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/__tests__/createMockFlipperWithPlugin.node.tsx

@@ -0,0 +1,63 @@
+/**
+ * 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 {createMockFlipperWithPlugin} from '../test-utils/createMockFlipperWithPlugin';
+import {FlipperPlugin} from '../plugin';
+
+interface PersistedState {
+  count: 1;
+}
+
+class TestPlugin extends FlipperPlugin<any, any, any> {
+  static id = 'TestPlugin';
+
+  static defaultPersistedState = {
+    count: 0,
+  };
+
+  static persistedStateReducer(
+    persistedState: PersistedState,
+    method: string,
+    _payload: {},
+  ) {
+    if (method === 'inc') {
+      return Object.assign({}, persistedState, {
+        count: persistedState.count + 1,
+      });
+    }
+    return persistedState;
+  }
+
+  render() {
+    return null;
+  }
+}
+
+test('can create a Fake flipper', async () => {
+  await createMockFlipperWithPlugin(
+    TestPlugin,
+    async ({client, device, store, sendMessage}) => {
+      expect(client).toBeTruthy();
+      expect(device).toBeTruthy();
+      expect(store).toBeTruthy();
+      expect(sendMessage).toBeTruthy();
+      expect(client.plugins.includes(TestPlugin.id)).toBe(true);
+      expect(store.getState().connections).toMatchSnapshot();
+      expect(store.getState().plugins).toMatchSnapshot();
+      sendMessage('inc', {});
+      expect(store.getState().pluginStates).toMatchInlineSnapshot(`
+        Object {
+          "TestApp#Android#MockAndroidDevice#serial#TestPlugin": Object {
+            "count": 1,
+          },
+        }
+      `);
+    },
+  );
+});