Migrate ConversationList to paging library and apply abstractions to conversation.

app/src/test/java/org/thoughtcrime/securesms/util/DeferredTest.java

@@ -0,0 +1,74 @@
+package org.thoughtcrime.securesms.util;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+public class DeferredTest {
+
+  private int accumulator = 0;
+
+  private final Runnable incrementAccumulator = () -> accumulator++;
+  private final Deferred testSubject          = new Deferred();
+
+  @Test
+  public void givenANullRunnable_whenISetDeferredToFalse_thenIDoNotThrow() {
+    // GIVEN
+    testSubject.defer(null);
+
+    // WHEN
+    testSubject.setDeferred(false);
+  }
+
+  @Test
+  public void givenADeferredRunnable_whenIDeferADifferentRunnableAndSetDeferredFalse_thenIExpectOnlySecondRunnableToExecute() {
+    // GIVEN
+    testSubject.defer(() -> fail("This runnable should never execute"));
+
+    // WHEN
+    testSubject.defer(incrementAccumulator);
+    testSubject.setDeferred(false);
+
+    // THEN
+    assertEquals(1, accumulator);
+  }
+
+  @Test
+  public void givenSetDeferredFalse_whenIDeferARunnable_thenIExecuteImmediately() {
+    // GIVEN
+    testSubject.setDeferred(false);
+
+    // WHEN
+    testSubject.defer(incrementAccumulator);
+
+    // THEN
+    assertEquals(1, accumulator);
+  }
+
+  @Test
+  public void givenSetDeferredFalse_whenISetToTrueAndDeferRunnable_thenIDoNotExecute() {
+    // GIVEN
+    testSubject.setDeferred(false);
+
+    // WHEN
+    testSubject.setDeferred(true);
+    testSubject.defer(incrementAccumulator);
+
+    // THEN
+    assertEquals(0, accumulator);
+  }
+
+  @Test
+  public void givenDeferredRunnable_whenIDeferNullAndSetDeferredFalse_thenIDoNotExecute() {
+    // GIVEN
+    testSubject.defer(incrementAccumulator);
+
+    // WHEN
+    testSubject.defer(null);
+    testSubject.setDeferred(true);
+
+    // THEN
+    assertEquals(0, accumulator);
+  }
+}