Merge pull request #31 from splitwise/close-unbound-fragments

Fix crash on close when previous fragment has been destroyed

enro-core/src/main/java/dev/enro/core/fragment/DefaultFragmentExecutor.kt

@@ -105,22 +105,24 @@ object DefaultFragmentExecutor : NavigationExecutor<Any, Fragment, NavigationKey
         }
 
         val animations = animationsFor(context, NavigationInstruction.Close)
-        val sameFragmentManagers = previousFragment?.parentFragmentManager == context.fragment.parentFragmentManager
+        // Checking for non-null context seems to be the best way to make sure parentFragmentManager will
+        // not throw an IllegalStateException when there is no parent fragment manager
+        val differentFragmentManagers = previousFragment?.context != null && previousFragment.parentFragmentManager != context.fragment.parentFragmentManager
 
         context.fragment.parentFragmentManager.commit {
             setCustomAnimations(animations.enter, animations.exit)
             remove(context.fragment)
 
-            if (previousFragment != null && sameFragmentManagers) {
+            if (previousFragment != null && !differentFragmentManagers) {
                 when {
                     previousFragment.isDetached -> attach(previousFragment)
                     !previousFragment.isAdded -> add(context.contextReference.getContainerId(), previousFragment)
                 }
             }
-            if(sameFragmentManagers) setPrimaryNavigationFragment(previousFragment)
+            if(!differentFragmentManagers) setPrimaryNavigationFragment(previousFragment)
         }
 
-        if(previousFragment != null && !sameFragmentManagers) {
+        if(previousFragment != null && differentFragmentManagers) {
             previousFragment.parentFragmentManager.commit {
                 setPrimaryNavigationFragment(previousFragment)
             }

enro/src/androidTest/java/dev/enro/core/FragmentToFragmentTests.kt

@@ -0,0 +1,81 @@
+package dev.enro.core
+
+import androidx.fragment.app.FragmentActivity
+import androidx.fragment.app.commit
+import androidx.fragment.app.commitNow
+import androidx.test.core.app.ActivityScenario
+import dev.enro.*
+import dev.enro.expectFragment
+import junit.framework.TestCase
+import org.junit.Test
+import java.util.*
+
+private fun expectSingleFragmentActivity(): FragmentActivity {
+    return expectActivity { it::class.java.simpleName == "SingleFragmentActivity"}
+}
+
+class FragmentToFragmentTests {
+
+    @Test
+    fun whenFragmentOpensFragment_andFragmentIsInAHost_thenFragmentIsLaunchedIntoHost() {
+        val scenario = ActivityScenario.launch(ActivityWithFragments::class.java)
+        val handle = scenario.getNavigationHandle<ActivityWithFragmentsKey>()
+
+        val id = UUID.randomUUID().toString()
+        handle.forward(ActivityChildFragmentKey(id))
+
+        val parentFragment = expectFragment<ActivityChildFragment>()
+        val id2 = UUID.randomUUID().toString()
+        parentFragment.getNavigationHandle().forward(ActivityChildFragmentTwoKey(id2))
+
+        val childFragment = expectFragment<ActivityChildFragmentTwo>()
+        val fragmentHandle = childFragment.getNavigationHandle().asTyped<ActivityChildFragmentTwoKey>()
+        TestCase.assertEquals(id2, fragmentHandle.key.id)
+    }
+
+    @Test
+    fun whenFragmentOpensFragment_andFragmentIsNotInAHost_thenFragmentIsLaunchedAsSingleFragmentActivity() {
+        val scenario = ActivityScenario.launch(DefaultActivity::class.java)
+        val handle = scenario.getNavigationHandle<DefaultActivityKey>()
+
+        val id = UUID.randomUUID().toString()
+        handle.forward(ActivityChildFragmentKey(id))
+
+        val activity = expectSingleFragmentActivity()
+        val parentFragment = activity.supportFragmentManager.primaryNavigationFragment!!
+        val id2 = UUID.randomUUID().toString()
+        parentFragment.getNavigationHandle().forward(ActivityChildFragmentTwoKey(id2))
+
+        val activity2 = expectSingleFragmentActivity()
+        val childFragment = activity2.supportFragmentManager.primaryNavigationFragment!!
+        val fragmentHandle = childFragment.getNavigationHandle().asTyped<ActivityChildFragmentTwoKey>()
+        TestCase.assertEquals(id2, fragmentHandle.key.id)
+    }
+
+    @Test
+    fun whenFragmentOpensFragment_andFragmentIsInAHost_andIsDestroyed_thenClosingChildFragmentCreatesNewParentFragment() {
+        val scenario = ActivityScenario.launch(ActivityWithFragments::class.java)
+        val handle = scenario.getNavigationHandle<ActivityWithFragmentsKey>()
+
+        val id = "UUID.randomUUID().toString()"
+        handle.forward(ActivityChildFragmentKey(id))
+
+        val parentFragment = expectFragment<ActivityChildFragment>()
+        val id2 = UUID.randomUUID().toString()
+        parentFragment.getNavigationHandle().forward(ActivityChildFragmentTwoKey(id2))
+
+        val parentFragmentManager = parentFragment.parentFragmentManager
+
+        val childFragment = expectFragment<ActivityChildFragmentTwo>()
+        val fragmentHandle = childFragment.getNavigationHandle().asTyped<ActivityChildFragmentTwoKey>()
+        TestCase.assertEquals(id2, fragmentHandle.key.id)
+
+        // This will destroy the parent fragment, making it unavailable to re-use on close
+        parentFragmentManager.commit { remove(parentFragment) }
+
+        childFragment.getNavigationHandle().close()
+        val newParentFragment = expectFragment<ActivityChildFragment>()
+        TestCase.assertEquals(id, newParentFragment.getNavigationHandle().asTyped<ActivityChildFragmentKey>().key.id)
+        TestCase.assertNotSame(parentFragment, newParentFragment)
+    }
+}

enro/src/androidTest/java/dev/enro/core/UnboundFragmentsTest.kt

@@ -7,8 +7,7 @@ import dev.enro.*
 import org.junit.Ignore
 import org.junit.Test
 
-@Ignore("Something isn't working with the unbound fragment test environment, tests are failing but are known to pass")
-class UnboundFragmentsTest {
+class  UnboundFragmentsTest {
 
     @Test
     fun whenUnboundFragmentIsOpened_thenNavigationKeyIsUnbound() {
@@ -31,7 +30,8 @@ class UnboundFragmentsTest {
             caught = t
         }
         assertTrue(caught is IllegalStateException)
-        assertEquals("This NavigationHandle has no NavigationKey", caught.message)
+        assertNotNull(caught.message)
+        assertTrue(caught.message!!.matches(Regex("The navigation handle for the context UnboundFragment.*has no NavigationKey")))
     }
 
     @Test