Make the message for ModLoadingException show a translated (english) …

…message. (#147)

loader/src/main/java/net/neoforged/fml/ModLoadingException.java

@@ -6,7 +6,7 @@
 package net.neoforged.fml;
 
 import java.util.List;
-import java.util.stream.Collectors;
+import net.neoforged.fml.i18n.FMLTranslations;
 
 public class ModLoadingException extends RuntimeException {
     private final List<ModLoadingIssue> issues;
@@ -25,7 +25,36 @@ public List<ModLoadingIssue> getIssues() {
 
     @Override
     public String getMessage() {
-        return "Loading errors encountered: " + this.issues.stream().map(ModLoadingIssue::translationKey)
-                .collect(Collectors.joining(",\n\t", "[\n\t", "\n]"));
+        var result = new StringBuilder();
+        var errors = this.issues.stream().filter(i -> i.severity() == ModLoadingIssue.Severity.ERROR).toList();
+        if (!errors.isEmpty()) {
+            result.append("Loading errors encountered:\n");
+            for (var error : errors) {
+                appendIssue(error, result);
+            }
+        }
+        var warnings = this.issues.stream().filter(i -> i.severity() == ModLoadingIssue.Severity.WARNING).toList();
+        if (!warnings.isEmpty()) {
+            result.append("Loading warnings encountered:\n");
+            for (var warning : warnings) {
+                appendIssue(warning, result);
+            }
+        }
+        return result.toString();
+    }
+
+    private void appendIssue(ModLoadingIssue issue, StringBuilder result) {
+        String translation;
+        try {
+            translation = FMLTranslations.stripControlCodes(FMLTranslations.translateIssueEnglish(issue));
+        } catch (Exception e) {
+            // Fall back to *something* readable in case the translation fails
+            translation = issue.toString();
+        }
+
+        // Poor mans indentation
+        translation = translation.replace("\n", "\n\t  ");
+
+        result.append("\t- ").append(translation).append("\n");
     }
 }

loader/src/main/java/net/neoforged/fml/i18n/FMLTranslations.java

@@ -125,7 +125,17 @@ public static String parseFormat(String format, final Object... args) {
         return extendedMessageFormat.format(args);
     }
 
+    public static String translateIssueEnglish(ModLoadingIssue issue) {
+        var args = getTranslationArgs(issue);
+        return parseEnglishMessage(issue.translationKey(), args);
+    }
+
     public static String translateIssue(ModLoadingIssue issue) {
+        var args = getTranslationArgs(issue);
+        return parseMessage(issue.translationKey(), args);
+    }
+
+    private static Object[] getTranslationArgs(ModLoadingIssue issue) {
         var args = new ArrayList<>(3 + issue.translationArgs().size());
 
         var modInfo = issue.affectedMod();
@@ -144,13 +154,13 @@ public static String translateIssue(ModLoadingIssue issue) {
 
         args.replaceAll(FMLTranslations::formatArg);
 
-        return parseMessage(issue.translationKey(), args.toArray(Object[]::new));
+        return args.toArray(Object[]::new);
     }
 
     private static Object formatArg(Object arg) {
         if (arg instanceof Path path) {
             var gameDir = FMLLoader.getGamePath();
-            if (path.startsWith(gameDir)) {
+            if (gameDir != null && path.startsWith(gameDir)) {
                 return gameDir.relativize(path).toString();
             } else {
                 return path.toString();

loader/src/test/java/net/neoforged/fml/ModLoadingExceptionTest.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) NeoForged and contributors
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.neoforged.fml;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.List;
+import org.junit.jupiter.api.Test;
+
+class ModLoadingExceptionTest {
+    @Test
+    void getMessage() {
+        var w = ModLoadingIssue.warning("fml.modloading.brokenfile.unknown", "XXXX");
+        var e1 = ModLoadingIssue.error("fml.modloading.brokenfile", "YYYY");
+        var e2 = ModLoadingIssue.error("Some untranslated text\nwhich has newlines in it");
+
+        var message = new ModLoadingException(List.of(w, e1, e2)).getMessage();
+        assertEquals("""
+                Loading errors encountered:
+                \t- File YYYY is not a valid mod file
+                \t- Some untranslated text
+                \t  which has newlines in it
+                Loading warnings encountered:
+                \t- File XXXX is not a valid mod file
+                """, message);
+    }
+}