Make sure Sandy Device Plugins can be unit testsed

Summary: Add unit tests to verify that the unit test utilities for for Sandy device plugins work as expected. Fixed a bug revealed by that and cleaned up some TODO's

Reviewed By: jknoxville, passy, nikoant

Differential Revision: D22693928

fbshipit-source-id: 93162db19d826d0cd7f642cef1447fd756261ac8

desktop/app/src/dispatcher/__tests__/plugins.node.tsx

@@ -265,6 +265,7 @@ test('requirePlugin loads valid Sandy plugin', () => {
     title: 'Sample',
     version: '1.0.0',
   });
+  expect(plugin.isDevicePlugin).toBe(false);
   expect(typeof plugin.module.Component).toBe('function');
   expect(plugin.module.Component.displayName).toBe('FlipperPlugin(Sample)');
   expect(typeof plugin.asPluginModule().plugin).toBe('function');
@@ -286,3 +287,38 @@ test('requirePlugin errors on invalid Sandy plugin', () => {
     `"Flipper plugin 'Sample' should export named function called 'plugin'"`,
   );
 });
+
+test('requirePlugin loads valid Sandy Device plugin', () => {
+  const name = 'pluginID';
+  const requireFn = requirePlugin([], {}, require);
+  const plugin = requireFn({
+    ...samplePluginDetails,
+    name,
+    entry: path.join(
+      __dirname,
+      '../../../../flipper-plugin/src/__tests__/DeviceTestPlugin',
+    ),
+    version: '1.0.0',
+    flipperSDKVersion: '0.0.0',
+  }) as SandyPluginDefinition;
+  expect(plugin).not.toBeNull();
+  // @ts-ignore
+  expect(plugin).toBeInstanceOf(SandyPluginDefinition);
+  expect(plugin.id).toBe('Sample');
+  expect(plugin.details).toMatchObject({
+    flipperSDKVersion: '0.0.0',
+    id: 'Sample',
+    isDefault: false,
+    main: 'dist/bundle.js',
+    name: 'pluginID',
+    source: 'src/index.js',
+    specVersion: 2,
+    title: 'Sample',
+    version: '1.0.0',
+  });
+  expect(plugin.isDevicePlugin).toBe(true);
+  expect(typeof plugin.module.Component).toBe('function');
+  expect(plugin.module.Component.displayName).toBe('FlipperPlugin(Sample)');
+  expect(typeof plugin.asDevicePluginModule().devicePlugin).toBe('function');
+  expect(typeof plugin.asDevicePluginModule().supportsDevice).toBe('function');
+});

desktop/flipper-plugin/src/__tests__/DeviceTestPlugin.tsx

@@ -0,0 +1,60 @@
+/**
+ * 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 * as React from 'react';
+import {DevicePluginClient, Device} from '../plugin/DevicePlugin';
+import {usePlugin} from '../plugin/PluginContext';
+import {createState, useValue} from '../state/atom';
+
+export function supportsDevice(_device: Device) {
+  return true;
+}
+
+export function devicePlugin(client: DevicePluginClient) {
+  const logStub = jest.fn();
+  const activateStub = jest.fn();
+  const deactivateStub = jest.fn();
+  const destroyStub = jest.fn();
+  const state = createState(
+    {
+      count: 0,
+    },
+    {
+      persist: 'counter',
+    },
+  );
+
+  client.device.onLogEntry((entry) => {
+    state.update((d) => {
+      d.count++;
+    });
+    logStub(entry);
+  });
+  client.onActivate(activateStub);
+  client.onDeactivate(deactivateStub);
+  client.onDestroy(destroyStub);
+
+  return {
+    logStub,
+    activateStub,
+    deactivateStub,
+    destroyStub,
+    state,
+  };
+}
+
+export function Component() {
+  const api = usePlugin(devicePlugin);
+  const count = useValue(api.state).count;
+
+  // @ts-expect-error
+  api.bla;
+
+  return <h1>Hi from test plugin {count}</h1>;
+}

