build: replace fs-extra, node-watch, meow and rimraf with Node built-ins (#992)

* build: replace fs-extra, node-watch, meow and rimraf with Node builtins

These build scripts predate much of what is now in the Node standard
library. On Node 24 each maps to a builtin: fs-extra to fs.cpSync/rmSync/
mkdirSync recursive, rimraf to fs.rmSync plus fs.globSync for the one
--glob case, meow to util.parseArgs, and node-watch to fs.watch recursive
(which works on Linux since Node 19, and the watched src dir is small).

shx stays for now: its only use is the update-ufuzzy script, which goes
away together with the vendored file in the uFuzzy build-copy change, so
that removal lives there rather than here.

Note: AI-assisted (Claude Code). Manually verified by running yarn clean and a from-scratch yarn build so every rewritten script executed, checking fs.globSync('*.lock') matches and removes the right files, and confirming Node 19+ recursive watch on Linux before dropping node-watch.

* fix: run rm.js from the package root, drop the ignored copySync arg

The conda-lock and extract scripts cd into a subdir first and then called
node scripts/rm.js, but that path only resolves from the repo root, so the
removal failed with a module-not-found once the cwd changed. npm and yarn
always start a run-script at the package root, so the natural fix is to do
the removal there against a root-relative target and let the later cd handle
only conda-lock and tar, which genuinely need the subdir. This avoids a
../scripts/rm.js form that would recouple the path to the cd depth.

copySync already hardcodes { recursive: true } in its definition, so the
third argument passed at the copy-extras call site was silently ignored;
removing it keeps the recursive copy and drops the misleading option.

Note: AI-assisted (Claude Code). Manually verified: rm.js from root cwd with
a subdir glob and a glob-miss both remove the right paths and exit 0;
copySync copies a nested tree; type-check, 443 unit tests and yarn build all
pass on the merged branch.

* test: cover scripts/rm.js, the native rimraf replacement

rm.js was the one piece of new logic in this PR with no coverage: glob
detection, glob expansion, recursive removal and missing-path tolerance all
lived only in the build/conda npm scripts, which the installer CI exercises
end to end but which nothing pins at the unit level.

Expose an rm(args) function and keep the CLI behavior behind a
require.main === module guard so the same file can be imported by the test
and still run as node scripts/rm.js. The test uses a real tmpdir and absolute
glob patterns so it does not depend on cwd (fs.globSync resolves relative
patterns against process.cwd, and chdir is unavailable in worker threads).

Note: AI-assisted (Claude Code). Manually verified: the 6 cases pass; mutation
checks confirm they are not tautological (recursive:false and force:false make
three of them fail, dropping the glob branch fails the glob case); the CLI form
still removes via argv after the refactor; type-check, 449 unit tests and yarn
build pass.

* style: single-line the fs import in rm.test.ts for prettier

The multi-line import tripped prettier:check (it fits on one line under the
repo width), which failed the Lint step. No behavior change.

Note: AI-assisted (Claude Code). Manually verified: prettier:check and
eslint:check both clean on the full tree.

