Abstract Messages into two layers; move to new 'output' package

- Abstract Messages into two layers: the top layer 'Messages' is how Messages can be retrieved and sent as before. In the background, package-private, MessagesManager actually does the file read and worries about I/O while Messages takes care of higher-level things (such as joining two lines or checking the current language).

src/test/java/fr/xephi/authme/output/MessageKeyTest.java

@@ -0,0 +1,33 @@
+package fr.xephi.authme.output;
+
+import fr.xephi.authme.util.StringUtils;
+import org.junit.Test;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static org.junit.Assert.fail;
+
+/**
+ * Test for {@link MessageKey}.
+ */
+public class MessageKeyTest {
+
+    @Test
+    public void shouldHaveUniqueMessageKeys() {
+        // given
+        MessageKey[] messageKeys = MessageKey.values();
+        Set<String> keys = new HashSet<>();
+
+        // when / then
+        for (MessageKey messageKey : messageKeys) {
+            String key = messageKey.getKey();
+            if (keys.contains(key)) {
+                fail("Found key '" + messageKey.getKey() + "' twice!");
+            } else if (StringUtils.isEmpty(key)) {
+                fail("Key for message key '" + messageKey + "' is empty");
+            }
+            keys.add(key);
+        }
+    }
+}

src/test/java/fr/xephi/authme/output/MessagesIntegrationTest.java

@@ -0,0 +1,140 @@
+package fr.xephi.authme.output;
+
+import fr.xephi.authme.settings.Settings;
+import fr.xephi.authme.util.WrapperMock;
+import org.bukkit.entity.Player;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+import java.io.File;
+import java.net.URL;
+
+import static org.hamcrest.Matchers.arrayWithSize;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.startsWith;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Test for {@link Messages}.
+ */
+public class MessagesIntegrationTest {
+
+    private static final String YML_TEST_FILE = "messages_test.yml";
+    private Messages messages;
+
+    /**
+     * Loads the messages in the file {@code messages_test.yml} in the test resources folder.
+     * The file does not contain all messages defined in {@link MessageKey} and its contents
+     * reflect various test cases -- not what the keys stand for.
+     */
+    @Before
+    public void setUpMessages() {
+        WrapperMock.createInstance();
+
+        Settings.messagesLanguage = "en";
+        URL url = getClass().getClassLoader().getResource(YML_TEST_FILE);
+        if (url == null) {
+            throw new RuntimeException("File '" + YML_TEST_FILE + "' could not be loaded");
+        }
+
+        Settings.messageFile = new File(url.getFile());
+        Settings.messagesLanguage = "en";
+        messages = Messages.getInstance();
+    }
+
+    @Test
+    public void shouldLoadMessageAndSplitAtNewLines() {
+        // given
+        MessageKey key = MessageKey.UNKNOWN_USER;
+
+        // when
+        String[] message = messages.retrieve(key);
+
+        // then
+        String[] lines = new String[]{"This test message", "includes", "some new lines"};
+        assertThat(message, equalTo(lines));
+    }
+
+    @Test
+    public void shouldLoadMessageAsStringWithNewLines() {
+        // given
+        MessageKey key = MessageKey.UNKNOWN_USER;
+
+        // when
+        String message = messages.retrieveSingle(key);
+
+        // then
+        assertThat(message, equalTo("This test message\nincludes\nsome new lines"));
+    }
+
+    @Test
+    public void shouldFormatColorCodes() {
+        // given
+        MessageKey key = MessageKey.UNSAFE_QUIT_LOCATION;
+
+        // when
+        String[] message = messages.retrieve(key);
+
+        // then
+        assertThat(message, arrayWithSize(1));
+        assertThat(message[0], equalTo("§cHere we have§bdefined some colors §dand some other §lthings"));
+    }
+
+    @Test
+    public void shouldRetainApostrophes() {
+        // given
+        MessageKey key = MessageKey.NOT_LOGGED_IN;
+
+        // when
+        String[] message = messages.retrieve(key);
+
+        // then
+        assertThat(message, arrayWithSize(1));
+        assertThat(message[0], equalTo("Apostrophes ' should be loaded correctly, don't you think?"));
+    }
+
+    @Test
+    public void shouldReturnErrorForUnknownCode() {
+        // given
+        // The following is a key that is not defined in the test file
+        MessageKey key = MessageKey.UNREGISTERED_SUCCESS;
+
+        // when
+        String[] message = messages.retrieve(key);
+
+        // then
+        assertThat(message, arrayWithSize(1));
+        assertThat(message[0], startsWith("Error getting message with key '"));
+    }
+
+    @Test
+    public void shouldSendMessageToPlayer() {
+        // given
+        MessageKey key = MessageKey.UNSAFE_QUIT_LOCATION;
+        Player player = Mockito.mock(Player.class);
+
+        // when
+        messages.send(player, key);
+
+        // then
+        verify(player).sendMessage("§cHere we have§bdefined some colors §dand some other §lthings");
+    }
+
+    @Test
+    public void shouldSendMultiLineMessageToPlayer() {
+        // given
+        MessageKey key = MessageKey.UNKNOWN_USER;
+        Player player = Mockito.mock(Player.class);
+
+        // when
+        messages.send(player, key);
+
+        // then
+        String[] lines = new String[]{"This test message", "includes", "some new lines"};
+        for (String line : lines) {
+            verify(player).sendMessage(line);
+        }
+    }
+}