"Duplicate key" with fields that are equally named

[MrEAlderson]

I am using ProGuard to obfuscate a plugin that I maintain, together with a -overloadaggressively setting that I got from a template back then. Today I learned what that actually does and that it is apparently fully legitimate to have fields be equally named on the bytecode level (source):

Which leads to the following error:

[23:05:23 ERROR]: [PluginRemapper] Encountered exception remapping plugins
java.util.concurrent.CompletionException: java.lang.RuntimeException: Failed to remap plugin jar 'plugins\bedwars.jar'
        at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:315) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:320) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:649) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:482) ~[?:?]
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) ~[?:?]
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) ~[?:?]
        at java.base/java.lang.Thread.run(Thread.java:1583) ~[?:?]
Caused by: java.lang.RuntimeException: Failed to remap plugin jar 'plugins\bedwars.jar'
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:358) ~[paper-1.20.6.jar:1.20.6-130-5d8e53d]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.lang.RuntimeException: Failed to execute task de/marcely/bedwars/s
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:56) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.AsyncHelper.consumeAll(AsyncHelper.java:36) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:177) ~[paper-1.20.6.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:95) ~[paper-1.20.6.jar:?]
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:355) ~[paper-1.20.6.jar:1.20.6-130-5d8e53d]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.util.concurrent.ExecutionException: java.lang.IllegalStateException: Duplicate key a (attempted merging values private final de/marcely/bedwars/s/a Lde/marcely/bedwars/q; and private final de/marcely/bedwars/s/a Lde/marcely/bedwars/r;)
        at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:?]
        at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[?:?]
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:52) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.AsyncHelper.consumeAll(AsyncHelper.java:36) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:177) ~[paper-1.20.6.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:95) ~[paper-1.20.6.jar:?]
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:355) ~[paper-1.20.6.jar:1.20.6-130-5d8e53d]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.lang.IllegalStateException: Duplicate key a (attempted merging values private final de/marcely/bedwars/s/a Lde/marcely/bedwars/q; and private final de/marcely/bedwars/s/a Lde/marcely/bedwars/r;)
        at java.base/java.util.stream.Collectors.duplicateKeyException(Collectors.java:135) ~[?:?]
        at java.base/java.util.stream.Collectors.lambda$uniqKeysMapAccumulator$1(Collectors.java:182) ~[?:?]
        at java.base/java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169) ~[?:?]
        at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197) ~[?:?]
        at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1708) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499) ~[?:?]
        at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[?:?]
        at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682) ~[?:?]
        at net.neoforged.art.internal.ClassProviderImpl$ClassInfo.<init>(ClassProviderImpl.java:122) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.ClassProviderBuilderImpl.lambda$addClass$1(ClassProviderBuilderImpl.java:64) ~[AutoRenamingTool-2.0.3.jar:?]
        at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1708) ~[?:?]
        at net.neoforged.art.internal.ClassProviderBuilderImpl.addClass(ClassProviderBuilderImpl.java:64) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.lambda$run$2(RenamerImpl.java:178) ~[paper-1.20.6.jar:?]
        at net.neoforged.art.internal.AsyncHelper.lambda$null$0(AsyncHelper.java:33) ~[AutoRenamingTool-2.0.3.jar:?]
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317) ~[?:?]
        ... 3 more

Related PR: #9

[DerMistkaefer]

