Folia/patches/api/0003-Require-plugins-to-be-explicitly-marked-as-Folia-sup.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Mon, 6 Mar 2023 13:14:06 -0800
Subject: [PATCH] Require plugins to be explicitly marked as Folia supported

Plugins must add "folia-supported: true" to their plugin.yml
otherwise the server will refuse to load them.

Since Folia is a major breakage for plugins, the vast majority
of plugins will not function correctly on Folia. To prevent
user confusion from this, we will refuse to load the plugin
and provide a log indicating why - which will be much
more helpful than some random error log caused by
a breakage.

diff --git a/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java b/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
index 0c9f4d1e9104fa6951114c1f9ec954dfcc749196..fc11577083672f127335613459436167d339efa4 100644
--- a/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
+++ b/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
@@ -254,6 +254,17 @@ public final class PluginDescriptionFile {
     private Set<PluginAwareness> awareness = ImmutableSet.of();
     private String apiVersion = null;
     private List<String> libraries = ImmutableList.of();
+    // Folia start - block plugins not marked as supported
+    private boolean foliaSupported;
+
+    /**
+     * Returns whether the plugin has been marked to be compatible with regionised threading as provided
+     * by Folia
+     */
+    public boolean isFoliaSupported() {
+        return foliaSupported;
+    }
+    // Folia end - block plugins not marked as supported
 
     public PluginDescriptionFile(@NotNull final InputStream stream) throws InvalidDescriptionException {
         loadMap(asMap(YAML.get().load(stream)));
@@ -1173,6 +1184,11 @@ public final class PluginDescriptionFile {
         if (map.get("prefix") != null) {
             prefix = map.get("prefix").toString();
         }
+        // Folia start - block plugins not marked as supported
+        if (map.get("folia-supported") != null) {
+            foliaSupported = map.get("folia-supported").toString().equalsIgnoreCase("true");
+        }
+        // Folia end - block plugins not marked as supported
     }
 
     @NotNull
diff --git a/src/main/java/org/bukkit/plugin/SimplePluginManager.java b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
index 499dc8309a16b33d16b57b433c3c5b4330323717..25f228e616d1f5475a06bf3eeb2cf1cf6b6ed352 100644
--- a/src/main/java/org/bukkit/plugin/SimplePluginManager.java
+++ b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
@@ -163,6 +163,12 @@ public final class SimplePluginManager implements PluginManager {
                     server.getLogger().log(Level.SEVERE, "Could not load '" + file.getPath() + "' in folder '" + file.getParentFile().getPath() + "': uses the space-character (0x20) in its name"); // Paper
                     continue;
                 }
+                // Folia start - block plugins not marked as supported
+                if (!description.isFoliaSupported()) {
+                    server.getLogger().log(Level.SEVERE, "Could not load plugin '" + name + "' as it is not marked as supporting Folia!");
+                    continue;
+                }
+                // Folia end - block plugins not marked as supported
             } catch (InvalidDescriptionException ex) {
                 server.getLogger().log(Level.SEVERE, "Could not load '" + file.getPath() + "' in folder '" + file.getParentFile().getPath() + "'", ex); // Paper
                 continue;