Implement legacy material conversion

java/patchbukkit-test-plugin/src/main/java/org/patchbukkit/testplugin/DynamicTestProvider.java

@@ -0,0 +1,7 @@
+package org.patchbukkit.testplugin;
+
+import java.util.List;
+
+public interface DynamicTestProvider {
+    List<TestResult> runDynamicTests();
+}

java/patchbukkit-test-plugin/src/main/java/org/patchbukkit/testplugin/PatchBukkitTestPlugin.java

@@ -22,6 +22,7 @@ public void onEnable() {
         framework.registerSuite(new ConsoleSenderTests());
         framework.registerSuite(new UnsafeValuesTests());
         framework.registerSuite(new StubTests());
+        framework.registerSuite(new LegacyMaterialTests());
 
         // Set executor on the PluginCommand created by PatchBukkit's Rust side
         PbTestCommand cmd = new PbTestCommand(framework);

java/patchbukkit-test-plugin/src/main/java/org/patchbukkit/testplugin/TestCategory.java

@@ -10,5 +10,6 @@ public enum TestCategory {
     ENTITY,
     CONSOLE_SENDER,
     UNSAFE_VALUES,
-    STUBS
+    STUBS,
+    LEGACY_MATERIALS
 }

java/patchbukkit-test-plugin/src/main/java/org/patchbukkit/testplugin/TestFramework.java

@@ -40,16 +40,9 @@ public List<TestResult> runAll() {
     }
 
     public List<TestResult> runCategory(TestCategory category) {
-        List<TestResult> results = new ArrayList<>();
-        for (Object suite : suites) {
-            for (Method method : suite.getClass().getDeclaredMethods()) {
-                ConformanceTest ann = method.getAnnotation(ConformanceTest.class);
-                if (ann != null && ann.category() == category) {
-                    results.add(runTest(suite, method, ann));
-                }
-            }
-        }
-        return results;
+        return runAll().stream()
+                .filter(r -> r.category() == category)
+                .toList();
     }
 
     private List<TestResult> runSuite(Object suite) {
@@ -60,6 +53,9 @@ private List<TestResult> runSuite(Object suite) {
                 results.add(runTest(suite, method, ann));
             }
         }
+        if (suite instanceof DynamicTestProvider provider) {
+            results.addAll(provider.runDynamicTests());
+        }
         return results;
     }
 

java/patchbukkit-test-plugin/src/main/java/org/patchbukkit/testplugin/tests/LegacyMaterialTests.java

@@ -0,0 +1,58 @@
+package org.patchbukkit.testplugin.tests;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Material;
+import org.bukkit.material.MaterialData;
+import org.patchbukkit.testplugin.DynamicTestProvider;
+import org.patchbukkit.testplugin.TestCategory;
+import org.patchbukkit.testplugin.TestExpectation;
+import org.patchbukkit.testplugin.TestResult;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@SuppressWarnings("deprecation")
+public final class LegacyMaterialTests implements DynamicTestProvider {
+
+    @Override
+    public List<TestResult> runDynamicTests() {
+        List<TestResult> results = new ArrayList<>();
+
+        for (Material mat : Material.values()) {
+            if (!mat.isLegacy()) continue;
+            if (mat == Material.LEGACY_AIR) continue;
+
+            String name = mat.name();
+            try {
+                Material result = Bukkit.getUnsafe().fromLegacy(new MaterialData(mat, (byte) 0));
+                if (result != null && result != Material.AIR) {
+                    results.add(new TestResult(
+                        name + " -> " + result.name(),
+                        TestCategory.LEGACY_MATERIALS,
+                        TestExpectation.SHOULD_WORK,
+                        true,
+                        null
+                    ));
+                } else {
+                    results.add(new TestResult(
+                        name + " -> " + result,
+                        TestCategory.LEGACY_MATERIALS,
+                        TestExpectation.SHOULD_WORK,
+                        false,
+                        "Converted to " + result + " (expected non-AIR)"
+                    ));
+                }
+            } catch (Exception e) {
+                results.add(new TestResult(
+                    name + " -> ERROR",
+                    TestCategory.LEGACY_MATERIALS,
+                    TestExpectation.SHOULD_WORK,
+                    false,
+                    e.getClass().getSimpleName() + ": " + e.getMessage()
+                ));
+            }
+        }
+
+        return results;
+    }
+}