desktop/flipper-plugin/src/__tests__/test-utils-device.node.tsx

@@ -0,0 +1,151 @@
+/**
+ * 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 * as TestUtils from '../test-utils/test-utils';
+import * as testPlugin from './DeviceTestPlugin';
+import {createState} from '../state/atom';
+
+const testLogMessage = {
+  date: new Date(),
+  message: 'test',
+  pid: 0,
+  tid: 0,
+  tag: 'bla',
+  type: 'warn',
+  app: 'TestApp',
+} as const;
+
+test('it can start a device plugin and listen to lifecycle events', () => {
+  const {instance, ...p} = TestUtils.startDevicePlugin(testPlugin);
+
+  // @ts-expect-error
+  p.bla;
+  // @ts-expect-error
+  instance.bla;
+
+  // startPlugin starts activated
+  expect(instance.activateStub).toBeCalledTimes(1);
+  expect(instance.deactivateStub).toBeCalledTimes(0);
+  expect(instance.destroyStub).toBeCalledTimes(0);
+
+  // calling activate is a noop
+  p.activate();
+  expect(instance.activateStub).toBeCalledTimes(1);
+  expect(instance.deactivateStub).toBeCalledTimes(0);
+  expect(instance.destroyStub).toBeCalledTimes(0);
+
+  p.sendLogEntry(testLogMessage);
+  expect(instance.logStub).toBeCalledWith(testLogMessage);
+  expect(instance.state.get().count).toBe(1);
+
+  expect(instance.activateStub).toBeCalledTimes(1);
+  expect(instance.deactivateStub).toBeCalledTimes(0);
+  expect(instance.destroyStub).toBeCalledTimes(0);
+
+  p.deactivate();
+  p.activate();
+
+  expect(instance.activateStub).toBeCalledTimes(2);
+  expect(instance.deactivateStub).toBeCalledTimes(1);
+  expect(instance.destroyStub).toBeCalledTimes(0);
+
+  p.destroy();
+  expect(instance.activateStub).toBeCalledTimes(2);
+  expect(instance.deactivateStub).toBeCalledTimes(2);
+  expect(instance.destroyStub).toBeCalledTimes(1);
+
+  // cannot interact with destroyed plugin
+  expect(() => {
+    p.activate();
+  }).toThrowErrorMatchingInlineSnapshot(`"Plugin has been destroyed already"`);
+});
+
+test('it can render a device plugin', () => {
+  const {renderer, instance, sendLogEntry} = TestUtils.renderDevicePlugin(
+    testPlugin,
+  );
+
+  expect(renderer.baseElement).toMatchInlineSnapshot(`
+    <body>
+      <div>
+        <h1>
+          Hi from test plugin 
+          0
+        </h1>
+      </div>
+    </body>
+  `);
+
+  sendLogEntry(testLogMessage);
+
+  expect(renderer.baseElement).toMatchInlineSnapshot(`
+    <body>
+      <div>
+        <h1>
+          Hi from test plugin 
+          1
+        </h1>
+      </div>
+    </body>
+  `);
+
+  // @ts-ignore
+  expect(instance.state.listeners.length).toBe(1);
+  renderer.unmount();
+  // @ts-ignore
+  expect(instance.state.listeners.length).toBe(0);
+});
+
+test('device plugins support non-serializable state', async () => {
+  const {exportState} = TestUtils.startPlugin({
+    plugin() {
+      const field1 = createState(true);
+      const field2 = createState(
+        {
+          test: 3,
+        },
+        {
+          persist: 'field2',
+        },
+      );
+      return {
+        field1,
+        field2,
+      };
+    },
+    Component() {
+      return null;
+    },
+  });
+  // states are serialized in creation order
+  expect(exportState()).toEqual({field2: {test: 3}});
+});
+
+test('device plugins support restoring state', async () => {
+  const {exportState} = TestUtils.startPlugin(
+    {
+      plugin() {
+        const field1 = createState(1, {persist: 'field1'});
+        const field2 = createState(2);
+        const field3 = createState(3, {persist: 'field3'});
+        expect(field1.get()).toBe('a');
+        expect(field2.get()).toBe(2);
+        expect(field3.get()).toBe('b');
+        return {};
+      },
+      Component() {
+        return null;
+      },
+    },
+    {
+      initialState: {field1: 'a', field3: 'b'},
+    },
+  );
+  expect(exportState()).toEqual({field1: 'a', field3: 'b'});
+});

desktop/flipper-plugin/src/plugin/DevicePlugin.tsx

@@ -137,28 +137,9 @@ export class SandyDevicePluginInstance {
       this.activated = true;
       this.events.emit('activate');
     }
-    // TODO:
-    // const pluginId = this.definition.id;
-    // if (!this.realClient.isBackgroundPlugin(pluginId)) {
-    //   this.realClient.initPlugin(pluginId); // will call connect() if needed
-    // }
   }
 
-  // the plugin is deselected in the UI
   deactivate() {
-    // TODO:
-    // if (this.destroyed) {
-    //   // this can happen if the plugin is disabled while active in the UI.
-    //   // In that case deinit & destroy is already triggered from the STAR_PLUGIN action
-    //   return;
-    // }
-    // const pluginId = this.definition.id;
-    // if (!this.realClient.isBackgroundPlugin(pluginId)) {
-    //   this.realClient.deinitPlugin(pluginId);
-    // }
-  }
-
-  disconnect() {
     this.assertNotDestroyed();
     if (this.activated) {
       this.activated = false;
@@ -168,10 +149,7 @@ export class SandyDevicePluginInstance {
 
   destroy() {
     this.assertNotDestroyed();
-    // TODO:
-    // if (this.activated) {
-    //   this.realClient.deinitPlugin(this.definition.id);
-    // }
+    this.deactivate();
     this.events.emit('destroy');
     this.destroyed = true;
   }

desktop/flipper-plugin/src/test-utils/test-utils.tsx

@@ -251,7 +251,7 @@ export function startDevicePlugin<Module extends FlipperDevicePluginModule>(
     createMockPluginDetails(),
     module,
   );
-  if (definition.isDevicePlugin) {
+  if (!definition.isDevicePlugin) {
     throw new Error(
       'Use `startPlugin` or `renderPlugin` to test non-device plugins',
     );