hash modulo of the derivation
+  , derivationOutputName :: outputName
+  -- ^ Name of the output
+  } deriving (Eq, Generic, Ord, Show)
+
+-- | Build realisation context
+--
+-- realisationId is ommited since it is a key
+-- of type @DerivationOutput OutputName@ so
+-- we will use a tuple like @(DerivationOutput OutputName, Realisation)@
+-- instead.
+data Realisation = Realisation
+  { realisationOutPath :: StorePath
+  -- ^ Output path
+  , realisationSignatures :: Set Signature
+  -- ^ Signatures
+  , realisationDependencies :: Map (DerivationOutput OutputName) StorePath
+  -- ^ Dependent realisations required for this one to be valid
+  } deriving (Eq, Generic, Ord, Show)

hnix-store-tests/hnix-store-tests.cabal

@@ -47,6 +47,7 @@ library
     , System.Nix.Arbitrary.DerivedPath
     , System.Nix.Arbitrary.Hash
     , System.Nix.Arbitrary.OutputName
+    , System.Nix.Arbitrary.Realisation
     , System.Nix.Arbitrary.Signature
     , System.Nix.Arbitrary.Store.Types
     , System.Nix.Arbitrary.StorePath

hnix-store-tests/src/System/Nix/Arbitrary.hs

@@ -12,6 +12,7 @@ import System.Nix.Arbitrary.Derivation ()
 import System.Nix.Arbitrary.DerivedPath ()
 import System.Nix.Arbitrary.Hash ()
 import System.Nix.Arbitrary.OutputName ()
+import System.Nix.Arbitrary.Realisation ()
 import System.Nix.Arbitrary.Signature ()
 import System.Nix.Arbitrary.Store.Types ()
 import System.Nix.Arbitrary.StorePath ()

hnix-store-tests/src/System/Nix/Arbitrary/Realisation.hs

@@ -0,0 +1,25 @@
+-- due to recent generic-arbitrary
+{-# OPTIONS_GHC -fconstraint-solver-iterations=0 #-}
+{-# OPTIONS_GHC -Wno-orphans #-}
+module System.Nix.Arbitrary.Realisation where
+
+import System.Nix.Arbitrary.Hash ()
+import System.Nix.Arbitrary.OutputName ()
+import System.Nix.Arbitrary.Signature ()
+import System.Nix.Arbitrary.StorePath ()
+import System.Nix.Realisation (DerivationOutput, Realisation)
+
+import Test.QuickCheck (Arbitrary(..))
+import Test.QuickCheck.Arbitrary.Generic (Arg, GenericArbitrary(..), genericArbitrary, genericShrink)
+
+instance
+  ( Arg (DerivationOutput outputName) outputName
+  , Arbitrary outputName
+  ) =>
+  Arbitrary (DerivationOutput outputName)
+  where
+    arbitrary = genericArbitrary
+    shrink = genericShrink
+
+deriving via GenericArbitrary Realisation
+  instance Arbitrary Realisation