Add new Enigma IO which only sorts inner classes lexicographically

Enigma 2.4.0 changed its writing system  to use the mapping-io library.

The library differs in how it writes inner classes. Previously, inner
class sorting worked by first sorting based on enclosing classes first,
then by length and then lexicographically. Now, inner class sorting is
solely lexicographically, without regard to length.

To allow for compatibility with Enigma versions that do not yet use
mapping-io, the existing Enigma IO retains its behavior, and new Enigma
IO instances, `ENIGMA_EXPLODED_LENGTH_SORT` and
`ENIGMA_EXPLODED_LEXICOGRAPHIC_SORT`, are introduced which express the
original behavior and the new behavior respectively.

`ENIGMA_EXPLODED_LEXICOGRAPHIC_SORT` can be specified for the data
directories using the `compass` extension as usual.

Author: sciwhiz12

src/main/java/org/parchmentmc/compass/storage/io/MappingIOFormat.java

@@ -9,7 +9,9 @@
 public enum MappingIOFormat implements MappingDataIO {
     MDC_SINGLE(true, SingleFileDataIO.INSTANCE),
     MDC_EXPLODED(false, ExplodedDataIO.INSTANCE),
-    ENIGMA_EXPLODED(false, EnigmaFormattedExplodedIO.INSTANCE);
+    ENIGMA_EXPLODED(false, EnigmaFormattedExplodedIO.LENGTH_SORT_INSTANCE),
+    ENIGMA_EXPLODED_LENGTH_SORT(false, EnigmaFormattedExplodedIO.LENGTH_SORT_INSTANCE),
+    ENIGMA_EXPLODED_LEXICOGRAPHIC_SORT(false, EnigmaFormattedExplodedIO.LEXICOGRAPHIC_SORT_INSTANCE);
 
     private final boolean fileBased;
     private final MappingDataIO dataIO;

src/main/java/org/parchmentmc/compass/storage/io/enigma/EnigmaFormattedExplodedIO.java

@@ -22,6 +22,7 @@
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.*;
 import java.util.function.Function;
+import java.util.function.Supplier;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -30,8 +31,10 @@
 import static org.parchmentmc.feather.mapping.MappingDataContainer.ClassData;
 
 public class EnigmaFormattedExplodedIO implements MappingDataIO {
-    public static final EnigmaFormattedExplodedIO INSTANCE = new EnigmaFormattedExplodedIO(JSONUtil.MOSHI,
-            "    ", "mapping");
+    public static final EnigmaFormattedExplodedIO LENGTH_SORT_INSTANCE = new EnigmaFormattedExplodedIO(JSONUtil.MOSHI,
+            "    ", "mapping", true);
+    public static final EnigmaFormattedExplodedIO LEXICOGRAPHIC_SORT_INSTANCE = new EnigmaFormattedExplodedIO(JSONUtil.MOSHI,
+            "    ", "mapping", false);
 
     static final CharMatcher DOLLAR_SIGN = CharMatcher.is('$');
     static final String DOLLAR_SIGN_REGEX = "\\$";
@@ -54,11 +57,15 @@ public class EnigmaFormattedExplodedIO implements MappingDataIO {
     private final Moshi moshi;
     private final String jsonIndent;
     private final String extension;
+    // Whether to manually sort inner classes by inner class name length then lexicographically
+    // If false, then sorting is lexicographically by the entire inner class FQN
+    private final boolean lengthSort;
 
-    public EnigmaFormattedExplodedIO(Moshi moshi, String jsonIndent, String extension) {
+    public EnigmaFormattedExplodedIO(Moshi moshi, String jsonIndent, String extension, boolean lengthSort) {
         this.moshi = moshi;
         this.jsonIndent = jsonIndent;
         this.extension = extension;
+        this.lengthSort = lengthSort;
     }
 
     @Override
@@ -79,11 +86,14 @@ public void write(VersionedMappingDataContainer data, Path base) throws IOExcept
         }
 
         // Group classes by their outermost classes (via `$` matching)
+        final Supplier<Set<String>> setCreator = lengthSort
+                ? () -> new TreeSet<>(EnigmaFormattedExplodedIO::compareClassNames)
+                : TreeSet::new;
         final Map<String, Set<String>> outerClassesToClasses = data.getClasses().stream()
                 .map(ClassData::getName)
                 .sorted()
                 .collect(Collectors.groupingBy(EnigmaWriter::stripToOuter,
-                        Collectors.toCollection(() -> new TreeSet<>(EnigmaFormattedExplodedIO::compareClassNames))));
+                        Collectors.toCollection(setCreator)));
 
         Set<String> visited = new HashSet<>();