Refactor plugins compilation script

Summary:
Refactored plugins compilation script by splitting it into 3 scripts: 1) search plugins 2) compile plugins 3) watch plugins.

No functional changes in this review, it's just preparation for further changes.

Reviewed By: passy

Differential Revision: D20860443

fbshipit-source-id: 02900430199875574b992e597d09b82d0d7f32ef

desktop/static/getWatchFolders.ts

@@ -0,0 +1,42 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+import fs from 'fs-extra';
+import path from 'path';
+
+export default async (packageDir: string): Promise<string[]> => {
+  if (!(await fs.pathExists(packageDir))) {
+    return [];
+  }
+  const watchDirs: string[] = [packageDir];
+  const pkg = await fs.readJson(path.join(packageDir, 'package.json'));
+  while (true) {
+    const nodeModulesDir = path.join(packageDir, 'node_modules');
+    if (await fs.pathExists(nodeModulesDir)) {
+      watchDirs.push(nodeModulesDir);
+      const modules = await fs.readdir(nodeModulesDir);
+      for (const moduleName of modules) {
+        if (pkg.dependencies && pkg.dependencies[moduleName]) {
+          const fullPath = path.join(nodeModulesDir, moduleName);
+          const stat = await fs.lstat(fullPath);
+          if (stat.isSymbolicLink()) {
+            const target = await fs.readlink(fullPath);
+            watchDirs.push(path.resolve(nodeModulesDir, target));
+          }
+        }
+      }
+    }
+    const nextDir = path.dirname(packageDir);
+    if (!nextDir || nextDir === '/' || nextDir === packageDir) {
+      break;
+    }
+    packageDir = nextDir;
+  }
+  return watchDirs;
+};