pkgs.haskell.package-list: init

This commit introduces a maintainer script to upload our current list of
haskell-packages to hackage.

maintainers/scripts/haskell/upload-nixos-package-list-to-hackage.sh

@@ -0,0 +1,21 @@
+#! /usr/bin/env nix-shell
+#! nix-shell -i bash -p nix curl gnused -I nixpkgs=.
+
+# On Hackage every package description shows a category "Distributions" which
+# lists a "NixOS" version.
+# This script uploads a csv to hackage which will update the displayed versions
+# based on the current versions in nixpkgs.  This happens with on simple http
+# request.
+
+# For authorization you just need to have any valid hackage account. This
+# script uses the `username` and `password-command` field from your
+# ~/.cabal/config file.
+
+# e.g. username: maralorn
+#      password-command: pass hackage.haskell.org (this can be any command, but not an arbitrary shell expression.)
+# Those fields are specified under `upload` on the `cabal` man page.
+
+package_list="$(nix-build -A haskell.package-list)/nixos-hackage-packages.csv"
+username=$(grep "^username:" ~/.cabal/config | sed "s/^username: //")
+password_command=$(grep "^password-command:" ~/.cabal/config | sed "s/^password-command: //")
+curl -u "$username:$($password_command)" --digest -H "Content-type: text/csv" -T "$package_list" http://hackage.haskell.org/distro/NixOS/packages.csv

pkgs/development/haskell-modules/HACKING.md

@@ -241,6 +241,14 @@ When you've double-checked these points, go ahead and merge the `haskell-updates
 After merging, **make sure not to delete the `haskell-updates` branch**, since it
 causes all currently open Haskell-related pull-requests to be automatically closed on GitHub.
 
+## Update Hackage Version Information
+
+After merging into master you can update what hackage displays as the current
+version in NixOS for every individual package.
+To do this you run `maintainers/scripts/haskell/upload-nixos-package-list-to-hackage.sh`.
+See the script for how to provide credentials. Once you have configured that
+running this takes only a few seconds.
+
 ## Additional Info
 
 Here are some additional tips that didn't fit in above.

pkgs/development/haskell-modules/package-list.nix

@@ -0,0 +1,19 @@
+{ runCommand, haskellPackages, lib, all-cabal-hashes, writeShellScript }:
+let
+  pkgLine = name: pkg:
+    let
+      version = pkg.version or "";
+    in
+    if version != "" then
+      ''"${name}","${version}","http://hydra.nixos.org/job/nixpkgs/trunk/haskellPackages.${name}.x86_64-linux"''
+    else "";
+  all-haskellPackages = builtins.toFile "all-haskellPackages" (lib.concatStringsSep "\n" (lib.filter (x: x != "") (lib.mapAttrsToList pkgLine haskellPackages)));
+in
+runCommand "hackage-package-list" { }
+  # This command will make a join between all packages on hackage and haskellPackages.*.
+  # It creates a valid csv file which can be uploaded to hackage.haskell.org.
+  # The call is wrapped in echo $(...) to trim trailing newline, which hackage requires.
+  ''
+    mkdir -p $out/bin
+    echo -n "$(tar -t -f ${all-cabal-hashes} | sed 's![^/]*/\([^/]*\)/.*!"\1"!' | sort -u | join -t , - ${all-haskellPackages})" > $out/nixos-hackage-packages.csv
+  ''

pkgs/top-level/haskell-packages.nix

@@ -42,6 +42,8 @@ let
 in {
   lib = haskellLib;
 
+  package-list = callPackage ../development/haskell-modules/package-list.nix {};
+
   compiler = {
 
     ghc865Binary = callPackage ../development/compilers/ghc/8.6.5-binary.nix { };