From 47650100837178e2852bdb50d8c9c6f0cc0bb2e0 Mon Sep 17 00:00:00 2001
From: Jason Penilla <11360596+jpenilla@users.noreply.github.com>
Date: Wed, 28 May 2025 12:33:25 -0700
Subject: [PATCH] Improve error messages when PluginRemapper fails to
 initialize (#12598)

---
 .../paper/pluginremap/PluginRemapper.java     |  6 ++++-
 .../pluginremap/RemappedPluginIndex.java      | 25 +++++++++++--------
 2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/paper-server/src/main/java/io/papermc/paper/pluginremap/PluginRemapper.java b/paper-server/src/main/java/io/papermc/paper/pluginremap/PluginRemapper.java
index 28857d0c9..fbad4a224 100644
--- a/paper-server/src/main/java/io/papermc/paper/pluginremap/PluginRemapper.java
+++ b/paper-server/src/main/java/io/papermc/paper/pluginremap/PluginRemapper.java
@@ -75,7 +75,11 @@ public final class PluginRemapper {
             return null;
         }
 
-        return new PluginRemapper(pluginsDir);
+        try {
+            return new PluginRemapper(pluginsDir);
+        } catch (final Exception e) {
+            throw new RuntimeException("Failed to create PluginRemapper, try deleting the '" + pluginsDir.resolve(PAPER_REMAPPED) + "' directory", e);
+        }
     }
 
     public void shutdown() {
diff --git a/paper-server/src/main/java/io/papermc/paper/pluginremap/RemappedPluginIndex.java b/paper-server/src/main/java/io/papermc/paper/pluginremap/RemappedPluginIndex.java
index 86fc60452..1a2e8902c 100644
--- a/paper-server/src/main/java/io/papermc/paper/pluginremap/RemappedPluginIndex.java
+++ b/paper-server/src/main/java/io/papermc/paper/pluginremap/RemappedPluginIndex.java
@@ -8,6 +8,7 @@ import io.papermc.paper.util.MappingEnvironment;
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -52,32 +53,35 @@ class RemappedPluginIndex {
             try {
                 Files.createDirectories(this.dir);
             } catch (final IOException ex) {
-                throw new RuntimeException(ex);
+                throw new UncheckedIOException(ex);
             }
         }
 
         this.indexFile = dir.resolve(INDEX_FILE_NAME);
         if (Files.isRegularFile(this.indexFile)) {
-            try {
-                this.state = this.readIndex();
-            } catch (final IOException e) {
-                throw new RuntimeException(e);
-            }
+            this.state = this.readIndex();
         } else {
             this.state = new State();
         }
     }
 
-    private State readIndex() throws IOException {
+    private State readIndex() {
         final State state;
         try (final BufferedReader reader = Files.newBufferedReader(this.indexFile)) {
             state = GSON.fromJson(reader, State.class);
+        } catch (final Exception ex) {
+            throw new RuntimeException("Failed to read index file '" + this.indexFile + "'", ex);
         }
 
         // If mappings have changed, delete all cached files and create a new index
         if (!state.mappingsHash.equals(MappingEnvironment.mappingsHash())) {
             for (final String fileName : state.hashes.values()) {
-                Files.deleteIfExists(this.dir.resolve(fileName));
+                final Path path = this.dir.resolve(fileName);
+                try  {
+                    Files.deleteIfExists(path);
+                } catch (final IOException ex) {
+                    throw new UncheckedIOException("Failed to delete no longer needed file '" + path + "'", ex);
+                }
             }
             return new State();
         }
@@ -111,10 +115,11 @@ class RemappedPluginIndex {
             }
 
             iterator.remove();
+            final Path filePath = this.dir.resolve(fileName);
             try {
-                Files.deleteIfExists(this.dir.resolve(fileName));
+                Files.deleteIfExists(filePath);
             } catch (final IOException ex) {
-                throw new RuntimeException(ex);
+                throw new UncheckedIOException("Failed to delete no longer needed file '" + filePath + "'", ex);
             }
         }