We upgrading to paper 1.21 and now getting the same error in PlayerChunkMap

[22:52:30 ERROR]: [PluginRemapper] Encountered exception remapping plugins
java.util.concurrent.CompletionException: java.lang.RuntimeException: Failed to remap plugin jar 'plugins\lobby-spigot.jar'
        at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:315) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:320) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:649) ~[?:?]
        at java.base/java.util.concurrent.CompletableFuture$Completion.run(CompletableFuture.java:482) ~[?:?]
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144) ~[?:?]
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642) ~[?:?]
        at java.base/java.lang.Thread.run(Thread.java:1583) ~[?:?]
Caused by: java.lang.RuntimeException: Failed to remap plugin jar 'plugins\lobby-spigot.jar'
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:358) ~[paper-1.21.jar:1.21-DEV-167961e]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.lang.RuntimeException: Failed to execute task de/cytooxien/lobby/spigot/phantom/entityhider/EntityHiderPacketListener.class
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:56) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:41) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:184) ~[paper-1.21.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:95) ~[paper-1.21.jar:?]
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:355) ~[paper-1.21.jar:1.21-DEV-167961e]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.util.concurrent.ExecutionException: java.lang.IllegalStateException: Duplicate key F (attempted merging values private final net/minecraft/server/level/PlayerChunkMap/F Lnet/minecraft/world/level/entity/ChunkStatusUpdateListener; and public final net/minecraft/server/level/PlayerChunkMap/F Lnet/minecraft/server/level/PlayerChunkMap$ChunkDistanceManager;)
        at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:?]
        at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[?:?]
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:52) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.AsyncHelper.invokeAll(AsyncHelper.java:41) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:184) ~[paper-1.21.jar:?]
        at net.neoforged.art.internal.RenamerImpl.run(RenamerImpl.java:95) ~[paper-1.21.jar:?]
        at io.papermc.paper.pluginremap.PluginRemapper.lambda$remap$7(PluginRemapper.java:355) ~[paper-1.21.jar:1.21-DEV-167961e]
        at java.base/java.util.concurrent.CompletableFuture$UniApply.tryFire(CompletableFuture.java:646) ~[?:?]
        ... 4 more
Caused by: java.lang.IllegalStateException: Duplicate key F (attempted merging values private final net/minecraft/server/level/PlayerChunkMap/F Lnet/minecraft/world/level/entity/ChunkStatusUpdateListener; and public final net/minecraft/server/level/PlayerChunkMap/F Lnet/minecraft/server/level/PlayerChunkMap$ChunkDistanceManager;)
        at java.base/java.util.stream.Collectors.duplicateKeyException(Collectors.java:135) ~[?:?]
        at java.base/java.util.stream.Collectors.lambda$uniqKeysMapAccumulator$1(Collectors.java:182) ~[?:?]
        at java.base/java.util.stream.ReduceOps$3ReducingSink.accept(ReduceOps.java:169) ~[?:?]
        at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197) ~[?:?]
        at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1708) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499) ~[?:?]
        at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:921) ~[?:?]
        at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[?:?]
        at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:682) ~[?:?]
        at net.neoforged.art.internal.ClassProviderImpl$ClassInfo.<init>(ClassProviderImpl.java:122) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.ClassProviderImpl.computeClassInfo(ClassProviderImpl.java:80) ~[AutoRenamingTool-2.0.3.jar:?]
        at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1740) ~[?:?]
        at net.neoforged.art.internal.ClassProviderImpl.getClass(ClassProviderImpl.java:66) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.SortedClassProvider.computeClassInfo(SortedClassProvider.java:34) ~[AutoRenamingTool-2.0.3.jar:?]
        at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1740) ~[?:?]
        at net.neoforged.art.internal.SortedClassProvider.getClass(SortedClassProvider.java:29) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.EnhancedRemapper.computeClass(EnhancedRemapper.java:143) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.EnhancedRemapper.getClass(EnhancedRemapper.java:126) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.EnhancedRemapper.map(EnhancedRemapper.java:88) ~[AutoRenamingTool-2.0.3.jar:?]
        at org.objectweb.asm.commons.Remapper.mapType(Remapper.java:78) ~[asm-commons-9.7.jar:9.7]
        at org.objectweb.asm.commons.Remapper.mapType(Remapper.java:99) ~[asm-commons-9.7.jar:9.7]
        at org.objectweb.asm.commons.ClassRemapper.visitInnerClass(ClassRemapper.java:201) ~[asm-commons-9.7.jar:9.7]
        at org.objectweb.asm.ClassReader.accept(ClassReader.java:718) ~[asm-9.7.jar:9.7]
        at org.objectweb.asm.ClassReader.accept(ClassReader.java:425) ~[asm-9.7.jar:9.7]
        at net.neoforged.art.internal.RenamingTransformer.process(RenamingTransformer.java:50) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.EntryImpl$ClassEntry.process(EntryImpl.java:58) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.EntryImpl$ClassEntry.process(EntryImpl.java:36) ~[AutoRenamingTool-2.0.3.jar:?]
        at net.neoforged.art.internal.RenamerImpl.processEntry(RenamerImpl.java:288) ~[paper-1.21.jar:?]
        at net.neoforged.art.internal.AsyncHelper.lambda$null$2(AsyncHelper.java:40) ~[AutoRenamingTool-2.0.3.jar:?]
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317) ~[?:?]
        ... 3 more
```

[jpenilla]

@DerMistkaefer
That is a fixed issue which was due to the mappings patch not getting updated
PaperMC/Paper@de8220c