From 388d1056e8adf19453993029b8569c0b00a74a07 Mon Sep 17 00:00:00 2001
From: ncaq <ncaq@ncaq.net>
Date: Thu, 10 Jul 2025 14:44:29 +0900
Subject: [PATCH 1/3] fix(cabal): cabal-fmt and cabal-gild discover module

`cabal-fmt` and `cabal-gild` can discover module and autocomplete.
```cabal
-- cabal-gild: discover ./src
exposed-modules:
```
The current system, treefmt can't detect change haskell module.
I write to depend to haskell module file.
---
 examples/formatter-cabal-fmt.toml  | 19 ++++++++--
 examples/formatter-cabal-gild.toml | 17 ++++++++-
 programs/cabal-fmt.nix             | 57 ++++++++++++++++++++++++++++--
 programs/cabal-gild.nix            | 25 +++++++++++--
 4 files changed, 110 insertions(+), 8 deletions(-)

diff --git a/examples/formatter-cabal-fmt.toml b/examples/formatter-cabal-fmt.toml
index de69588..9975aa4 100644
--- a/examples/formatter-cabal-fmt.toml
+++ b/examples/formatter-cabal-fmt.toml
@@ -1,6 +1,19 @@
 # Example generated by ../examples.sh
 [formatter.cabal-fmt]
-command = "cabal-fmt"
+command = "cabal-fmt-wrapper"
 excludes = []
-includes = ["*.cabal"]
-options = ["--inplace"]
+includes = [
+    "*.cabal",
+    "*.chs",
+    "*.cpphs",
+    "*.gc",
+    "*.hs",
+    "*.hsc",
+    "*.hsig",
+    "*.lhs",
+    "*.lhsig",
+    "*.ly",
+    "*.x",
+    "*.y",
+]
+options = []
diff --git a/examples/formatter-cabal-gild.toml b/examples/formatter-cabal-gild.toml
index 382cdc0..bd6f1a3 100644
--- a/examples/formatter-cabal-gild.toml
+++ b/examples/formatter-cabal-gild.toml
@@ -2,5 +2,20 @@
 [formatter.cabal-gild]
 command = "cabal-gild-wrapper"
 excludes = []
-includes = ["*.cabal", "cabal.project", "cabal.project.local"]
+includes = [
+    "*.cabal",
+    "cabal.project",
+    "cabal.project.local",
+    "*.chs",
+    "*.cpphs",
+    "*.gc",
+    "*.hs",
+    "*.hsc",
+    "*.hsig",
+    "*.lhs",
+    "*.lhsig",
+    "*.ly",
+    "*.x",
+    "*.y",
+]
 options = []
diff --git a/programs/cabal-fmt.nix b/programs/cabal-fmt.nix
index f72895d..c19428c 100644
--- a/programs/cabal-fmt.nix
+++ b/programs/cabal-fmt.nix
@@ -1,4 +1,13 @@
-{ mkFormatterModule, ... }:
+{
+  lib,
+  config,
+  pkgs,
+  mkFormatterModule,
+  ...
+}:
+let
+  cfg = config.programs.cabal-fmt;
+in
 {
   meta.maintainers = [ ];
 
@@ -10,7 +19,51 @@
         "cabal-fmt"
       ];
       args = [ "--inplace" ];
-      includes = [ "*.cabal" ];
+      includes = [
+        "*.cabal"
+        # Include Haskell source files to detect changes
+        # for cabal-fmt's module discovery feature
+        "*.chs"
+        "*.cpphs"
+        "*.gc"
+        "*.hs"
+        "*.hsc"
+        "*.hsig"
+        "*.lhs"
+        "*.lhsig"
+        "*.ly"
+        "*.x"
+        "*.y"
+      ];
     })
   ];
+
+  config = lib.mkIf cfg.enable {
+    settings.formatter.cabal-fmt = {
+      # Override command to filter out non-cabal files
+      command = pkgs.writeShellApplication {
+        name = "cabal-fmt-wrapper";
+        text = ''
+          cabal_files=()
+          for file in "$@"; do
+            # Only process .cabal files
+            case "$file" in
+              *.cabal)
+                cabal_files+=("$file")
+                ;;
+              *)
+                # Skip non-cabal files (e.g., .hs files)
+                ;;
+            esac
+          done
+
+          if [ ''${#cabal_files[@]} -gt 0 ]; then
+            ${lib.getExe cfg.package} --inplace "''${cabal_files[@]}"
+          fi
+        '';
+      };
+      # Clear args since we're handling them in the wrapper
+      options = lib.mkForce [ ];
+    };
+  };
 }
diff --git a/programs/cabal-gild.nix b/programs/cabal-gild.nix
index 8bf94ac..47b0b8d 100644
--- a/programs/cabal-gild.nix
+++ b/programs/cabal-gild.nix
@@ -1,8 +1,8 @@
 {
-  mkFormatterModule,
   lib,
   config,
   pkgs,
+  mkFormatterModule,
   ...
 }:
 
