Tab completion after typing a period in a namespace triggers an NPE

[venantius]

Bit of an oddly specific bug, I know.

TL;DR - if I type clojure.co and then try to tab-complete, an NPE is triggered. Tab-completion works fine if I hit tab at cloj or at clojure.core/, but after that first period and before the slash I'll get NPE'd. I ran into this on a project and then was able to reproduce outside of a project context.

Now the expected behavior would be for tab completion to work the way it did when I hit tab at cloj, i.e. to show me the list of namespaces that are potential results for what I've typed so far.

Full command history and stacktrace:

▸ lein repl
nREPL server started on port 55883 on host 127.0.0.1 - nrepl://127.0.0.1:55883
REPL-y 0.3.7, nREPL 0.2.12
Clojure 1.8.0
Java HotSpot(TM) 64-Bit Server VM 9.0.1+11
    Docs: (doc function-name-here)
          (find-doc "part-of-name-here")
  Source: (source function-name-here)
 Javadoc: (javadoc java-object-or-class-here)
    Exit: Control+D or (exit) or (quit)
 Results: Stored in vars *1, *2, *3, an exception in *e

user=> clojure.corNullPointerException   complete.core/fn--632/iter--624--633/fn--634 (core.clj:66)


CompilerException java.lang.ClassNotFoundException: clojure.cor, compiling:(null:0:0)
user=> (pst)
clojure.lang.Compiler$CompilerException: java.lang.ClassNotFoundException: clojure.cor, compiling:(null:0:0)
                                Compiler.java:6688 clojure.lang.Compiler.analyze
                                Compiler.java:6625 clojure.lang.Compiler.analyze
                                Compiler.java:6931 clojure.lang.Compiler.eval
                                Compiler.java:6890 clojure.lang.Compiler.eval
                                     core.clj:3105 clojure.core/eval
                                     core.clj:3101 clojure.core/eval
                                      main.clj:240 clojure.main/repl[fn]
                                      main.clj:240 clojure.main/repl[fn]
                                      main.clj:258 clojure.main/repl[fn]
                                      main.clj:258 clojure.main/repl
                                      main.clj:174 clojure.main/repl
                                  RestFn.java:1523 clojure.lang.RestFn.invoke
                         interruptible_eval.clj:87 clojure.tools.nrepl.middleware.interruptible-eval/evaluate[fn]
                                      AFn.java:152 clojure.lang.AFn.applyToHelper
                                      AFn.java:144 clojure.lang.AFn.applyTo
                                      core.clj:646 clojure.core/apply
                                     core.clj:1881 clojure.core/with-bindings*
                                     core.clj:1881 clojure.core/with-bindings*
                                   RestFn.java:425 clojure.lang.RestFn.invoke
                         interruptible_eval.clj:85 clojure.tools.nrepl.middleware.interruptible-eval/evaluate
                         interruptible_eval.clj:55 clojure.tools.nrepl.middleware.interruptible-eval/evaluate
                        interruptible_eval.clj:224 clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval[fn]
                        interruptible_eval.clj:192 clojure.tools.nrepl.middleware.interruptible-eval/run-next[fn]
                                       AFn.java:22 clojure.lang.AFn.run
                      ThreadPoolExecutor.java:1167 java.util.concurrent.ThreadPoolExecutor.runWorker
                       ThreadPoolExecutor.java:641 java.util.concurrent.ThreadPoolExecutor$Worker.run
                                   Thread.java:844 java.lang.Thread.run
Caused by: java.lang.ClassNotFoundException: clojure.cor
                           URLClassLoader.java:466 java.net.URLClassLoader.findClass
                        DynamicClassLoader.java:69 clojure.lang.DynamicClassLoader.findClass
                              ClassLoader.java:563 java.lang.ClassLoader.loadClass
                        DynamicClassLoader.java:77 clojure.lang.DynamicClassLoader.loadClass
                              ClassLoader.java:496 java.lang.ClassLoader.loadClass
                                  (Unknown Source) java.lang.Class.forName0
                                    Class.java:375 java.lang.Class.forName
                                      RT.java:2168 clojure.lang.RT.classForName
                                      RT.java:2177 clojure.lang.RT.classForName
                                Compiler.java:7145 clojure.lang.Compiler.resolveIn
                                Compiler.java:7108 clojure.lang.Compiler.resolve
                                Compiler.java:7069 clojure.lang.Compiler.analyzeSymbol
                                Compiler.java:6648 clojure.lang.Compiler.analyze
nil

