Yarn workspaces

Summary:
1) moved "sonar/desktop/src" to "sonar/desktop/app/src", so "app" is now a separate package containing the core Flipper app code
2) Configured yarn workspaces with the root in "sonar/desktop": app, static, pkg, doctor, headless-tests. Plugins are not included for now, I plan to do this later.

Reviewed By: jknoxville

Differential Revision: D20535782

fbshipit-source-id: 600b2301960f37c7d72166e0d04eba462bec9fc1

desktop/app/src/utils/processCleanup.tsx

@@ -0,0 +1,41 @@
+/**
+ * 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 {exec} from 'promisify-child-process';
+import {notNull} from '../utils/typeUtils';
+import {kill} from 'process';
+
+// Kills any orphaned Instruments processes belonging to the user.
+//
+// In some cases, we've seen interactions between Instruments and the iOS
+// simulator that cause hung instruments and DTServiceHub processes. If
+// enough instances pile up, the host machine eventually becomes
+// unresponsive. Until the underlying issue is resolved, manually kill any
+// orphaned instances (where the parent process has died and PPID is 1)
+// before launching another instruments run.
+export async function killOrphanedInstrumentsProcesses() {
+  const result = await exec('ps -e -o user,ppid,pid,comm');
+  result.stdout
+    ?.toString()
+    .split('\n')
+    .filter(notNull)
+    .map(a => /^(\S+)\s+1\s+(\d+)\s+(.+)$/.exec(a))
+    .filter(notNull)
+    .filter(m => m[1] === process.env.USER)
+    .filter(
+      m =>
+        m[3] &&
+        ['/instruments', '/DTServiceHub'].some(name => m[3].endsWith(name)),
+    )
+    .forEach(m => {
+      const pid = m[2];
+      console.debug(`Killing orphaned Instruments process: ${pid}`);
+      kill(parseInt(pid, 10), 'SIGKILL');
+    });
+}