Observatory when compiled to JavaScript gets DecodeException on well formed JSON

[johnmccutchan]

Observatory when compiled to JavaScript gets DecodeException on well formed JSON.

DecodeException: Error: number is not a function

[johnmccutchan]

Marked this as blocking #18358.

[johnmccutchan]

Attached is json-parse.js which is a single call to JSON.parse with the JSON string that failed to decode in dart2js.

Note that d8 has no problem parsing it.

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Attachment:
json-parse.js (898.53 KB)

[johnmccutchan]

Reproduction steps:

Using a bleeding_edge build:

1. git clone https://github.com/dart-lang/dart-box2d.git
2. dart --enable-vm-service --pause-isolates-on-exit example/benchmarks/benchmark_runner.dart
3. Connect to localhost:8181 and click on the profile link.
4. Hit on-page-refresh button (upper right corner) on the profile page until you get the decode error.

[johnmccutchan]

Couple of other notes:

1. I've never seen this issue when running the Dart version of Observatory.
2. The JSON is valid (I've tested with multiple JSON lint tools) and d8 will parse it.

[johnmccutchan]

Attached is a trivial reproduction program written in Dart that when compiled to JavaScript fails to execute. The call stack from dart2js compiled program:

$ dart2js -o test.js json-parse.dart
$ d8 test.js

/usr/local/google/home/johnmccutchan/test.js:1205: TypeError: number is not a function
        map.$indexSet(0, key, t1.call$2(key, this.call$1(e[key])));
            ^
TypeError: number is not a function
    at _convertJsonToDart_walk.call$1 (/usr/local/google/home/johnmccutchan/test.js:1205:13)
    at _convertJsonToDart_walk.call$1 (/usr/local/google/home/johnmccutchan/test.js:1205:34)
    at _convertJsonToDart_walk.call$1 (/usr/local/google/home/johnmccutchan/test.js:1205:34)
    at _convertJsonToDart_walk.call$1 (/usr/local/google/home/johnmccutchan/test.js:1198:24)
    at _convertJsonToDart_walk.call$1 (/usr/local/google/home/johnmccutchan/test.js:1205:51)
    at dart._convertJsonToDart (/usr/local/google/home/johnmccutchan/test.js:1165:70)
    at dart._parseJson (/usr/local/google/home/johnmccutchan/test.js:1181:14)
    at JsonCodec.decode$2$reviver (/usr/local/google/home/johnmccutchan/test.js:1222:16)
    at JsonCodec.decode$1 (/usr/local/google/home/johnmccutchan/test.js:1225:19)
    at dart.main (/usr/local/google/home/johnmccutchan/test.js:1398:42)

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Attachment:
json-parse.dart (898.58 KB)

[rakudrama]

This looks like a V8 bug.
The program from #­5 is attached

$ third_party/d8/linux/d8 out.js
Crashes like above

$ third_party/firefox_jsshell/linux/js out.js
Runs fine.

V8 version 3.25.28.11

[rakudrama]

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Attachment:
out.js (1.08 MB)

[johnmccutchan]

Related V8 bug: https://code.google.com/p/v8/issues/detail?id=3282

[anders-sandholm]

Removed Library-Json label.
Added Library-Convert label.

[floitschG]

Issue #18436 has been merged into this issue.

[floitschG]

Issue #18436 has been merged into this issue.

[lrhn]

Issue #18616 has been merged into this issue.

[alan-knight]

Issue #18689 has been merged into this issue.

[DartBot]

This comment was originally written by magus...@gmail.com

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Hi guys, I noticed on Issue #18436 that floitsch commented this is already fixed in bleeding edge (that was around the end of April). Do you know what dev build it is fixed in, or better yet what stable release it should come in?

[johnmccutchan]

Hi,

This was actually a bug in V8 and was fixed in Chrome 35.

John

[DartBot]

This comment was originally written by magus...@gmail.com

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Oh really...interesting. Because I think I have a potentially similar error. I guess I'll have to wait till I'm in work again tomorrow to try an replicate it (shouldn't be hard hopefully) but essentially AFAICT it's a similar error with "number is not a function" message...

I'd have to check to be absolutely sure, but I don't know of any reason why it wouldn't have been Chrome 35 that I was using.

[DartBot]

This comment was originally written by magusofic...@gmail.com

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Actually sorry...I didn't realise Chrome 35 only went stable so recently. May I was using Chrome 34 after all...I'm a bit confused now as to when I first encountered this error :/ But at least now it seems like it's not occurring any more.

[kasperl]

Has this issue gone away with Chrome 35?

[kasperl]

I guess we don't expect to take any action on this on the Dart side. Marking as 'not planned'.

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Added NotPlanned label.