fix(gs/xanthous): update xanthous.cabal, make CI catch such errors

Since xanthous has a checked-in package.yaml and cabal file, the
haskellPackages build infrastructure will use the package.yaml file for
all builds. The resulting problem is that our CI won't actually catch build
failures that would be observable with cabal or when building from the
sdist.

We fix that by filtering out the package.yaml file in pkg.nix
additionally to the filters specified in .gitignore. For this we need
gitignoreFilter from gitignore.nix which we expose as part of a functor
set from third_party.gitignoreSource to maintain interface
compatibility.

Change-Id: I337185f484d2027341f38031dcd78898706904eb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2609
Tested-by: BuildkiteCI
Reviewed-by: glittershark <grfn@gws.fyi>
Reviewed-by: tazjin <mail@tazj.in>

third_party/gitignoreSource/default.nix

@@ -1,8 +1,18 @@
 { pkgs, ... }:
 
-(import (pkgs.fetchFromGitHub {
+let
-  owner = "hercules-ci";
+  gitignoreNix = import (pkgs.fetchFromGitHub {
-  repo = "gitignore";
+    owner = "hercules-ci";
-  rev = "f9e996052b5af4032fe6150bba4a6fe4f7b9d698";
+    repo = "gitignore";
-  sha256 = "0jrh5ghisaqdd0vldbywags20m2cxpkbbk5jjjmwaw0gr8nhsafv";
+    rev = "f9e996052b5af4032fe6150bba4a6fe4f7b9d698";
-}) { inherit (pkgs) lib; }).gitignoreSource
+    sha256 = "0jrh5ghisaqdd0vldbywags20m2cxpkbbk5jjjmwaw0gr8nhsafv";
+  }) { inherit (pkgs) lib; };
+
+in {
+  __functor = _: gitignoreNix.gitignoreSource;
+
+  # expose extra functions here
+  inherit (gitignoreNix)
+    gitignoreFilter
+    ;
+}

users/glittershark/xanthous/pkg.nix

@@ -1,7 +1,16 @@
 { pkgs ? (import ../../../. {}).third_party }:
 
+let
+  ignore = pkgs.gitignoreSource.gitignoreFilter ./.;
+in
+
 import (pkgs.haskellPackages.haskellSrc2nix {
   name = "xanthous";
-  src = pkgs.gitignoreSource ./.;
+  src = builtins.path {
+    name = "xanthous-source";
+    path = ./.;
+    filter = path: type: ignore path type
+      || builtins.baseNameOf path == "package.yaml";
+  };
   extraCabal2nixOptions = "--hpack";
 })

users/glittershark/xanthous/xanthous.cabal

@@ -1,10 +1,10 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.33.1.
+-- This file has been generated from package.yaml by hpack version 0.34.4.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: bb0a26ab512a1b8d095f3fa71370dcc5221c3f20888042a0d5c41d054dc403cf
+-- hash: b46f24dcf24decf8e16be6f62943648aaafc9272d923945f97d5c26a370ad235
 