Originally reported as a Leiningen issue here: technomancy/leiningen#2380

[venantius]

This seems to be an issue with JDK 9 specifically - the above works fine on Java 1.8.0 patch 31.

[tirkarthi]

A test case to work on. As in the below repl "sun.boot.class.path" "java.ext.dirs" in core.clj line 66 are causing NPE. Removing them makes the tests to pass.

Test case :

(is (= '("clojure.core" "clojure.core.ArrayChunk" "clojure.core.ArrayManager" "clojure.core.IVecImpl" "clojure.core.Vec" "clojure.core.VecNode" "clojure.core.VecSeq" "clojure.core.protocols" "clojure.core.protocols.InternalReduce") (completions "clojure.co")))

$ lein test

lein test complete.core-test

lein test :only complete.core-test/completions-test

ERROR in (completions-test) (FutureTask.java:123)
expected: (= (quote ("clojure.core" "clojure.core.ArrayChunk" "clojure.core.ArrayManager" "clojure.core.IVecImpl" "clojure.core.Vec" "clojure.core.VecNode" "clojure.core.VecSeq" "clojure.core.protocols" "clojure.core.protocols.InternalReduce")) (completions "clojure.co"))
  actual: java.util.concurrent.ExecutionException: java.lang.NullPointerException
 at java.util.concurrent.FutureTask.report (FutureTask.java:123)
    java.util.concurrent.FutureTask.get (FutureTask.java:193)
    clojure.core$future_call$reify__5684.deref (core.clj:6054)
    clojure.core$deref.invoke (core.clj:2078)
    complete.core$eval384$fn__385.invoke (core.clj:112)
    clojure.lang.MultiFn.invoke (MultiFn.java:167)
    complete.core$completions.invoke (core.clj:128)
    complete.core$completions.invoke (core.clj:126)
    complete.core_test$fn__407$fn__420.invoke (core_test.clj:15)
    complete.core_test/fn (core_test.clj:14)
    clojure.test$test_var$fn__6484.invoke (test.clj:693)
    clojure.test$test_var.invoke (test.clj:693)
    clojure.test$test_all_vars$fn__6488$fn__6495.invoke (test.clj:709)
    clojure.test$default_fixture.invoke (test.clj:663)
    clojure.test$test_all_vars$fn__6488.invoke (test.clj:709)
    clojure.test$default_fixture.invoke (test.clj:663)
    clojure.test$test_all_vars.invoke (test.clj:705)
    clojure.test$test_ns.invoke (test.clj:728)
    user$eval77$fn__126.invoke (form-init265966808124094054.clj:1)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.AFn.applyTo (AFn.java:151)
    clojure.core$apply.invoke (core.clj:602)
    leiningen.core.injected$compose_hooks$fn__15.doInvoke (form-init265966808124094054.clj:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:600)
    leiningen.core.injected$run_hooks.invoke (form-init265966808124094054.clj:1)
    leiningen.core.injected$prepare_for_hooks$fn__20$fn__21.doInvoke (form-init265966808124094054.clj:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.lang.AFunction$1.doInvoke (AFunction.java:29)
    clojure.lang.RestFn.invoke (RestFn.java:408)
    clojure.core$map$fn__3811.invoke (core.clj:2432)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.Cons.next (Cons.java:39)
    clojure.lang.RT.boundedLength (RT.java:1607)
    clojure.lang.RestFn.applyTo (RestFn.java:130)
    clojure.core$apply.invoke (core.clj:602)
    clojure.test$run_tests.doInvoke (test.clj:743)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:600)
    user$eval77$fn__136$fn__167.invoke (form-init265966808124094054.clj:1)
    user$eval77$fn__136$fn__137.invoke (form-init265966808124094054.clj:1)
    user$eval77$fn__136.invoke (form-init265966808124094054.clj:1)
    user$eval77.invoke (form-init265966808124094054.clj:1)
    clojure.lang.Compiler.eval (Compiler.java:6465)
    clojure.lang.Compiler.eval (Compiler.java:6455)
    clojure.lang.Compiler.load (Compiler.java:6902)
    clojure.lang.Compiler.loadFile (Compiler.java:6863)
    clojure.main$load_script.invoke (main.clj:282)
    clojure.main$init_opt.invoke (main.clj:287)
    clojure.main$initialize.invoke (main.clj:315)
    clojure.main$null_opt.invoke (main.clj:348)
    clojure.main$main.doInvoke (main.clj:426)
    clojure.lang.RestFn.invoke (RestFn.java:421)
    clojure.lang.Var.invoke (Var.java:405)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.Var.applyTo (Var.java:518)
    clojure.main.main (main.java:37)
Caused by: java.lang.NullPointerException: null
 at complete.core$fn__307$iter__299__308$fn__309.invoke (core.clj:66)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.RT.seq (RT.java:466)
    clojure.core$seq.invoke (core.clj:133)
    complete.core$fn__334$iter__335__339$fn__340.invoke (core.clj:76)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.RT.seq (RT.java:466)
    clojure.core$seq.invoke (core.clj:133)
    clojure.core$dorun.invoke (core.clj:2723)
    clojure.core$doall.invoke (core.clj:2739)
    complete.core/fn (core.clj:76)
    clojure.core$binding_conveyor_fn$fn__3713.invoke (core.clj:1817)
    clojure.lang.AFn.call (AFn.java:18)
    java.util.concurrent.FutureTask.run (FutureTask.java:266)
    java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1158)
    java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:632)
    java.lang.Thread.run (Thread.java:804)

