Update preinstall script to enable use as a Git dependency

Author: alexeyr

react_on_rails_pro/package.json

@@ -100,10 +100,11 @@
     }
   },
   "files": [
-    "packages/node-renderer/dist"
+    "packages/node-renderer/dist",
+    "script/preinstall.js"
   ],
   "scripts": {
-    "preinstall": "yarn run link-source && yalc add --link react-on-rails",
+    "preinstall": "node ./script/preinstall.js",
     "postinstall": "test -f post-yarn-install.local && ./post-yarn-install.local || true",
     "link-source": "cd ../packages/react-on-rails && yarn && yalc publish",
     "test": "nps test",

react_on_rails_pro/script/preinstall.js

@@ -0,0 +1,31 @@
+#!/usr/bin/env node
+
+const path = require('path');
+const cp = require('child_process');
+
+const inNodeModules = __dirname.split(path.sep).includes('node_modules');
+
+if (inNodeModules) {
+  console.log('preinstall: running inside node_modules — skipping link steps.');
+  process.exit(0);
+}
+
+function runCommand(cmd, args) {
+  const res = cp.spawnSync(cmd, args, { stdio: 'inherit' });
+  if (res.error) throw res.error;
+  if (res.status !== 0) throw new Error(`${cmd} ${args.join(' ')} exited with status ${res.status}`);
+}
+
+try {
+  // Run the original optional link steps sequentially in a cross-platform way.
+  // First run the package script `link-source` via yarn, which will run any shell ops inside the script
+  // (yarn itself will handle invoking a shell for the script body), then call yalc.
+  runCommand('yarn', ['run', 'link-source']);
+  runCommand('yalc', ['add', '--link', 'react-on-rails']);
+} catch (err) {
+  // Don't fail the overall install if these optional commands aren't available or fail,
+  // just log the error.
+  console.error('preinstall: optional link steps failed or are unavailable — continuing.', err);
+  // Keep the exit code 0 so the install doesn't fail.
+  process.exit(0);
+}