install zeal docs for packages like mx-sanebot

hosts/by-name/lappy/default.nix

@@ -19,6 +19,7 @@
     "desktopGuiApps"
     "stepmania"
   ];
+  sane.programs.mx-sanebot.enableFor.system = true;  # for the docs
 
   sops.secrets.colin-passwd = {
     sopsFile = ../../../secrets/lappy.yaml;

hosts/common/programs/default.nix

@@ -242,6 +242,7 @@ let
   # packages not part of any package set
   otherPkgs = {
     inherit (pkgs)
+      mx-sanebot
       stepmania
     ;
   };
@@ -270,6 +271,7 @@ in
     ./sublime-music.nix
     ./vlc.nix
     ./web-browser.nix
+    ./zeal.nix
     ./zsh
   ];
 
@@ -403,11 +405,6 @@ in
 
         yarn.persist.plaintext = [ ".cache/yarn" ];
 
-        zeal-qt5.persist.plaintext = [
-          ".cache/Zeal"
-          ".local/share/Zeal"
-        ];
-
         # zcash coins. safe to delete, just slow to regenerate (10-60 minutes)
         zecwallet-lite.persist.private = [ ".zcash" ];
       }

hosts/common/programs/zeal.nix

@@ -0,0 +1,16 @@
+{ config, lib, sane-lib, ... }:
+let
+  inherit (lib) mkIf;
+in {
+  sane.programs.zeal-qt5 = {
+    persist.plaintext = [
+      ".cache/Zeal"
+      ".local/share/Zeal"
+    ];
+    fs.".local/share/Zeal/Zeal/system" = sane-lib.fs.wantedSymlinkTo "/run/current-system/sw/share/docset";
+  };
+
+  environment.pathsToLink = mkIf config.sane.programs.zeal-qt5.enabled [
+    "/share/docset"
+  ];
+}

pkgs/mx-sanebot/default.nix

@@ -14,9 +14,14 @@ rustPlatform.buildRustPackage {
   nativeBuildInputs = [ pkg-config ] ++ lib.optional (cargo-docset != null) cargo-docset;
   buildInputs = [ openssl ];
 
-  # to build dash/zeal docs:
-  # `cargo-docset`
-  # `cp -r -rcp target/docset/mx-sanebot.docset ~/.local/share/Zeal/Zeal/docsets/`
+  postBuild = ''
+    cargo-docset docset
+  '';
+
+  postInstall = ''
+    mkdir -p $out/share/docset
+    cp -R target/docset/* $out/share/docset/
+  '';
 
   # enables debug builds, if we want: https://github.com/NixOS/nixpkgs/issues/60919.
   hardeningDisable = [ "fortify" ];