PS C:\Users\jls\Documents\projects\logstash> .\vendor\jruby\bin\jruby -S rake test:install-core
Invoking bundler install...

... < lots of output that looks healthy > ...

[plugin:install-core] Installing core plugins
Installing logstash-filter-clone, logstash-filter-cidr, logstash-filter-mutate, logstash-input-generator, logstash-input-stdin, logstash-input-tcp, logstash-output-stdout, logstash-filter-multiline
Unhandled Java exception: java.lang.NullPointerException
java.lang.NullPointerException: null
             getBytes at java/lang/String.java:928
               <init> at org/jruby/ast/SymbolNode.java:54
             asSymbol at org/jruby/parser/ParserSupport.java:975
              execute at org/jruby/parser/RubyParser.java:4286
              yyparse at org/jruby/parser/RubyParser.java:1677
              yyparse at org/jruby/parser/RubyParser.java:1568
                parse at org/jruby/parser/RubyParser.java:5365
                parse at org/jruby/parser/Parser.java:128
                parse at org/jruby/parser/Parser.java:77
            parseEval at org/jruby/Ruby.java:2722
            prepareIC at org/jruby/ir/interpreter/Interpreter.java:211
           evalCommon at org/jruby/ir/interpreter/Interpreter.java:167
           evalSimple at org/jruby/ir/interpreter/Interpreter.java:158
            evalUnder at org/jruby/RubyBasicObject.java:1917
         specificEval at org/jruby/RubyBasicObject.java:1842
      instance_eval19 at org/jruby/RubyBasicObject.java:1697
                 call at org/jruby/RubyBasicObject$INVOKER$i$instance_eval19.gen:-1
                 call at org/jruby/internal/runtime/methods/JavaMethod.java:328
                 call at org/jruby/runtime/callsite/CachingCallSite.java:161
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:314
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:83
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:179
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:165
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:200
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:338
                 call at org/jruby/runtime/callsite/CachingCallSite.java:163
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:314
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:77
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:144
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:130
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:192
                 call at org/jruby/runtime/callsite/CachingCallSite.java:129
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:339
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:77
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:144
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:130
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:192
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:318
                 call at org/jruby/runtime/callsite/CachingCallSite.java:131
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:339
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:83
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:179
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:165
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:200
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:338
                 call at org/jruby/runtime/callsite/CachingCallSite.java:163
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:314
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:77
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:144
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:130
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:192
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:318
                 call at org/jruby/runtime/callsite/CachingCallSite.java:131
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:339
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:83
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:179
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:165
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:200
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:338
                 call at org/jruby/runtime/callsite/CachingCallSite.java:163
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:314
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:77
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:144
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:130
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:192
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:318
                 call at org/jruby/runtime/callsite/CachingCallSite.java:131
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:339
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:83
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:179
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:165
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:200
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:338
                 call at org/jruby/runtime/callsite/CachingCallSite.java:163
          processCall at org/jruby/ir/interpreter/InterpreterEngine.java:314
            interpret at org/jruby/ir/interpreter/StartupInterpreterEngine.java:73
            interpret at org/jruby/ir/interpreter/InterpreterEngine.java:89
     INTERPRET_METHOD at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:214
                 call at org/jruby/internal/runtime/methods/MixedModeIRMethod.java:200
                 call at org/jruby/internal/runtime/methods/DynamicMethod.java:208
         cacheAndCall at org/jruby/runtime/callsite/CachingCallSite.java:358
                 call at org/jruby/runtime/callsite/CachingCallSite.java:195
    invokeOther67:run at C_3a_/Users/jls/Documents/projects/logstash/lib/pluginmanager/C:\Users\jls\Documents\projects\logstash\lib\pluginmanager\main.rb:48
               <main> at C:\Users\jls\Documents\projects\logstash\lib\pluginmanager\main.rb:48
  invokeWithArguments at java/lang/invoke/MethodHandle.java:636
                 load at org/jruby/ir/Compiler.java:95
            runScript at org/jruby/Ruby.java:827
          runNormally at org/jruby/Ruby.java:746
          runNormally at org/jruby/Ruby.java:764
          runFromMain at org/jruby/Ruby.java:577
        doRunFromMain at org/jruby/Main.java:417
          internalRun at org/jruby/Main.java:305
                  run at org/jruby/Main.java:232
                 main at org/jruby/Main.java:204

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