 name:           xanthous
 version:        0.1.0.0
@@ -87,7 +87,33 @@ library
       Paths_xanthous
   hs-source-dirs:
       src
-  default-extensions: BlockArguments ConstraintKinds DataKinds DeriveAnyClass DeriveGeneric DerivingStrategies DerivingVia FlexibleContexts FlexibleInstances FunctionalDependencies GADTSyntax GeneralizedNewtypeDeriving KindSignatures LambdaCase MultiWayIf NoImplicitPrelude NoStarIsType OverloadedStrings PolyKinds RankNTypes ScopedTypeVariables TupleSections TypeApplications TypeFamilies TypeOperators ViewPatterns
+  default-extensions:
+      BlockArguments
+      ConstraintKinds
+      DataKinds
+      DeriveAnyClass
+      DeriveGeneric
+      DerivingStrategies
+      DerivingVia
+      FlexibleContexts
+      FlexibleInstances
+      FunctionalDependencies
+      GADTSyntax
+      GeneralizedNewtypeDeriving
+      KindSignatures
+      LambdaCase
+      MultiWayIf
+      NoImplicitPrelude
+      NoStarIsType
+      OverloadedStrings
+      PolyKinds
+      RankNTypes
+      ScopedTypeVariables
+      TupleSections
+      TypeApplications
+      TypeFamilies
+      TypeOperators
+      ViewPatterns
   ghc-options: -Wall
   build-depends:
       JuicyPixels
@@ -140,6 +166,7 @@ library
     , raw-strings-qq
     , reflection
     , semigroupoids
+    , splitmix
     , stache
     , streams
     , text
@@ -213,7 +240,33 @@ executable xanthous
       Paths_xanthous
   hs-source-dirs:
       src
-  default-extensions: BlockArguments ConstraintKinds DataKinds DeriveAnyClass DeriveGeneric DerivingStrategies DerivingVia FlexibleContexts FlexibleInstances FunctionalDependencies GADTSyntax GeneralizedNewtypeDeriving KindSignatures LambdaCase MultiWayIf NoImplicitPrelude NoStarIsType OverloadedStrings PolyKinds RankNTypes ScopedTypeVariables TupleSections TypeApplications TypeFamilies TypeOperators ViewPatterns
+  default-extensions:
+      BlockArguments
+      ConstraintKinds
+      DataKinds
+      DeriveAnyClass
+      DeriveGeneric
+      DerivingStrategies
+      DerivingVia
+      FlexibleContexts
+      FlexibleInstances
+      FunctionalDependencies
+      GADTSyntax
+      GeneralizedNewtypeDeriving
+      KindSignatures
+      LambdaCase
+      MultiWayIf
+      NoImplicitPrelude
+      NoStarIsType
+      OverloadedStrings
+      PolyKinds
+      RankNTypes
+      ScopedTypeVariables
+      TupleSections
+      TypeApplications
+      TypeFamilies
+      TypeOperators
+      ViewPatterns
   ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N -O2
   build-depends:
       JuicyPixels
@@ -266,6 +319,7 @@ executable xanthous
     , raw-strings-qq
     , reflection
     , semigroupoids
+    , splitmix
     , stache
     , streams
     , text
@@ -306,7 +360,33 @@ test-suite test
       Paths_xanthous
   hs-source-dirs:
       test
-  default-extensions: BlockArguments ConstraintKinds DataKinds DeriveAnyClass DeriveGeneric DerivingStrategies DerivingVia FlexibleContexts FlexibleInstances FunctionalDependencies GADTSyntax GeneralizedNewtypeDeriving KindSignatures LambdaCase MultiWayIf NoImplicitPrelude NoStarIsType OverloadedStrings PolyKinds RankNTypes ScopedTypeVariables TupleSections TypeApplications TypeFamilies TypeOperators ViewPatterns
+  default-extensions:
+      BlockArguments
+      ConstraintKinds
+      DataKinds
+      DeriveAnyClass
+      DeriveGeneric
+      DerivingStrategies
+      DerivingVia
+      FlexibleContexts
+      FlexibleInstances
+      FunctionalDependencies
+      GADTSyntax
+      GeneralizedNewtypeDeriving
+      KindSignatures
+      LambdaCase
+      MultiWayIf
+      NoImplicitPrelude
+      NoStarIsType
+      OverloadedStrings
+      PolyKinds
+      RankNTypes
+      ScopedTypeVariables
+      TupleSections
+      TypeApplications
+      TypeFamilies
+      TypeOperators
+      ViewPatterns
   ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N -O0
   build-depends:
       JuicyPixels
@@ -360,6 +440,7 @@ test-suite test
     , raw-strings-qq
     , reflection
     , semigroupoids
+    , splitmix
     , stache
     , streams
     , tasty
@@ -387,7 +468,33 @@ benchmark benchmark
       Paths_xanthous
   hs-source-dirs:
       bench
-  default-extensions: BlockArguments ConstraintKinds DataKinds DeriveAnyClass DeriveGeneric DerivingStrategies DerivingVia FlexibleContexts FlexibleInstances FunctionalDependencies GADTSyntax GeneralizedNewtypeDeriving KindSignatures LambdaCase MultiWayIf NoImplicitPrelude NoStarIsType OverloadedStrings PolyKinds RankNTypes ScopedTypeVariables TupleSections TypeApplications TypeFamilies TypeOperators ViewPatterns
+  default-extensions:
+      BlockArguments
+      ConstraintKinds
+      DataKinds
+      DeriveAnyClass
+      DeriveGeneric
+      DerivingStrategies
+      DerivingVia
+      FlexibleContexts
+      FlexibleInstances
+      FunctionalDependencies
+      GADTSyntax
+      GeneralizedNewtypeDeriving
+      KindSignatures
+      LambdaCase
+      MultiWayIf
+      NoImplicitPrelude
+      NoStarIsType
+      OverloadedStrings
+      PolyKinds
+      RankNTypes
+      ScopedTypeVariables
+      TupleSections
+      TypeApplications
+      TypeFamilies
+      TypeOperators
+      ViewPatterns
   ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N
   build-depends:
       JuicyPixels
@@ -440,6 +547,7 @@ benchmark benchmark
     , raw-strings-qq
     , reflection
     , semigroupoids
+    , splitmix
     , stache
     , streams
     , text