lein test :only complete.core-test/completions-test

ERROR in (completions-test) (FutureTask.java:123)
expected: (= (quote ("complete.core" "complete.core-test")) (completions "complete.core"))
  actual: java.util.concurrent.ExecutionException: java.lang.NullPointerException
 at java.util.concurrent.FutureTask.report (FutureTask.java:123)
    java.util.concurrent.FutureTask.get (FutureTask.java:193)
    clojure.core$future_call$reify__5684.deref (core.clj:6054)
    clojure.core$deref.invoke (core.clj:2078)
    complete.core$eval384$fn__385.invoke (core.clj:112)
    clojure.lang.MultiFn.invoke (MultiFn.java:167)
    complete.core$completions.invoke (core.clj:128)
    complete.core$completions.invoke (core.clj:126)
    complete.core_test$fn__407$fn__424.invoke (core_test.clj:18)
    complete.core_test/fn (core_test.clj:17)
    clojure.test$test_var$fn__6484.invoke (test.clj:693)
    clojure.test$test_var.invoke (test.clj:693)
    clojure.test$test_all_vars$fn__6488$fn__6495.invoke (test.clj:709)
    clojure.test$default_fixture.invoke (test.clj:663)
    clojure.test$test_all_vars$fn__6488.invoke (test.clj:709)
    clojure.test$default_fixture.invoke (test.clj:663)
    clojure.test$test_all_vars.invoke (test.clj:705)
    clojure.test$test_ns.invoke (test.clj:728)
    user$eval77$fn__126.invoke (form-init265966808124094054.clj:1)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.AFn.applyTo (AFn.java:151)
    clojure.core$apply.invoke (core.clj:602)
    leiningen.core.injected$compose_hooks$fn__15.doInvoke (form-init265966808124094054.clj:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:600)
    leiningen.core.injected$run_hooks.invoke (form-init265966808124094054.clj:1)
    leiningen.core.injected$prepare_for_hooks$fn__20$fn__21.doInvoke (form-init265966808124094054.clj:1)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.lang.AFunction$1.doInvoke (AFunction.java:29)
    clojure.lang.RestFn.invoke (RestFn.java:408)
    clojure.core$map$fn__3811.invoke (core.clj:2432)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.Cons.next (Cons.java:39)
    clojure.lang.RT.boundedLength (RT.java:1607)
    clojure.lang.RestFn.applyTo (RestFn.java:130)
    clojure.core$apply.invoke (core.clj:602)
    clojure.test$run_tests.doInvoke (test.clj:743)
    clojure.lang.RestFn.applyTo (RestFn.java:137)
    clojure.core$apply.invoke (core.clj:600)
    user$eval77$fn__136$fn__167.invoke (form-init265966808124094054.clj:1)
    user$eval77$fn__136$fn__137.invoke (form-init265966808124094054.clj:1)
    user$eval77$fn__136.invoke (form-init265966808124094054.clj:1)
