Merge pull request #104 from nmattia/nm-update-nixpkgs

nixpkgs: 18.09 -> 19.03

nix/sources.json

@@ -1,13 +1,14 @@
 {
     "nixpkgs": {
-        "url": "https://github.com/NixOS/nixpkgs-channels/archive/cb1d0c44e99f174fe415040c4566017f83010546.tar.gz",
+        "url": "https://github.com/NixOS/nixpkgs-channels/archive/8634c3b619909db7fc747faf8c03592986626e21.tar.gz",
         "owner": "NixOS",
-        "branch": "nixos-18.09",
+        "branch": "nixos-19.03",
         "url_template": "https://github.com/<owner>/<repo>/archive/<rev>.tar.gz",
         "repo": "nixpkgs-channels",
-        "sha256": "1kb3glpr08bpifpvc1fqqanqm35gwc1maclvpfdd9dywmdgaf9di",
+        "type": "tarball",
+        "sha256": "0hcpy4q64vbqmlmnfcavfxilyygyzpwdsss8g3p73ikpic0j6ziq",
         "description": "Nixpkgs/NixOS branches that track the Nixpkgs/NixOS channels",
-        "rev": "cb1d0c44e99f174fe415040c4566017f83010546"
+        "rev": "8634c3b619909db7fc747faf8c03592986626e21"
     },
     "gitignore": {
         "url": "https://github.com/hercules-ci/gitignore/archive/4064e436313191f11969986e66b81cb6bb61bae6.tar.gz",
@@ -19,4 +20,4 @@
         "description": "Nix source function for gitignore that just works",
         "rev": "4064e436313191f11969986e66b81cb6bb61bae6"
     }
-}
+}

src/Niv/GitHub.hs

@@ -15,6 +15,7 @@ import Data.String.QQ (s)
 import GHC.Exts (toList)
 import Niv.Update
 import Data.Text.Encoding (encodeUtf8)
+import qualified Data.Aeson as Aeson
 import qualified Data.Text as T
 import qualified GitHub as GH
 import qualified GitHub.Data.Name as GH
@@ -26,7 +27,8 @@ data GithubRepo = GithubRepo
   , repoDefaultBranch :: Maybe T.Text
   }
 
-executeRequest :: GH.Request 'GH.RO a -> IO (Either GH.Error a)
+executeRequest
+  :: Aeson.FromJSON a => GH.Request 'GH.RO a -> IO (Either GH.Error a)
 executeRequest req = do
   token <- fmap (GH.OAuth . encodeUtf8 . T.pack) <$> lookupEnv "GITHUB_TOKEN"
   GH.executeRequestMaybe token req