@@ -23,6 +23,19 @@ in
         "*.cabal"
         "cabal.project"
         "cabal.project.local"
+        # Include Haskell source files to detect changes
+        # for cabal-gild's module discovery feature
+        "*.chs"
+        "*.cpphs"
+        "*.gc"
+        "*.hs"
+        "*.hsc"
+        "*.hsig"
+        "*.lhs"
+        "*.lhsig"
+        "*.ly"
+        "*.x"
+        "*.y"
       ];
     })
   ];
@@ -35,7 +48,15 @@ in
         name = "cabal-gild-wrapper";
         text = ''
           for file in "$@"; do
-            ${lib.getExe cfg.package} --io="$file"
+            # Only process .cabal files and cabal.project files
+            case "$file" in
+              *.cabal|cabal.project|cabal.project.local)
+                ${lib.getExe cfg.package} --io="$file"
+                ;;
+              *)
+                # Skip non-cabal files (e.g., .hs files)
+                ;;
+            esac
           done
         '';
       };

From dc6e962f92804623a292f5f1444033e2ba780476 Mon Sep 17 00:00:00 2001
From: ncaq <ncaq@ncaq.net>
Date: Tue, 16 Sep 2025 15:00:50 +0900
Subject: [PATCH 2/3] fix(cabal-fmt): remove `--inplace` argument

To use manual script.
---
 programs/cabal-fmt.nix | 1 -
 1 file changed, 1 deletion(-)

diff --git a/programs/cabal-fmt.nix b/programs/cabal-fmt.nix
index c19428c..c6c5175 100644
--- a/programs/cabal-fmt.nix
+++ b/programs/cabal-fmt.nix
@@ -18,7 +18,6 @@ in
         "haskellPackages"
         "cabal-fmt"
       ];
-      args = [ "--inplace" ];
       includes = [
         "*.cabal"
         # Include Haskell source files to detect changes

From 52166107b42160b6c29d5472e7d6bc12497b93e4 Mon Sep 17 00:00:00 2001
From: ncaq <ncaq@ncaq.net>
Date: Tue, 16 Sep 2025 14:57:19 +0900
Subject: [PATCH 3/3] fix(nix): simplify cabal wrappers to execute
 speculatively

- Drop file filtering loops in cabal-fmt.nix and cabal-gild.nix
- Use git ls-files -z | xargs to run formatter on all .cabal files
- Avoid strict detection of cabal file args to simplify wrapper logic
---
 programs/cabal-fmt.nix  | 23 +++++------------------
 programs/cabal-gild.nix | 18 +++++-------------
 2 files changed, 10 insertions(+), 31 deletions(-)

diff --git a/programs/cabal-fmt.nix b/programs/cabal-fmt.nix
index c6c5175..979fc86 100644
--- a/programs/cabal-fmt.nix
+++ b/programs/cabal-fmt.nix
@@ -42,24 +42,11 @@ in
       # Override command to filter out non-cabal files
       command = pkgs.writeShellApplication {
         name = "cabal-fmt-wrapper";
-        text = ''
-          cabal_files=()
-          for file in "$@"; do
-            # Only process .cabal files
-            case "$file" in
-              *.cabal)
-                cabal_files+=("$file")
-                ;;
-              *)
-                # Skip non-cabal files (e.g., .hs files)
-                ;;
-            esac
-          done
-
-          if [ ''${#cabal_files[@]} -gt 0 ]; then
-            ${lib.getExe cfg.package} --inplace "''${cabal_files[@]}"
-          fi
-        '';
+        # The cabal file needs to be formatted by a formatter along with other Haskell source code.
+        # For example, module completion by `cabal-fmt: discover`.
+        # It is difficult to determine this strictly.
+        # Since formatting with cabal-fmt doesn't take much time, we execute it speculatively.
+        text = ''${pkgs.git}/bin/git ls-files -z "*.cabal"|${pkgs.parallel}/bin/parallel --null "${lib.getExe cfg.package} --inplace {}"'';
       };
       # Clear args since we're handling them in the wrapper
       options = lib.mkForce [ ];
diff --git a/programs/cabal-gild.nix b/programs/cabal-gild.nix
index 47b0b8d..81583b6 100644
--- a/programs/cabal-gild.nix
+++ b/programs/cabal-gild.nix
@@ -46,19 +46,11 @@ in
       # https://github.com/tfausak/cabal-gild/issues/35
       command = pkgs.writeShellApplication {
         name = "cabal-gild-wrapper";
-        text = ''
-          for file in "$@"; do
-            # Only process .cabal files and cabal.project files
-            case "$file" in
-              *.cabal|cabal.project|cabal.project.local)
-                ${lib.getExe cfg.package} --io="$file"
-                ;;
-              *)
-                # Skip non-cabal files (e.g., .hs files)
-                ;;
-            esac
-          done
-        '';
+        # The cabal file needs to be formatted by a formatter along with other Haskell source code.
+        # For example, module completion by `cabal-gild: discover`.
+        # It is difficult to determine this strictly.
+        # Since formatting with cabal-gild doesn't take much time, we execute it speculatively.
+        text = ''${pkgs.git}/bin/git ls-files -z "*.cabal"|${pkgs.parallel}/bin/parallel --null "${lib.getExe cfg.package} --io {}"'';
       };
     };
   };