    user$eval77.invoke (form-init265966808124094054.clj:1)
    clojure.lang.Compiler.eval (Compiler.java:6465)
    clojure.lang.Compiler.eval (Compiler.java:6455)
    clojure.lang.Compiler.load (Compiler.java:6902)
    clojure.lang.Compiler.loadFile (Compiler.java:6863)
    clojure.main$load_script.invoke (main.clj:282)
    clojure.main$init_opt.invoke (main.clj:287)
    clojure.main$initialize.invoke (main.clj:315)
    clojure.main$null_opt.invoke (main.clj:348)
    clojure.main$main.doInvoke (main.clj:426)
    clojure.lang.RestFn.invoke (RestFn.java:421)
    clojure.lang.Var.invoke (Var.java:405)
    clojure.lang.AFn.applyToHelper (AFn.java:163)
    clojure.lang.Var.applyTo (Var.java:518)
    clojure.main.main (main.java:37)
Caused by: java.lang.NullPointerException: null
 at complete.core$fn__307$iter__299__308$fn__309.invoke (core.clj:66)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.RT.seq (RT.java:466)
    clojure.core$seq.invoke (core.clj:133)
    complete.core$fn__334$iter__335__339$fn__340.invoke (core.clj:76)
    clojure.lang.LazySeq.sval (LazySeq.java:42)
    clojure.lang.LazySeq.seq (LazySeq.java:60)
    clojure.lang.RT.seq (RT.java:466)
    clojure.core$seq.invoke (core.clj:133)
    clojure.core$dorun.invoke (core.clj:2723)
    clojure.core$doall.invoke (core.clj:2739)
    complete.core/fn (core.clj:76)
    clojure.core$binding_conveyor_fn$fn__3713.invoke (core.clj:1817)
    clojure.lang.AFn.call (AFn.java:18)
    java.util.concurrent.FutureTask.run (FutureTask.java:266)
    java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1158)
    java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:632)
    java.lang.Thread.run (Thread.java:804)

$ clj
Clojure 1.9.0
user=> (import [java.io File])
java.io.File
user=> (for [prop ["sun.boot.class.path" "java.ext.dirs" "java.class.path"]
      path (.split (System/getProperty prop) File/pathSeparator)] path)
NullPointerException   user/eval171/iter--165--172/fn--173 (NO_SOURCE_FILE:5)
user=> (.split (System/getProperty "sun.boot.class.path") File/pathSeparator)
NullPointerException   user/eval192 (NO_SOURCE_FILE:7)
user=> (.split (System/getProperty "java.ext.dirs") File/pathSeparator)
NullPointerException   user/eval194 (NO_SOURCE_FILE:8)
user=> (.split (System/getProperty "java.class.path") File/pathSeparator)
#object["[Ljava.lang.String;" 0x78de58ea "[Ljava.lang.String;@78de58ea"]

[tirkarthi]

http://www.oracle.com/technetwork/java/javase/9-relnote-issues-3704069.html

The system property sun.boot.class.path has been removed.

#23 reports the other path

[tirkarthi]

PR #25 for this issue