tv xmonad: add shell.nix

tv/5pkgs/haskell/xmonad-tv/shell.nix

@@ -0,0 +1,78 @@
+{ compiler ? "default" }: let
+
+  stockholm = import <stockholm>;
+
+  inherit (stockholm.systems.${lib.krops.getHostName}) config pkgs;
+  inherit (stockholm) lib;
+
+  haskellPackages =
+    if compiler == "default"
+      then pkgs.haskellPackages
+      else pkgs.haskell.packages.${compiler};
+
+  xmonadDrv = haskellPackages.callPackage (import ./.) {};
+
+in
+
+  lib.overrideDerivation xmonadDrv.env (oldAttrs: {
+    shellHook = ''
+      pkg_name=${lib.shell.escape (lib.baseNameOf (toString ./.))}
+
+      WORKDIR=${toString ./src}
+      CACHEDIR=$HOME/tmp/$pkg_name
+      HISTFILE=$CACHEDIR/bash_history
+
+      mkdir -p "$CACHEDIR"
+
+      config_XMONAD_CACHE_DIR=${lib.shell.escape
+        config.systemd.services.xmonad.environment.XMONAD_CACHE_DIR
+      }
+
+      xmonad=$CACHEDIR/main
+
+      xmonad_build() {(
+        set -efu
+        cd "$WORKDIR"
+        options=$(
+          ${pkgs.cabal-read}/bin/ghc-options "$WORKDIR/$pkg_name.cabal" xmonad
+        )
+        ghc $options \
+            -odir "$CACHEDIR" \
+            -hidir "$CACHEDIR" \
+            -o "$xmonad" \
+            main.hs
+      )}
+
+      xmonad_restart() {(
+        set -efu
+        cd "$WORKDIR"
+        if systemctl is-active xmonad; then
+          sudo systemctl stop xmonad
+          cp -b "$config_XMONAD_CACHE_DIR"/xmonad.state "$CACHEDIR"/
+          echo "xmonad.state: $(cat "$CACHEDIR"/xmonad.state)"
+        else
+          "$xmonad" --shutdown || :
+        fi
+        "$xmonad" &
+        echo xmonad pid: $! >&2
+      )}
+
+      xmonad_yield() {(
+        set -efu
+        "$xmonad" --shutdown
+        cp -b "$CACHEDIR"/xmonad.state "$config_XMONAD_CACHE_DIR"/
+        sudo systemctl start xmonad
+      )}
+
+      export PATH=${config.systemd.services.xmonad.path}:$PATH
+      export SHELL=/run/current-system/sw/bin/bash
+
+      export XMONAD_CACHE_DIR="$CACHEDIR"
+      export XMONAD_DATA_DIR="$CACHEDIR"
+      export XMONAD_CONFIG_DIR=/var/empty
+
+      unset XMONAD_STARTUP_HOOK
+
+      cd "$WORKDIR"
+    '';
+  })