Binding outside lifecycle causes instant completion

Before, it would throw an exception, which doesn't make as much sense - if
the logic worked out such that you bound outside the lifecycle, that prboably
meant that you just don't want the subscription to occur outside the
lifecycle, so it should end immediately.

rxlifecycle/src/main/java/com/trello/rxlifecycle/RxLifecycle.java

@@ -15,11 +15,10 @@
 package com.trello.rxlifecycle;
 
 import android.view.View;
-
 import com.jakewharton.rxbinding.view.RxView;
 import com.jakewharton.rxbinding.view.ViewAttachEvent;
-
 import rx.Observable;
+import rx.exceptions.Exceptions;
 import rx.functions.Func1;
 import rx.functions.Func2;
 
@@ -214,6 +213,17 @@ public Boolean call(R bindUntilEvent, R lifecycleEvent) {
                                 return lifecycleEvent == bindUntilEvent;
                             }
                         })
+                        .onErrorReturn(new Func1<Throwable, Boolean>() {
+                            @Override
+                            public Boolean call(Throwable throwable) {
+                                if (throwable instanceof IllegalStateException) {
+                                    return true;
+                                }
+
+                                Exceptions.propagate(throwable);
+                                return false;
+                            }
+                        })
                         .takeFirst(new Func1<Boolean, Boolean>() {
                             @Override
                             public Boolean call(Boolean shouldComplete) {

rxlifecycle/src/test/java/com/trello/rxlifecycle/RxLifecycleTest.java

@@ -16,22 +16,20 @@
 
 import android.app.Activity;
 import android.view.View;
-
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.robolectric.Robolectric;
 import org.robolectric.RobolectricTestRunner;
 import org.robolectric.annotation.Config;
-
-import java.util.concurrent.CopyOnWriteArrayList;
-
 import rx.Observable;
 import rx.Subscription;
 import rx.observers.TestSubscriber;
 import rx.subjects.BehaviorSubject;
 import rx.subjects.PublishSubject;
 
+import java.util.concurrent.CopyOnWriteArrayList;
+
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
@@ -137,13 +135,15 @@ public void testBindActivityLifecycle() {
         stopTestSub.assertUnsubscribed();
     }
 
-    public void testThrowsExceptionOutsideActivityLifecycle() {
+    @Test
+    public void testEndsImmediatelyOutsideActivityLifecycle() {
         BehaviorSubject<ActivityEvent> lifecycle = BehaviorSubject.create();
         lifecycle.onNext(ActivityEvent.DESTROY);
 
         TestSubscriber<Object> testSubscriber = new TestSubscriber<>();
         observable.compose(RxLifecycle.bindActivity(lifecycle)).subscribe(testSubscriber);
-        testSubscriber.assertError(IllegalStateException.class);
+        testSubscriber.assertCompleted();
+        testSubscriber.assertUnsubscribed();
     }
 
     @Test
@@ -227,13 +227,15 @@ public void testBindFragmentLifecycle() {
         destroyTestSub.assertUnsubscribed();
     }
 
-    public void testThrowsExceptionOutsideFragmentLifecycle() {
+    @Test
+    public void testEndsImmediatelyOutsideFragmentLifecycle() {
         BehaviorSubject<FragmentEvent> lifecycle = BehaviorSubject.create();
         lifecycle.onNext(FragmentEvent.DETACH);
 
         TestSubscriber<Object> testSubscriber = new TestSubscriber<>();
         observable.compose(RxLifecycle.bindFragment(lifecycle)).subscribe(testSubscriber);
-        testSubscriber.assertError(IllegalStateException.class);
+        testSubscriber.assertCompleted();
+        testSubscriber.assertUnsubscribed();
     }
 
     @Test