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NullPointerException when adding prototypical properties on a record in an extern

See original GitHub issue

Summary

In this commit to Polymer, I tried adding some instance properties of a mixin class onto the corresponding record and hit a 100% repro NullPointerException when compiling.

Setup

This requires Node and NPM

Check out https://github.com/Polymer/polymer/tree/compiler-error
Run npm run reproduce

Output will look something like this:

[16:59:03] gulp-google-closure-compiler: java.lang.NullPointerException
	at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:770)
	at com.google.javascript.jscomp.GlobalTypeInfo.checkSuperProperty(GlobalTypeInfo.java:784)
	at com.google.javascript.jscomp.GlobalTypeInfo.checkAndFreezeNominalType(GlobalTypeInfo.java:647)
	at com.google.javascript.jscomp.GlobalTypeInfo.process(GlobalTypeInfo.java:484)
	at com.google.javascript.jscomp.PhaseOptimizer$NamedPass.process(PhaseOptimizer.java:305)
	at com.google.javascript.jscomp.PhaseOptimizer.process(PhaseOptimizer.java:231)
	at com.google.javascript.jscomp.Compiler.check(Compiler.java:1110)
	at com.google.javascript.jscomp.Compiler.performChecksAndTranspilation(Compiler.java:910)
	at com.google.javascript.jscomp.Compiler.access$000(Compiler.java:101)
	at com.google.javascript.jscomp.Compiler$3.call(Compiler.java:844)
	at com.google.javascript.jscomp.Compiler$3.call(Compiler.java:841)
	at com.google.javascript.jscomp.CompilerExecutor$2.call(CompilerExecutor.java:93)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:748)

Issue Analytics

State:
Created 6 years ago
Comments:12 (9 by maintainers)

Top GitHub Comments

1reaction

dimvarcommented, Jul 12, 2017

I sent a fix for this internally for review. Hopefully it will be pushed externally tomorrow.

0reactions

dimvarcommented, Jul 11, 2017

I reproduced this and I’m in the process of debugging. I haven’t gotten to a small repro yet.

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