---------

Co-authored-by: Michał Krassowski <5832902+krassowski@users.noreply.github.com>

Author: notluquis

package.json

@@ -10,7 +10,7 @@
     "test:unit:watch": "vitest",
     "test:coverage": "vitest run --coverage",
     "test:e2e": "playwright test",
-    "clean": "rimraf build dist",
+    "clean": "node scripts/rm.js build dist",
     "watch:tsc": "tsc -w",
     "watch:assets": "node ./scripts/extract.js && node ./scripts/copyassets.js watch",
     "watch": "concurrently \"yarn watch:tsc\" \"yarn watch:assets\" ",
@@ -30,19 +30,19 @@
     "dist:osx-arm64-dev": "yarn build && CSC_IDENTITY_AUTO_DISCOVERY=false electron-builder --macos --arm64 --publish never",
     "dist:win-64": "yarn build && electron-builder --win --publish never",
     "dist:win-arm64": "yarn build && yarn electron-builder --arm64 --publish never",
-    "update_workflow_conda_lock": "cd workflow_env && rimraf --glob *.lock && conda-lock --kind explicit -f publish_env.yaml && cd -",
-    "update_conda_lock": "cd env_installer && rimraf --glob *.lock && conda-lock --kind explicit -f jlab_server.yaml && cd -",
-    "clean_env_installer": "rimraf ./env_installer/jlab_server.tar.gz && rimraf ./env_installer/jlab_server",
+    "update_workflow_conda_lock": "node scripts/rm.js workflow_env/*.lock && cd workflow_env && conda-lock --kind explicit -f publish_env.yaml && cd -",
+    "update_conda_lock": "node scripts/rm.js env_installer/*.lock && cd env_installer && conda-lock --kind explicit -f jlab_server.yaml && cd -",
+    "clean_env_installer": "node scripts/rm.js ./env_installer/jlab_server.tar.gz && node scripts/rm.js ./env_installer/jlab_server",
     "create_env_installer": "yarn clean_env_installer && conda-lock install --no-validate-platform --prefix ./env_installer/jlab_server ./env_installer/conda-${ENV_PLATFORM}.lock && yarn copy_extras_to_bundled_env && conda pack -p ./env_installer/jlab_server -o ./env_installer/jlab_server.tar.gz",
     "create_env_installer:linux-64": "ENV_PLATFORM=linux-64 yarn create_env_installer",
     "create_env_installer:linux-aarch64": "ENV_PLATFORM=linux-aarch64 yarn create_env_installer",
     "create_env_installer:osx-64": "ENV_PLATFORM=osx-64 yarn create_env_installer",
     "create_env_installer:osx-arm64": "ENV_PLATFORM=osx-arm64 yarn create_env_installer",
     "create_env_installer:win-64": "yarn clean_env_installer && conda-lock install --no-validate-platform --prefix ./env_installer/jlab_server ./env_installer/conda-win-64.lock && yarn copy_extras_to_bundled_env && conda pack -p ./env_installer/jlab_server -o ./env_installer/jlab_server.tar.gz",
-    "extract_env_installer:osx": "cd ./env_installer && rimraf jlab_server_extracted && mkdir jlab_server_extracted && tar -xzf jlab_server.tar.gz -C jlab_server_extracted && cd -",
+    "extract_env_installer:osx": "node scripts/rm.js env_installer/jlab_server_extracted && cd ./env_installer && mkdir jlab_server_extracted && tar -xzf jlab_server.tar.gz -C jlab_server_extracted && cd -",
     "extract_env_installer:osx-64": "yarn extract_env_installer:osx",
     "extract_env_installer:osx-arm64": "yarn extract_env_installer:osx",
-    "compress_env_installer:osx": "rimraf ./env_installer/jlab_server.tar.gz && cd ./env_installer/jlab_server_extracted && tar -czf ../jlab_server.tar.gz . && cd -",
+    "compress_env_installer:osx": "node scripts/rm.js ./env_installer/jlab_server.tar.gz && cd ./env_installer/jlab_server_extracted && tar -czf ../jlab_server.tar.gz . && cd -",
     "compress_env_installer:osx-64": "yarn compress_env_installer:osx",
     "compress_env_installer:osx-arm64": "yarn compress_env_installer:osx",
     "check_version_match": "node scripts/buildutil.js --check-version-match",
@@ -199,14 +199,10 @@
     "electron-playwright-helpers": "^2.1.0",
     "eslint": "^10.5.0",
     "eslint-config-prettier": "^10.1.8",
-    "fs-extra": "^11.3.5",
     "globals": "^17.6.0",
     "istextorbinary": "^9.5.0",
-    "meow": "^9.0.0",
-    "node-watch": "^0.7.4",
     "prettier": "~2.1.1",
     "read-package-tree": "^5.1.6",
-    "rimraf": "^4.4.1",
     "shx": "^0.4.0",
     "typescript": "^6.0.0",
     "typescript-eslint": "^8.61.1",

scripts/buildutil.js

@@ -1,51 +1,33 @@
-const meow = require('meow');
-const fs = require('fs-extra');
+const { parseArgs } = require('util');
+const fs = require('fs');
 const path = require('path');
 const semver = require('semver');
 const yaml = require('js-yaml');
 
+// Native replacements for the fs-extra helpers this script used.
+const readJSONSync = p => JSON.parse(fs.readFileSync(p, 'utf8'));
+const copySync = (src, dest) => fs.cpSync(src, dest, { recursive: true });
+
 const pkgjsonFilePath = path.resolve(__dirname, '../package.json');
 
