From 17fe4f88a86e416e80d85a4dad2dacf21feeccde Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Pacana?= <pawel.pacana@gmail.com>
Date: Wed, 24 Jun 2026 22:21:29 +0200
Subject: [PATCH] Use treefmt to drive all formatters

- Replace the per-tool format invocations with treefmt (devenv's
  treefmt-nix integration): Ruby via syntax_tree, SQL via sqlfluff,
  configured in devenv.nix.
- Exclude sqlfluff's LT05 (line too long) so `sqlfluff format` exits
  0 as a formatter; the long lines it can't wrap no longer fail it.
- Point app:format and the Claude on-save hook at treefmt (SQL now
  formats on save too), drop the Rakefile format task, and update
  AGENTS.md.
---
 .sqlfluff   |  4 ++++
 AGENTS.md   |  2 +-
 Rakefile    |  5 -----
 devenv.lock | 23 ++++++++++++++++++++++-
 devenv.nix  | 26 ++++++++++++++++++++++----
 devenv.yaml |  9 +++++++--
 6 files changed, 56 insertions(+), 13 deletions(-)

diff --git a/.sqlfluff b/.sqlfluff
index 7fb4ec3..391f553 100644
--- a/.sqlfluff
+++ b/.sqlfluff
@@ -1,2 +1,6 @@
 [sqlfluff]
 dialect = postgres
+# LT05 (line too long) is unfixable for long function signatures and seed
+# rows, which makes `sqlfluff format` exit non-zero. Exclude it so it acts
+# purely as a formatter under treefmt.
+exclude_rules = LT05
diff --git a/AGENTS.md b/AGENTS.md
index 6495684..4cc278e 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -1,5 +1,5 @@
 # Agent rules
 
 - Prefer inlining variables when they are not reused.
-- After editing files, run `bin/rake format`.
+- After editing files, run `treefmt`.
 - When adding and building a feature, follow the TDD process.
diff --git a/Rakefile b/Rakefile
index 9e39bb4..eead8d7 100644
--- a/Rakefile
+++ b/Rakefile
@@ -6,11 +6,6 @@ require_relative "lib/en57/tasks"
 
 Minitest::TestTask.create
 
-task :format do
-  system("stree write **/*.rb")
-  system("sqlfluff format db")
-end
-
 task :mutate do
   system("bin/mutant run")
 end
diff --git a/devenv.lock b/devenv.lock
index 867955b..66f8095 100644
--- a/devenv.lock
+++ b/devenv.lock
@@ -173,7 +173,8 @@
         "devenv": "devenv",
         "git-hooks": "git-hooks",
         "nixpkgs": "nixpkgs",
-        "nixpkgs-ruby": "nixpkgs-ruby"
+        "nixpkgs-ruby": "nixpkgs-ruby",
+        "treefmt-nix": "treefmt-nix"
       }
     },
     "systems": {
@@ -190,6 +191,26 @@
         "repo": "default",
         "type": "github"
       }
+    },
+    "treefmt-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1780220602,
+        "narHash": "sha256-eynAfOmbmxJnkp7YewvCEbShNnnYJ9gLLqkzsYtBPeM=",
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "rev": "db947814a175b7ca6ded66e21383d938df01c227",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "type": "github"
+      }
     }
   },
   "root": "root",
diff --git a/devenv.nix b/devenv.nix
index ed8ea7e..ed18882 100644
--- a/devenv.nix
+++ b/devenv.nix
@@ -18,12 +18,30 @@
   '';
 
   tasks = {
-    "app:format".exec = "bin/rake format";
+    "app:format".exec = "treefmt";
     "app:test".exec = "bin/rake test";
     "app:mutate".exec = "bin/mutant run";
     "app:check".exec = "bin/rake"; # default: test + mutate_since
   };
 
+  # treefmt drives all formatters (Ruby via syntax_tree, SQL via sqlfluff).
+  treefmt.enable = true;
+  treefmt.config = {
+    projectRootFile = "devenv.nix";
+    settings.formatter = {
+      ruby = {
+        command = "stree";
+        options = [ "write" ];
+        includes = [ "*.rb" ];
+      };
+      sql = {
+        command = "sqlfluff";
+        options = [ "format" ];
+        includes = [ "db/**/*.sql" ];
+      };
+    };
+  };
+
   # Self-contained pg_regress run: spin up an ephemeral PostgreSQL with the
   # Nix server binaries, load the schema, run the regression schedule, then
   # tear it down. No Rakefile task, no gem, no env-var paths.
@@ -81,12 +99,12 @@
 
   claude.code.enable = true;
   claude.code.hooks.git-hooks-run.enable = false;
-  claude.code.hooks.format-ruby = {
-    name = "Format Ruby with syntax_tree";
+  claude.code.hooks.format = {
+    name = "Format edited files with treefmt";
     hookType = "PostToolUse";
     matcher = "Write|Edit";
     command = ''
-      jq -r '.tool_response.filePath // .tool_input.file_path' | { read -r f; case "$f" in *.rb) bin/stree write "$f" ;; esac; } 2>/dev/null || true
+      jq -r '.tool_response.filePath // .tool_input.file_path' | { read -r f; treefmt "$f"; } 2>/dev/null || true
     '';
   };
 }
diff --git a/devenv.yaml b/devenv.yaml
index 5a3d24b..fa85261 100644
--- a/devenv.yaml
+++ b/devenv.yaml
@@ -1,13 +1,18 @@
 inputs:
-  nixpkgs:
-    url: github:cachix/devenv-nixpkgs/rolling
   git-hooks:
     url: github:cachix/git-hooks.nix
     inputs:
       nixpkgs:
         follows: nixpkgs
+  nixpkgs:
+    url: github:cachix/devenv-nixpkgs/rolling
   nixpkgs-ruby:
     url: github:bobvanderlinden/nixpkgs-ruby
     inputs:
       nixpkgs:
         follows: nixpkgs
+  treefmt-nix:
+    url: github:numtide/treefmt-nix
+    inputs:
+      nixpkgs:
+        follows: nixpkgs
-- 
2.51.2