svelte: isolate prettier formatter wiring and fix plugin runtime packaging

docs/manual/release-notes/rl-0.9.md

@@ -390,4 +390,10 @@ https://github.com/gorbit99/codewindow.nvim
 
 - Add razor support for `roslyn_ls` and `csharp_ls`
 
+[suiiii](https://github.com/suicide)
+
+- Fix `languages.svelte` formatting to use an isolated Conform formatter id and
+  a wrapped Prettier package, so enabling Svelte support no longer overrides
+  TypeScript formatting or breaks Svelte plugin resolution at runtime.
+
 <!-- vim: set textwidth=80: -->

flake/pkgs/by-name/prettier-plugin-svelte/package.nix

@@ -1,6 +1,8 @@
 {
   buildNpmPackage,
   fetchFromGitHub,
+  makeWrapper,
+  nodejs,
   pins,
 }: let
   pin = pins.prettier-plugin-svelte;
@@ -9,6 +11,8 @@ in
     pname = "prettier-plugin-svelte";
     version = pin.version or pin.revision;
 
+    meta.mainProgram = "prettier";
+
     src = fetchFromGitHub {
       inherit (pin.repository) owner repo;
       rev = finalAttrs.version;
@@ -16,4 +20,21 @@ in
     };
 
     npmDepsHash = "sha256-XVyLW0XDCvZCZxu8g1fP7fRfeU3Hz81o5FCi/i4BKQw=";
+
+    nativeBuildInputs = [makeWrapper];
+
+    installPhase = ''
+      runHook preInstall
+
+      mkdir -p "$out/bin" "$out/lib"
+      cp -r node_modules "$out/lib/"
+      mkdir -p "$out/lib/node_modules/prettier-plugin-svelte"
+      cp -r browser.js index.d.ts package.json plugin.js plugin.js.map "$out/lib/node_modules/prettier-plugin-svelte/"
+
+      makeWrapper "${nodejs}/bin/node" "$out/bin/prettier" \
+        --add-flags "$out/lib/node_modules/prettier/bin/prettier.cjs" \
+        --set NODE_PATH "$out/lib/node_modules"
+
+      runHook postInstall
+    '';
   })

modules/plugins/languages/svelte.nix

@@ -8,7 +8,7 @@
   inherit (builtins) attrNames;
   inherit (lib.options) mkEnableOption mkOption literalExpression;
   inherit (lib.modules) mkIf mkMerge;
-  inherit (lib.meta) getExe;
+  inherit (lib.meta) getExe getExe';
   inherit (lib.types) enum coercedTo;
   inherit (lib.nvim.types) mkGrammarOption diagnostics deprecatedSingleOrListOf;
   inherit (lib.nvim.attrsets) mapListToAttrs;
@@ -16,6 +16,14 @@
 
   cfg = config.vim.languages.svelte;
 
+  formatterNames = {
+    prettier = "prettier_svelte";
+    biome = "biome";
+  };
+
+  mapFormatterName = name: formatterNames.${name};
+  configuredFormatters = map mapFormatterName cfg.format.type;
+
   defaultServers = ["svelte"];
   servers = {
     svelte = {
@@ -56,13 +64,12 @@
 
   defaultFormat = ["prettier"];
   formats = let
-    prettierPlugin = inputs.self.packages.${pkgs.stdenv.system}.prettier-plugin-svelte;
-    prettierPluginPath = "${prettierPlugin}/lib/node_modules/prettier-plugin-svelte/plugin.js";
+    prettierWithSvelte = inputs.self.packages.${pkgs.stdenv.system}.prettier-plugin-svelte;
   in {
-    prettier = {
-      command = getExe pkgs.prettier;
+    prettier_svelte = {
+      command = getExe' prettierWithSvelte "prettier";
       options.ft_parsers.svelte = "svelte";
-      prepend_args = ["--plugin=${prettierPluginPath}"];
+      prepend_args = ["--plugin=${prettierWithSvelte}/lib/node_modules/prettier-plugin-svelte/plugin.js"];
     };
 
     biome = {
@@ -98,7 +105,7 @@
       lib.warn
       "vim.languages.svelte.format.type: prettierd is deprecated, use prettier instead"
       "prettier")
-    (enum (attrNames formats)));
+    (enum (attrNames formatterNames)));
 in {
   options.vim.languages.svelte = {
     enable = mkEnableOption "Svelte language support";
@@ -179,13 +186,13 @@ in {
       vim.formatter.conform-nvim = {
         enable = true;
         setupOpts = {
-          formatters_by_ft.svelte = cfg.format.type;
+          formatters_by_ft.svelte = configuredFormatters;
           formatters =
             mapListToAttrs (name: {
               inherit name;
               value = formats.${name};
             })
-            cfg.format.type;
+            configuredFormatters;
         };
       };
     })