-const cli = meow(
-  `
-    Usage
-      $ node buildutil <options>
-
-    Options
-      --check-version-match         check for JupyterLab version match
-      --update-binary-sign-list     update binary list to sign for macOS
-      --copy-extras-to-bundled-env  copy extra files from extras to bundled environment installer
-      --platform                    platform for --update-binary-sign-list. osx-64 or osx-arm64
-
-    Other options:
-      --help                        show usage information
-      --version                     show version information
-
-    Examples
-      $ node buildutil --check-version-match
-`,
-  {
-    flags: {
-      checkVersionMatch: {
-        type: 'boolean',
-        default: false
-      },
-      updateBinarySignList: {
-        type: 'boolean',
-        default: false
-      },
-      platform: {
-        type: 'string',
-        default: 'osx-64'
-      }
-    }
+// node buildutil <options>
+//   --check-version-match         check for JupyterLab version match
+//   --update-binary-sign-list     update binary list to sign for macOS
+//   --copy-extras-to-bundled-env  copy extras into the bundled environment
+//   --platform <osx-64|osx-arm64> platform for --update-binary-sign-list
+const { values: flags } = parseArgs({
+  options: {
+    'check-version-match': { type: 'boolean', default: false },
+    'update-binary-sign-list': { type: 'boolean', default: false },
+    'copy-extras-to-bundled-env': { type: 'boolean', default: false },
+    platform: { type: 'string', default: 'osx-64' }
   }
-);
+});
 
-if (cli.flags.checkVersionMatch) {
+if (flags['check-version-match']) {
   // parse application version
   const pkgjsonFileData = fs.existsSync(pkgjsonFilePath)
-    ? fs.readJSONSync(pkgjsonFilePath)
+    ? readJSONSync(pkgjsonFilePath)
     : undefined;
   if (!pkgjsonFileData) {
     console.error('package.json not found!');
@@ -91,7 +73,7 @@ if (cli.flags.checkVersionMatch) {
   process.exit(0);
 }
 
-if (cli.flags.updateBinarySignList) {
+if (flags['update-binary-sign-list']) {
   const { isBinary } = require('istextorbinary');
   const envInstallerDir = path.resolve('env_installer', 'jlab_server');
 
@@ -172,10 +154,7 @@ if (cli.flags.updateBinarySignList) {
 
   const binaries = findBinariesInDirectory(envInstallerDir);
   const fileContent = binaries.join('\n');
-  const signListFile = path.join(
-    'env_installer',
-    `sign-${cli.flags.platform}.txt`
-  );
+  const signListFile = path.join('env_installer', `sign-${flags.platform}.txt`);
 
   fs.writeFileSync(signListFile, `${fileContent}\n`);
 
@@ -184,11 +163,11 @@ if (cli.flags.updateBinarySignList) {
   process.exit(0);
 }
 
-if (cli.flags.copyExtrasToBundledEnv) {
+if (flags['copy-extras-to-bundled-env']) {
   const envExtrasDir = path.resolve('env_installer', 'extras');
   const envInstallerDir = path.resolve('env_installer', 'jlab_server');
 
-  fs.copySync(envExtrasDir, envInstallerDir, { recursive: true });
+  copySync(envExtrasDir, envInstallerDir);
 
   console.log(
     `Finished copying env extras from \n\t"${envExtrasDir}" to \n\t"${envInstallerDir}"`

scripts/copyassets.js

@@ -1,6 +1,8 @@
 const path = require('path');
-const fs = require('fs-extra');
-const watch = require('node-watch');
+const fs = require('fs');
+
+// fs-extra's copySync replaced with the native recursive cp (Node 16.7+).
+const copySync = (src, dest) => fs.cpSync(src, dest, { recursive: true });
 
 const platform = process.platform;
 const buildDir = path.resolve('./build');
@@ -39,40 +41,38 @@ function copyAssests() {
     const destPath = srcPath.replace(srcDir, dest);
 
     if (srcPath.includes('style') || srcPath.includes('img')) {
-      fs.copySync(srcPath, destPath);
+      copySync(srcPath, destPath);
     }
   });
 
   const titlebarPath = path.join('main', 'titlebarview', 'titlebar.html');
-  fs.copySync(
+  copySync(
     path.join(srcDir, titlebarPath),
     path.join(dest, '../app-assets', 'titlebarview', 'titlebar.html')
   );
 
-  fs.copySync(path.join(srcDir, 'assets'), path.join(dest, '../app-assets'), {
-    recursive: true
-  });
+  copySync(path.join(srcDir, 'assets'), path.join(dest, '../app-assets'));
 
   const toolkitPath = path.join(
     '../node_modules',
     '@jupyter-notebook/web-components',
     'dist'
   );
-  fs.copySync(
+  copySync(
     path.join(srcDir, toolkitPath, 'toolkit.min.js'),
     path.join(dest, '../jupyter-ui-toolkit/toolkit.min.js')
   );
-  fs.copySync(
+  copySync(
     path.join(srcDir, toolkitPath, 'toolkit.js'),
     path.join(dest, '../jupyter-ui-toolkit/toolkit.js')
   );
 
   const envInfoPath = path.join('main', 'env_info.py');
-  fs.copySync(path.join(srcDir, envInfoPath), path.join(dest, envInfoPath));
+  copySync(path.join(srcDir, envInfoPath), path.join(dest, envInfoPath));
 
