[In_App_Purchase] Improve testability

packages/in_app_purchase/CHANGELOG.md

@@ -4,7 +4,7 @@
 
 ## 0.2.1+1
 
-* Android: Do not register if Activity is null.
+* Android: Require Activity only to use launchBillingFlow method.
 
 ## 0.2.1
 

packages/in_app_purchase/android/src/main/java/io/flutter/plugins/inapppurchase/InAppPurchasePlugin.java

@@ -9,6 +9,7 @@
 import static io.flutter.plugins.inapppurchase.Translator.fromSkuDetailsList;
 
 import android.app.Activity;
+import android.content.Context;
 import android.util.Log;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
@@ -35,8 +36,9 @@
 public class InAppPurchasePlugin implements MethodCallHandler {
   private static final String TAG = "InAppPurchasePlugin";
   private @Nullable BillingClient billingClient;
-  private BillingClientFactory factory;
-  private final Activity activity;
+  private final BillingClientFactory factory;
+  private final Registrar registrar;
+  private final Context applicationContext;
   private final MethodChannel channel;
 
   @VisibleForTesting
@@ -65,21 +67,18 @@ static final class MethodNames {
 
   /** Plugin registration. */
   public static void registerWith(Registrar registrar) {
-    final Activity activity = registrar.activity();
-    if (activity == null) {
-      return;
-    }
     final MethodChannel channel =
         new MethodChannel(registrar.messenger(), "plugins.flutter.io/in_app_purchase");
+
     final BillingClientFactory factory = new BillingClientFactory();
-    final InAppPurchasePlugin plugin = new InAppPurchasePlugin(factory, activity, channel);
+    final InAppPurchasePlugin plugin = new InAppPurchasePlugin(factory, registrar, channel);
     channel.setMethodCallHandler(plugin);
   }
 
-  public InAppPurchasePlugin(
-      BillingClientFactory factory, Activity activity, MethodChannel channel) {
+  public InAppPurchasePlugin(BillingClientFactory factory, Registrar registrar, MethodChannel channel) {
+    this.applicationContext = registrar.context();
+    this.registrar = registrar;
     this.factory = factory;
-    this.activity = activity;
     this.channel = channel;
   }
 
@@ -117,9 +116,10 @@ public void onMethodCall(MethodCall call, Result result) {
     }
   }
 
+
   private void startConnection(final int handle, final Result result) {
     if (billingClient == null) {
-      billingClient = factory.createBillingClient(activity, channel);
+      billingClient = factory.createBillingClient(applicationContext, channel);
     }
 
     billingClient.startConnection(
@@ -197,6 +197,17 @@ private void launchBillingFlow(String sku, @Nullable String accountId, Result re
           null);
       return;
     }
+    final Activity activity = registrar.activity();
+
+    if (activity == null) {
+      result.error(
+          "ACTIVITY_UNAVAILABLE",
+          "Details for sku "
+              + sku
+              + " are not available. This method requires to be run with the app in foreground.",
+          null);
+      return;
+    }
 
     BillingFlowParams.Builder paramsBuilder =
         BillingFlowParams.newBuilder().setSkuDetails(skuDetails);

packages/in_app_purchase/example/android/app/src/test/java/io/flutter/plugins/inapppurchase/InAppPurchasePluginTest.java

@@ -29,6 +29,7 @@
 import static org.mockito.Mockito.when;
 
 import android.app.Activity;
+import android.content.Context;
 import androidx.annotation.Nullable;
 import com.android.billingclient.api.BillingClient;
 import com.android.billingclient.api.BillingClient.BillingResponse;
@@ -58,36 +59,22 @@
 import org.mockito.Spy;
 
 public class InAppPurchasePluginTest {
-  InAppPurchasePlugin plugin;
+  private InAppPurchasePlugin plugin;
   @Mock BillingClient mockBillingClient;
   @Mock MethodChannel mockMethodChannel;
   @Spy Result result;
   @Mock PluginRegistry.Registrar registrar;
   @Mock Activity activity;
-  @Mock BinaryMessenger messenger;
   @Mock BillingClientFactory factory;
 
+
   @Before
   public void setUp() {
     MockitoAnnotations.initMocks(this);
     when(factory.createBillingClient(any(), any())).thenReturn(mockBillingClient);
-
-    plugin = new InAppPurchasePlugin(factory, activity, mockMethodChannel);
+    plugin = new InAppPurchasePlugin(factory, registrar, mockMethodChannel);
   }
 
-  @Test
-  public void doNotRegisterWithoutActivityAvailable() {
-    InAppPurchasePlugin.registerWith(registrar);
-    verify(registrar, never()).messenger();
-  }
-
-  @Test
-  public void registerWithoutActivityAvailable() {
-    when(registrar.messenger()).thenReturn(messenger);
-    when(registrar.activity()).thenReturn(activity);
-    InAppPurchasePlugin.registerWith(registrar);
-    verify(registrar).messenger();
-  }
 
   @Test
   public void invalidMethod() {
@@ -236,6 +223,7 @@ public void querySkuDetailsAsync_clientDisconnected() {
 
   @Test
   public void launchBillingFlow_ok_nullAccountId() {
+    when(registrar.activity()).thenReturn(activity);
     // Fetch the sku details first and then prepare the launch billing flow call
     String skuId = "foo";
     queryForSkus(singletonList(skuId));
@@ -262,8 +250,27 @@ public void launchBillingFlow_ok_nullAccountId() {
     verify(result, times(1)).success(responseCode);
   }
 
+  @Test
+  public void launchBillingFlow_ok_null_Activity() {
+    // Fetch the sku details first and then prepare the launch billing flow call
+    String skuId = "foo";
+    String accountId = "account";
+    queryForSkus(singletonList(skuId));
+    HashMap<String, Object> arguments = new HashMap<>();
+    arguments.put("sku", skuId);
+    arguments.put("accountId", accountId);
+    MethodCall launchCall = new MethodCall(LAUNCH_BILLING_FLOW, arguments);
+
+    plugin.onMethodCall(launchCall, result);
+
+    // Verify we pass the response code to result
+    verify(result).error(contains("ACTIVITY_UNAVAILABLE"), contains("foreground"), any());
+    verify(result, never()).success(any());
+  }
+
   @Test
   public void launchBillingFlow_ok_AccountId() {
+    when(registrar.activity()).thenReturn(activity);
     // Fetch the sku details first and query the method call
     String skuId = "foo";
     String accountId = "account";