From 5f5462dd3013d983cc9c34d0359d24eed432a0f2 Mon Sep 17 00:00:00 2001
From: nvmd <kazenyuk@pm.me>
Date: Wed, 20 Sep 2023 20:07:45 +0300
Subject: [PATCH] Add back withHoogle support (#1823)

* Add hoogle support in flake-parts module

* Update withHoogle documentation
---
 Guide/editors.markdown | 56 ++++++++++++++++++++++--------------------
 flake-module.nix       | 12 ++++++++-
 2 files changed, 41 insertions(+), 27 deletions(-)

diff --git a/Guide/editors.markdown b/Guide/editors.markdown
index 992ca8764..26f78b3c4 100644
--- a/Guide/editors.markdown
+++ b/Guide/editors.markdown
@@ -214,34 +214,38 @@ To quickly look up function type signatures you can use the built-in hoogle serv
 
 To install it:
 
-1. Open `default.nix`
-2. Add `withHoogle = true;` to the `haskellEnv` block, like this:
+1. Open `flake.nix`
+2. Add `withHoogle = true;` to the `ihp` project block, inside `perSystem` function invocation like this:
 
 ```nix
-let
-    ihp = builtins.fetchGit {
-        url = "https://github.com/digitallyinduced/ihp.git";
-        ref = "refs/tags/v0.14.0";
-    };
-    haskellEnv = import "${ihp}/NixSupport/default.nix" {
-        ihp = ihp;
-        haskellDeps = p: with p; [
-            cabal-install
-            base
-            wai
-            text
-            hlint
-            p.ihp
-        ];
-        otherDeps = p: with p; [
-            # Native dependencies, e.g. imagemagick
-        ];
-        projectPath = ./.;
-
-        withHoogle = true; # <-------
+...
+outputs = inputs@{ ihp, flake-parts, systems, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+
+        systems = import systems;
+        imports = [ ihp.flakeModules.default ];
+
+        perSystem = { pkgs, ... }: {
+            ihp = {
+                enable = true;
+                projectPath = ./.;
+                packages = with pkgs; [
+                    # Native dependencies, e.g. imagemagick
+                ];
+                haskellPackages = p: with p; [
+                    # Haskell dependencies go here
+                    p.ihp
+                    cabal-install
+                    base
+                    wai
+                    text
+                    hlint
+                ];
+                withHoogle = true; # <-------
+            };
+        };
+
     };
-in
-    haskellEnv
 ```
 
 Run `devenv up` to remake your dev environment.
@@ -249,5 +253,5 @@ Run `devenv up` to remake your dev environment.
 After that you can use the following command to start hoogle at `localhost:8080`:
 
 ```bash
-nix-shell --run 'hoogle server --local -p 8080'
+hoogle server --local -p 8080
 ```
diff --git a/flake-module.nix b/flake-module.nix
index 50a14e208..5cdd568e5 100644
--- a/flake-module.nix
+++ b/flake-module.nix
@@ -59,6 +59,14 @@ ihpFlake:
                     type = lib.types.path;
                 };
 
+                withHoogle = lib.mkOption {
+                    description = ''
+                        Enable Hoogle support. Adds `hoogle` command to PATH.
+                    '';
+                    type = lib.types.bool;
+                    default = false;
+                };
+
                 dontCheckPackages = lib.mkOption {
                     description = ''
                         List of Haskell package names whose tests are skipped during build.
@@ -166,7 +174,9 @@ ihpFlake:
                 containers = lib.mkForce {};
 
                 languages.haskell.enable = true;
-                languages.haskell.package = ghcCompiler.ghc.withPackages cfg.haskellPackages;
+                languages.haskell.package = (if cfg.withHoogle
+                                             then ghcCompiler.ghc.withHoogle
+                                             else ghcCompiler.ghc.withPackages) cfg.haskellPackages;
 
                 languages.haskell.languageServer = ghcCompiler.haskell-language-server;
                 languages.haskell.stack = null; # Stack is not used in IHP