Move example plugin out of core

Summary:
We should not ship this as part of our distribution.
Just meant we had to bifurcate our unit tests which
is a bit awkward, but it works now.

Reviewed By: jknoxville

Differential Revision: D15146980

fbshipit-source-id: 496b000630bbfcaa663cddacb00550e1499a1279

android/sample/build.gradle

@@ -23,6 +23,12 @@ android {
         main {
             manifest.srcFile './AndroidManifest.xml'
         }
+
+        test {
+            java {
+                exclude 'com/facebook/flipper/plugins/facebook/**'
+            }
+        }
     }
 
     compileOptions {
@@ -52,5 +58,11 @@ dependencies {
     androidTestImplementation deps.testCore
     androidTestImplementation deps.testRules
 
+    // Unit tests
+    testImplementation deps.mockito
+    testImplementation deps.robolectric
+    testImplementation deps.hamcrest
+    testImplementation deps.junit
+
     implementation project(':android')
 }

android/sample/src/main/java/com/facebook/flipper/plugins/example/ExampleFlipperPlugin.java

@@ -0,0 +1,82 @@
+/*
+ *  Copyright (c) 2018-present, Facebook, Inc.
+ *
+ *  This source code is licensed under the MIT license found in the LICENSE
+ *  file in the root directory of this source tree.
+ *
+ */
+package com.facebook.flipper.plugins.example;
+
+import android.app.Activity;
+import android.widget.Toast;
+import androidx.annotation.Nullable;
+import com.facebook.flipper.core.FlipperConnection;
+import com.facebook.flipper.core.FlipperObject;
+import com.facebook.flipper.core.FlipperPlugin;
+import com.facebook.flipper.core.FlipperReceiver;
+import com.facebook.flipper.core.FlipperResponder;
+
+public class ExampleFlipperPlugin implements FlipperPlugin {
+
+  public static final String ID = "Example";
+
+  @Nullable private Activity mActivity;
+
+  @Nullable private FlipperConnection mConnection;
+
+  private int mNotificationsSent = 0;
+
+  @Override
+  public String getId() {
+    return ID;
+  }
+
+  /*
+   * Activity to be used to display incoming messages
+   */
+  public void setActivity(Activity activity) {
+    mActivity = activity;
+  }
+
+  @Override
+  public void onConnect(FlipperConnection connection) {
+    mConnection = connection;
+    connection.receive(
+        "displayMessage",
+        new FlipperReceiver() {
+          @Override
+          public void onReceive(final FlipperObject params, FlipperResponder responder) {
+            if (mActivity != null) {
+              mActivity.runOnUiThread(
+                  new Runnable() {
+                    @Override
+                    public void run() {
+                      Toast.makeText(mActivity, params.getString("message"), Toast.LENGTH_SHORT)
+                          .show();
+                    }
+                  });
+            }
+
+            responder.success(new FlipperObject.Builder().put("greeting", "Hello").build());
+          }
+        });
+  }
+
+  public void triggerNotification() {
+    if (mConnection != null) {
+      mConnection.send(
+          "triggerNotification", new FlipperObject.Builder().put("id", mNotificationsSent).build());
+      mNotificationsSent++;
+    }
+  }
+
+  @Override
+  public void onDisconnect() {
+    mConnection = null;
+  }
+
+  @Override
+  public boolean runInBackground() {
+    return true;
+  }
+}

android/sample/src/test/java/com/facebook/flipper/plugins/example/ExampleFlipperPluginTest.java

@@ -0,0 +1,40 @@
+/*
+ *  Copyright (c) 2018-present, Facebook, Inc.
+ *
+ *  This source code is licensed under the MIT license found in the LICENSE
+ *  file in the root directory of this source tree.
+ *
+ */
+package com.facebook.flipper.plugins.example;
+
+import static org.hamcrest.CoreMatchers.hasItem;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+import com.facebook.flipper.core.FlipperObject;
+import com.facebook.flipper.testing.FlipperConnectionMock;
+import com.facebook.flipper.testing.FlipperResponderMock;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+@RunWith(RobolectricTestRunner.class)
+@Config(application = TestApplication.class)
+public class ExampleFlipperPluginTest {
+
+  @Test
+  public void greetingTest() throws Exception {
+    final ExampleFlipperPlugin plugin = new ExampleFlipperPlugin();
+    final FlipperConnectionMock connection = new FlipperConnectionMock();
+    final FlipperResponderMock responder = new FlipperResponderMock();
+
+    plugin.onConnect(connection);
+    connection
+        .receivers
+        .get("displayMessage")
+        .onReceive(new FlipperObject.Builder().put("message", "test").build(), responder);
+
+    assertThat(
+        responder.successes, hasItem(new FlipperObject.Builder().put("greeting", "Hello").build()));
+  }
+}

android/sample/src/test/java/com/facebook/flipper/plugins/example/TestApplication.java

@@ -0,0 +1,12 @@
+/*
+ *  Copyright (c) 2018-present, Facebook, Inc.
+ *
+ *  This source code is licensed under the MIT license found in the LICENSE
+ *  file in the root directory of this source tree.
+ *
+ */
+package com.facebook.flipper.plugins.example;
+
+import android.app.Application;
+
+public class TestApplication extends Application {}