Dev mode: fixed loading plugins located outside of the Flipper source root folder

Summary: Dev mode: fixed loading of plugins located outside of the Flipper source root folder, e.g. in ~/flipper-plugins as suggested in tutorial docs.

Reviewed By: passy

Differential Revision: D21306639

fbshipit-source-id: bb9044b25324065f0c12169b95fbe663da8d4305

desktop/static/ensurePluginFoldersWatchable.ts

@@ -0,0 +1,38 @@
+/**
+ * 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 getPluginFolders from './getPluginFolders';
+import fs from 'fs-extra';
+
+const watchmanconfigName = '.watchmanconfig';
+
+import path from 'path';
+
+export default async function ensurePluginFoldersWatchable() {
+  const pluginFolders = await getPluginFolders();
+  for (const pluginFolder of pluginFolders) {
+    if (!(await hasParentWithWatchmanConfig(pluginFolder))) {
+      // If no watchman config found in the plugins folder or any its parent, we need to create it.
+      // Otherwise we won't be able to listen for plugin changes.
+      await fs.writeJson(path.join(pluginFolder, watchmanconfigName), {});
+    }
+  }
+}
+
+async function hasParentWithWatchmanConfig(dir: string): Promise<boolean> {
+  if (await fs.pathExists(path.join(dir, watchmanconfigName))) {
+    return true;
+  } else {
+    const parent = path.dirname(dir);
+    if (parent && parent != '' && parent !== dir) {
+      return await hasParentWithWatchmanConfig(parent);
+    }
+  }
+  return false;
+}