Use GTKCssLanguageServer formatter (#860)

Author: sonnyp

.github/CODEOWNERS

@@ -1,8 +1,15 @@
 * @sonnyp
+
+/src/langs/vala/ @lw64
 *.vala @lw64
+
+/src/langs/rust/ @lw64
 *.rs @Hofer-Julian
 Cargo.toml @Hofer-Julian
 Cargo.lock @Hofer-Julian
+
+/src/langs/python/ @theCapypara
+*.py @theCapypara
+
 *.c @andyholmes
 *.h @andyholmes
-*.py @theCapypara

src/PanelStyle.js

@@ -1,9 +1,7 @@
 import Gio from "gi://Gio";
 import GObject from "gi://GObject";
 
-import { setup as setupCSS } from "./langs/css/css.js";
-
-export default function PanelStyle({ builder, document_css, settings }) {
+export default function PanelStyle({ builder, settings }) {
   const button_style = builder.get_object("button_style");
   const panel_style = builder.get_object("panel_style");
   settings.bind(
@@ -18,5 +16,4 @@ export default function PanelStyle({ builder, document_css, settings }) {
     "visible",
     GObject.BindingFlags.SYNC_CREATE,
   );
-  setupCSS({ document: document_css });
 }

src/langs/css/CssDocument.js

@@ -1,14 +1,33 @@
-import { format as prettier } from "../../lib/prettier.js";
-import prettier_postcss from "../../lib/prettier-postcss.js";
-
 import Document from "../../Document.js";
+import { applyTextEdits } from "../../lsp/sourceview.js";
+import { setup } from "./css.js";
 
 export class CssDocument extends Document {
+  constructor(...args) {
+    super(...args);
+
+    this.lspc = setup({ document: this });
+  }
+
   async format() {
-    const code = await prettier(this.buffer.text, {
-      parser: "css",
-      plugins: [prettier_postcss],
+    // https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#textDocument_formatting
+    const text_edits = await this.lspc.request("textDocument/formatting", {
+      textDocument: {
+        uri: this.file.get_uri(),
+      },
+      options: {
+        tabSize: 2,
+        insertSpaces: true,
+        trimTrailingWhitespace: true,
+        insertFinalNewline: true,
+        trimFinalNewlines: true,
+      },
     });
-    this.code_view.replaceText(code, true);
+
+    // Biome doesn't support diff - it just returns one edit
+    // we don't want to loose the cursor position so we use this
+    const state = this.code_view.saveState();
+    applyTextEdits(text_edits, this.buffer);
+    await this.code_view.restoreState(state);
   }
 }

src/langs/css/css.js

@@ -13,6 +13,8 @@ export function setup({ document }) {
     if (!code_view.buffer.get_modified()) return;
     lspc.didChange().catch(console.error);
   });
+
+  return lspc;
 }
 
 function createLSPClient({ code_view, file }) {

src/langs/css/meson.build

@@ -0,0 +1,15 @@
+gjspack = find_program(meson.project_source_root() / 'troll/gjspack/bin/gjspack')
+custom_target('prettier',
+  input: ['prettier.js'],
+  output: ['prettier', 'prettier.src.gresource'],
+  command: [
+    gjspack,
+    '--resource-root', meson.project_source_root() / 'src',
+    '@INPUT0@',
+    '@OUTDIR@',
+  ],
+  install: true,
+  install_dir: get_option('bindir'),
+  build_always_stale: true,
+)
+

src/langs/css/prettier.js

@@ -0,0 +1,29 @@
+#!/usr/bin/env -S gjs -m
+
+// Shim to Node.js prettier CLI for GTKCssLanguageServer
+// ./src/langs/css/prettier.js --stdin-filepath src/style.css
+// or
+// ./troll/gjspack/bin/gjspack src/langs/css/prettier.js src/langs/css && ./src/langs/css/prettier --stdin-filepath src/style.css
+
+import { exit } from "system";
+import Gio from "gi://Gio";
+
+import { format } from "../../lib/prettier.js";
+import prettier_postcss from "../../lib/prettier-postcss.js";
+
+const idx = ARGV.indexOf("--stdin-filepath");
+if (idx < 0) exit(1);
+const filename = ARGV[idx + 1];
+if (!filename) exit(1);
+
+const file = Gio.File.new_for_path(filename);
+const [, contents] = file.load_contents(null);
+const text = new TextDecoder().decode(contents);
+
+const formatted = await format(text, {
+  parser: "css",
+  plugins: [prettier_postcss],
+});
+
+// eslint-disable-next-line no-restricted-globals
+print(formatted);