Add unit testing for pinned last message deletion fix.

app/src/androidTest/java/org/thoughtcrime/securesms/database/ThreadDatabaseTest_pinned.kt

@@ -0,0 +1,74 @@
+package org.thoughtcrime.securesms.database
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.signal.core.util.CursorUtil
+import org.thoughtcrime.securesms.recipients.Recipient
+import org.thoughtcrime.securesms.testing.SignalDatabaseRule
+import org.whispersystems.signalservice.api.push.ServiceId
+import java.util.UUID
+
+@Suppress("ClassName")
+class ThreadDatabaseTest_pinned {
+
+  @Rule
+  @JvmField
+  val databaseRule = SignalDatabaseRule()
+
+  private lateinit var recipient: Recipient
+
+  @Before
+  fun setUp() {
+    recipient = Recipient.resolved(SignalDatabase.recipients.getOrInsertFromServiceId(ServiceId.from(UUID.randomUUID())))
+  }
+
+  @Test
+  fun givenAPinnedThread_whenIDeleteTheLastMessage_thenIDoNotDeleteOrUnpinTheThread() {
+    // GIVEN
+    val threadId = SignalDatabase.threads.getOrCreateThreadIdFor(recipient)
+    val messageId = MmsHelper.insert(recipient = recipient, threadId = threadId)
+    SignalDatabase.threads.pinConversations(listOf(threadId))
+
+    // WHEN
+    SignalDatabase.mms.deleteMessage(messageId)
+
+    // THEN
+    val pinned = SignalDatabase.threads.pinnedThreadIds
+    assertTrue(threadId in pinned)
+  }
+
+  @Test
+  fun givenAPinnedThread_whenIDeleteTheLastMessage_thenIExpectTheThreadInUnarchivedCount() {
+    // GIVEN
+    val threadId = SignalDatabase.threads.getOrCreateThreadIdFor(recipient)
+    val messageId = MmsHelper.insert(recipient = recipient, threadId = threadId)
+    SignalDatabase.threads.pinConversations(listOf(threadId))
+
+    // WHEN
+    SignalDatabase.mms.deleteMessage(messageId)
+
+    // THEN
+    val unarchivedCount = SignalDatabase.threads.unarchivedConversationListCount
+    assertEquals(1, unarchivedCount)
+  }
+
+  @Test
+  fun givenAPinnedThread_whenIDeleteTheLastMessage_thenIExpectPinnedThreadInUnarchivedList() {
+    // GIVEN
+    val threadId = SignalDatabase.threads.getOrCreateThreadIdFor(recipient)
+    val messageId = MmsHelper.insert(recipient = recipient, threadId = threadId)
+    SignalDatabase.threads.pinConversations(listOf(threadId))
+
+    // WHEN
+    SignalDatabase.mms.deleteMessage(messageId)
+
+    // THEN
+    SignalDatabase.threads.getUnarchivedConversationList(true, 0, 1).use {
+      it.moveToFirst()
+      assertEquals(threadId, CursorUtil.requireLong(it, ThreadDatabase.ID))
+    }
+  }
+}

app/src/androidTest/java/org/thoughtcrime/securesms/testing/SignalDatabaseRule.kt

@@ -0,0 +1,40 @@
+package org.thoughtcrime.securesms.testing
+
+import org.junit.rules.TestWatcher
+import org.junit.runner.Description
+import org.thoughtcrime.securesms.database.SignalDatabase
+import org.thoughtcrime.securesms.keyvalue.SignalStore
+import org.whispersystems.signalservice.api.push.ACI
+import org.whispersystems.signalservice.api.push.PNI
+import java.util.UUID
+
+/**
+ * Sets up bare-minimum to allow writing unit tests against the database,
+ * including setting up the local ACI and PNI pair.
+ *
+ * @param deleteAllThreadsOnEachRun Run deleteAllThreads between each unit test
+ */
+class SignalDatabaseRule(
+  private val deleteAllThreadsOnEachRun: Boolean = true
+) : TestWatcher() {
+
+  val localAci: ACI = ACI.from(UUID.randomUUID())
+  val localPni: PNI = PNI.from(UUID.randomUUID())
+
+  override fun starting(description: Description?) {
+    deleteAllThreads()
+
+    SignalStore.account().setAci(localAci)
+    SignalStore.account().setPni(localPni)
+  }
+
+  override fun finished(description: Description?) {
+    deleteAllThreads()
+  }
+
+  private fun deleteAllThreads() {
+    if (deleteAllThreadsOnEachRun) {
+      SignalDatabase.mms.deleteAllThreads()
+    }
+  }
+}