haskellPackages.password: use crypton, disable scrypt on non-x86

- crypton is maintained, contrary to cryptonite
- since the Hackage scrypt package uses SSE2, we can't build it on
  non-x86 platforms (non x86_64 even probably). The best option
  is to disable the Scrypt module. To prevent cabal from pulling
  in scrypt in spite of that, we need to patch build-depends to
  respect the flag.

pkgs/development/haskell-modules/configuration-hackage2nix/main.yaml

@@ -829,8 +829,6 @@ supported-platforms:
   midi-alsa:                                    [ platforms.linux ] # alsa-core only supported on linux
   midisurface:                                  [ platforms.linux ] # alsa-core only supported on linux
   OrderedBits:                                  [ platforms.x86 ] # lacks implementations for non-x86: https://github.com/choener/OrderedBits/blob/401cbbe933b1635aa33e8e9b29a4a570b0a8f044/lib/Data/Bits/Ordered.hs#L316
-  password:                                     [ platforms.x86 ] # uses scrypt, which requries x86
-  password-instances:                           [ platforms.x86 ] # uses scrypt, which requries x86
   reactivity:                                   [ platforms.windows ]
   reflex-libtelnet:                             [ platforms.linux ] # pkgs.libtelnet only supports linux
   scat:                                         [ platforms.x86 ] # uses scrypt, which requries x86

pkgs/development/haskell-modules/configuration-nix.nix

@@ -113,6 +113,35 @@ self: super: builtins.intersectAttrs super {
     '' + drv.preCheck or "";
   }) super.agda2lagda;
 
+  # - Disable scrypt support since the library used only works on x86 due to SSE2:
+  #   https://github.com/informatikr/scrypt/issues/8
+  # - Use crypton as the encryption backend. That override becomes obsolete with
+  #   3.1.* since cabal2nix picks crypton by default then.
+  password =
+    let
+      scryptSupported = pkgs.stdenv.hostPlatform.isx86;
+    in
+
+      lib.pipe
+        (super.password.override ({
+          cryptonite = self.crypton;
+        } // lib.optionalAttrs (!scryptSupported) {
+          scrypt = null;
+        }))
+        ([
+          (enableCabalFlag "crypton")
+          (disableCabalFlag "cryptonite")
+          # https://github.com/cdepillabout/password/pull/84
+          (appendPatch ./patches/password-3.0.4.0-scrypt-conditional.patch)
+          (overrideCabal (drv: {
+            # patch doesn't apply otherwise because of revisions
+            prePatch = drv.prePatch or "" + ''
+              ${pkgs.buildPackages.dos2unix}/bin/dos2unix *.cabal
+            '';
+          }))
+        ] ++ lib.optionals (!scryptSupported) [
+          (disableCabalFlag "scrypt")
+        ]);
 
   audacity = enableCabalFlag "buildExamples" (overrideCabal (drv: {
       executableHaskellDepends = [self.optparse-applicative self.soxlib];

pkgs/development/haskell-modules/patches/password-3.0.4.0-scrypt-conditional.patch

@@ -0,0 +1,21 @@
+diff --git a/password/password.cabal b/password/password.cabal
+index 506457e..8fa978b 100644
+--- a/password.cabal
++++ b/password.cabal
+@@ -186,6 +186,8 @@ test-suite password-tasty
+     other-modules:
+       Scrypt
+       Data.Password.Scrypt
++    build-depends:
++      scrypt
+   ghc-options:
+       -threaded -O2 -rtsopts -with-rtsopts=-N
+   build-depends:
+@@ -195,7 +197,6 @@ test-suite password-tasty
+     , bytestring
+     , memory
+     , quickcheck-instances
+-    , scrypt
+     , tasty
+     , tasty-hunit
+     , tasty-quickcheck