   // Copy install scripts
   if (platform === 'darwin') {
-    fs.copySync(
+    copySync(
       path.join(
         path.resolve('./'),
         'dist-resources',
@@ -82,7 +82,7 @@ function copyAssests() {
       path.join(buildDir, 'entitlements.plist')
     );
   } else if (platform === 'win32') {
-    fs.copySync(
+    copySync(
       path.join(
         path.resolve('./'),
         'electron-builder-scripts',
@@ -91,20 +91,17 @@ function copyAssests() {
       path.join(buildDir, 'wininstall.nsh')
     );
   } else {
-    fs.copySync(
+    copySync(
       path.join(
         path.resolve('./'),
         'electron-builder-scripts',
         'linux_after_install.sh'
       ),
       path.join(buildDir, 'linux_after_install.sh')
     );
-    fs.copySync(
+    copySync(
       path.join(path.resolve('./'), 'electron-builder-scripts', 'snap-hooks'),
-      path.join(buildDir, 'snap-hooks'),
-      {
-        recursive: true
-      }
+      path.join(buildDir, 'snap-hooks')
     );
   }
 
@@ -113,9 +110,12 @@ function copyAssests() {
 copyAssests();
 
 if (process.argv.length > 2 && process.argv[2] == 'watch') {
-  watch(srcDir, { recursive: true }, function (evt, name) {
-    if (/(\.css$)|(\.html$)/.test(name)) {
-      console.log('Asset chage detected.');
+  // native fs.watch replaces node-watch; recursive watch works on macOS,
+  // Windows, and Linux (Node 19+ walks the tree itself). srcDir is small so
+  // the per-directory inotify watches on Linux are not a concern.
+  fs.watch(srcDir, { recursive: true }, function (evt, name) {
+    if (name && /(\.css$)|(\.html$)/.test(name)) {
+      console.log('Asset change detected.');
       copyAssests();
     }
   });

scripts/extract.js

@@ -1,17 +1,22 @@
 var rpt = require('read-package-tree');
 var path = require('path');
-var fs = require('fs-extra');
+var fs = require('fs');
 var glob = require('glob');
 
+// Native replacements for the fs-extra helpers this script used.
+var removeSync = p => fs.rmSync(p, { recursive: true, force: true });
+var ensureDirSync = d => fs.mkdirSync(d, { recursive: true });
+var copySync = (src, dest) => fs.cpSync(src, dest, { recursive: true });
+
 var seen = {};
 
 var schemaDest = path.resolve('./build/schemas');
-fs.removeSync(schemaDest);
-fs.ensureDirSync(schemaDest);
+removeSync(schemaDest);
+ensureDirSync(schemaDest);
 
 var themesDest = path.resolve('./build/themes');
-fs.removeSync(themesDest);
-fs.ensureDirSync(themesDest);
+removeSync(themesDest);
+ensureDirSync(themesDest);
 
 function extractNode(data) {
   data.children.forEach(function (child) {
@@ -32,7 +37,7 @@ function extractNode(data) {
   if (schemaDir) {
     const from = path.join(data.realpath, schemaDir);
     const to = path.join(schemaDest, data.package.name);
-    fs.copySync(from, to);
+    copySync(from, to);
   }
 
   // Handle themes.
@@ -41,7 +46,7 @@ function extractNode(data) {
     var themeName = data.package.name;
     const from = path.join(data.realpath, themeDir);
     const to = path.join(themesDest, themeName);
-    fs.copySync(from, to);
+    copySync(from, to);
 
     /**
      * Change relative paths. This is done at runtime by jupyterlab_launcher.

scripts/rm.js

@@ -0,0 +1,19 @@
+// Native replacement for the rimraf CLI used by the npm scripts. Removes each
+// argument recursively and without erroring on missing paths. Arguments
+// containing a glob are expanded with the native fs.globSync (Node 22+).
+const fs = require('fs');
+
+function rm(args) {
+  for (const arg of args) {
+    const targets = /[*?[]/.test(arg) ? fs.globSync(arg) : [arg];
+    for (const target of targets) {
+      fs.rmSync(target, { recursive: true, force: true });
+    }
+  }
+}
+
+if (require.main === module) {
+  rm(process.argv.slice(2));
+}
+
+module.exports = { rm };