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 028805bcdb1d2bb0d11387db165b7376579e5f60..51bc04571f75a4ccf05c3d080531a29fe35817d1 100644
--- a/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
+++ b/src/main/java/org/bukkit/plugin/PluginDescriptionFile.java
@@ -255,6 +255,20 @@ public final class PluginDescriptionFile implements io.papermc.paper.plugin.conf
     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 String foliaSupported;
+    private static final String FOLIA_SUPPORTED_KEY = "folia-supported";
+
+    /**
+     * Returns whether the plugin has been marked to be compatible with regionised threading as provided
+     * by Folia
+     */
+    public boolean isFoliaSupported() {
+        return this.foliaSupported != null && this.foliaSupported.equalsIgnoreCase("true");
+    }
+    // Folia end - block plugins not marked as supported
+
     // Paper start - oh my goddddd
     /**
      * Don't use this.
@@ -1238,6 +1252,11 @@ public final class PluginDescriptionFile implements io.papermc.paper.plugin.conf
         if (map.get("prefix") != null) {
             prefix = map.get("prefix").toString();
         }
+        // Folia start - block plugins not marked as supported
+        if (map.get(FOLIA_SUPPORTED_KEY) != null) {
+            foliaSupported = map.get(FOLIA_SUPPORTED_KEY).toString();
+        }
+        // Folia end - block plugins not marked as supported
     }
 
     @NotNull
@@ -1314,6 +1333,11 @@ public final class PluginDescriptionFile implements io.papermc.paper.plugin.conf
         if (prefix != null) {
             map.put("prefix", prefix);
         }
+        // Folia start - block plugins not marked as supported
+        if (foliaSupported != null) {
+            map.put(FOLIA_SUPPORTED_KEY, foliaSupported);
+        }
+        // Folia end - block plugins not marked as supported
 
         return map;
     }
diff --git a/src/main/java/org/bukkit/plugin/SimplePluginManager.java b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
index 800f954161886ca4f6332f8e0cbc4d4e8f9cbb74..e0026c938aa369d6d9797852324437456d3c4ed9 100644
--- a/src/main/java/org/bukkit/plugin/SimplePluginManager.java
+++ b/src/main/java/org/bukkit/plugin/SimplePluginManager.java
@@ -173,6 +173,12 @@ public final class SimplePluginManager implements PluginManager {
                     server.getLogger().log(Level.SEVERE, "Could not load '" + file.getPath() + "' in folder '" + directory.getPath() + "': uses the space-character (0x20) in its name");
                     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 '" + directory.getPath() + "'", ex);
                 continue;