#1467 Rearrange old keys migration so no entries get lost

- 'error' was an old entry but now we have multiple entries under 'error' (which is now a section), so we need to ensure that we migrate the old 'error' entry before the migration sets anything under that path

src/test/java/tools/messages/MessagesFileWriter.java

@@ -25,7 +25,7 @@ import java.util.regex.Pattern;
  * were at the top of the file and to separate comments by new lines (which ConfigMe
  * currently doesn't support).
  */
-public class MessagesFileWriter {
+public final class MessagesFileWriter {
 
     /** Marker used inside a text to signal that it should be a comment later on. */
     private static final String COMMENT_MARKER = "::COMMENT::";
@@ -52,7 +52,7 @@ public class MessagesFileWriter {
 
         // Create property resource with new defaults, save with ConfigMe for proper sections & comments
         PropertyResource resource = createPropertyResourceWithCommentEntries();
-        new SettingsManager(resource, null, MessageUpdater.CONFIGURATION_DATA).save();
+        new SettingsManager(resource, null, MessageUpdater.getConfigurationData()).save();
 
         // Go through the newly saved file and replace texts with comment marker to actual YAML comments
         // and add initial comments back to the file
@@ -89,7 +89,7 @@ public class MessagesFileWriter {
      * @return the first comment generated by ConfigMe (comment of the first root path)
      */
     private static String getFirstCommentByConfigMe() {
-        ConfigurationData configurationData = MessageUpdater.CONFIGURATION_DATA;
+        ConfigurationData configurationData = MessageUpdater.getConfigurationData();
         String firstRootPath = configurationData.getProperties().get(0).getPath().split("\\.")[0];
         return "# " + configurationData.getCommentsForSection(firstRootPath)[0];
     }
@@ -100,7 +100,7 @@ public class MessagesFileWriter {
      */
     private PropertyResource createPropertyResourceWithCommentEntries() {
         YamlFileResource resource = new MigraterYamlFileResource(file);
-        for (Property<?> property : MessageUpdater.CONFIGURATION_DATA.getProperties()) {
+        for (Property<?> property : MessageUpdater.getConfigurationData().getProperties()) {
             String text = resource.getString(property.getPath());
             if (text == null) {
                 resource.setValue(property.getPath(), COMMENT_MARKER + defaultFile.getString(property.getPath()));
@@ -132,6 +132,7 @@ public class MessagesFileWriter {
                 newLines.add(line);
             }
         }
+        newLines.add(""); // Makes sure file ends with new line
 
         FileIoUtils.writeToFile(file.toPath(), String.join("\n", newLines));
     }