Tidy

- Add CI specific treefmt config
- Link devshell to .direnv
- Set HLS in .vscode/config.json

Author: pwm

.envrc

@@ -1,6 +1,16 @@
 #!/usr/bin/env bash
 use nix
+
+# Watch for changes in the following files
 watch_file nixkell.toml
 watch_file package.yaml
 watch_file nix/*
 
+# Link the shell path (set in shell.nix) into .direnv
+mkdir -p "$(direnv_layout_dir)"
+rm -f "$(direnv_layout_dir)/shell"
+ln -s "$DEVSHELL_PATH" "$(direnv_layout_dir)/shell"
+
+if [[ -f .envrc.private ]]; then
+  source .envrc.private
+fi

.github/workflows/nix.yml

@@ -62,7 +62,7 @@ jobs:
         if: ${{ runner.os == 'Linux' }}
         uses: jlumbroso/free-disk-space@main
 
-      - name: Set nix path
+      - name: Set nixpkgs url
         id: nix-path
         run: |
           echo "nixpkgs=$(jq -r .nixpkgs.url ./nix/sources.json)" | tee -a $GITHUB_OUTPUT
@@ -74,7 +74,7 @@ jobs:
           extra_nix_config: |
             log-lines = 1000
 
-      - name: Install and configure Cachix
+      - name: Install and authorise Cachix
         uses: cachix/cachix-action@v15
         with:
           name: nixkell
@@ -84,10 +84,10 @@ jobs:
         run: |
           nix-shell --run "echo OK"
 
-      - name: Check code formatting (Linux only)
+      - name: Treefmt (Linux only)
         if: ${{ runner.os == 'Linux' }}
         run: |
-          nix-shell --run "treefmt --fail-on-change"
+          nix-shell --run "treefmt --ci --on-unmatched=debug --config-file treefmt-ci.toml --tree-root ."
 
       - name: GHC version
         run: |

.gitignore

@@ -1,3 +1,4 @@
+.direnv
 .ghc.environment*
 .hie
 cabal.project.local

.vscode/settings.json

@@ -1,4 +1,5 @@
 {
+  "haskell.serverExecutablePath": "haskell-language-server",
   "nix.serverPath": "nil",
   "nix.serverSettings": {
     "nil": {

nix/packages.nix

@@ -39,17 +39,31 @@ let
           "--ghc-option=-fwhole-archive-hs-libs");
     in lib.pipe pkg confFns;
 
-  hlsDisablePlugins = pkgs.lib.foldr (plugin: hls:
-    hlib.disableCabalFlag
-    (hls.override { ${"hls-" + plugin + "-plugin"} = null; }) plugin);
+  # pkgs/development/haskell-modules/configuration-hackage2nix/broken.yaml
+  unbreak = drv:
+    drv.overrideAttrs (prev: {
+      meta = prev.meta // { broken = false; };
+    });
+
+  # By default they live in ./haskellPackages/patches
+  patch = drv: patches:
+    drv.overrideAttrs (prev: {
+      patches = (prev.patches or [ ]) ++ patches;
+    });
+
+  hlsDisablePlugins =
+    pkgs.lib.foldr
+      (plugin: hls: hlib.disableCabalFlag
+        (hls.override (_: { ${plugin} = null; }))
+        plugin);
 
   # Create your own setup using the choosen GHC version (in the config) as a starting point
   ourHaskell = let
     # https://github.com/pwm/nixkell#direct-hackagegithub-dependencies
     depsFromDir = hlib.packagesFromDirectory { directory = ./packages; };
 
     manual = hfinal: hprev: {
-      cabal-install = util.patch hprev.cabal-install
+      cabal-install = patch hprev.cabal-install
         [ ./patches/prevent_missing_index_error.patch ];
 
       haskell-language-server = hlsDisablePlugins hprev.haskell-language-server

nix/util.nix

@@ -44,7 +44,4 @@
       gitIgnore path type && !builtins.elem (baseNameOf path) files
       && !lib.any (d: lib.hasPrefix d (relToPath path)) paths;
     };
-
-  patch = name: patches:
-    name.overrideAttrs (prev: { patches = prev.patches or [ ] ++ patches; });
 }

nixkell.toml

@@ -17,14 +17,14 @@ haskell_tools = [
   "cabal-install",
   "haskell-language-server",
   "hlint",
-  "nixfmt",
   "ormolu",
 ]
 
 tools = [
   "cabal2nix",
   "nil",
   "niv",
+  "nixpkgs-fmt",
   "shellcheck",
   "shfmt",
   "treefmt",

shell.nix

@@ -3,7 +3,8 @@ let pkgs = import ./nix { inherit system compiler; };
 in pkgs.mkShell {
   buildInputs = [ pkgs.nixkell.shell ];
   shellHook = ''
-    export LD_LIBRARY_PATH=${pkgs.nixkell.shell}/lib:$LD_LIBRARY_PATH
+    export DEVSHELL_PATH="${pkgs.nixkell.shell}"
+    export LD_LIBRARY_PATH="${pkgs.nixkell.shell}/lib$${LD_LIBRARY_PATH:+:$$LD_LIBRARY_PATH}"
     logo
   '';
 }

treefmt-ci.toml

@@ -0,0 +1,43 @@
+# One CLI to format the code tree - https://github.com/numtide/treefmt
+
+[formatter.haskell]
+command = "ormolu"
+includes = ["*.hs"]
+options = [
+  "--mode", "check",
+  "--check-idempotence",
+]
+
+[formatter.nix]
+command = "nixpkgs-fmt"
+includes = ["*.nix"]
+excludes = [
+  "nix/packages/*.nix",
+  "nix/sources.nix",
+]
+options = [
+  "--check",
+]
+
+[formatter.shell]
+command = "shfmt"
+includes = ["*.sh"]
+options = [
+    "--indent", "2",
+    "--simplify",
+    "--diff",
+]
+
+[formatter.prettier]
+command = "prettier"
+includes = [
+    "*.json",
+    "*.md",
+    "*.yaml",
+]
+options = [
+  "--list-different"
+]
+excludes = [
+  "nix/sources.json",
+]

treefmt.toml

@@ -2,14 +2,14 @@
 
 [formatter.haskell]
 command = "ormolu"
+includes = ["*.hs"]
 options = [
   "--mode", "inplace",
-  "--check-idempotence"
+  "--check-idempotence",
 ]
-includes = ["*.hs"]
 
 [formatter.nix]
-command = "nixfmt"
+command = "nixpkgs-fmt"
 includes = ["*.nix"]
 excludes = [
   "nix/packages/*.nix",
@@ -18,9 +18,9 @@ excludes = [
 
 [formatter.shell]
 command = "shfmt"
+includes = ["*.sh"]
 options = [
     "--indent", "2",
     "--simplify",
     "--write",
 ]
-includes = ["*.sh"]