fix: catch exceptions from SourceMapConsumer

[afischer-sfly]

The symptom of this issue is that the test runner will die with the following error:

Fatal error: Line must be greater than or equal to 1, got 0

The way the error happened:

1. One of my specs was failing when calling getComputedStyle(). In Firefox this resulted in an error message with some weird formatting: "TypeError: Argument 1 of Window.getComputedStyle does not implement interface Element. in http://172.20.132.80:8080/base/app/SilverApp/services/DragAvatarProducer.js?dc125e476a15c0e2f62b00901b3d0c1b6c407af8 (line 85)". The problem with that string is the line number is formatted "(line 85)" when it should be like ":85:7". This might be a bug against Firefox.
2. Karma's source-map support tried to parse the line & column, but couldn't because the formatting was weird. (see: https://github.com/karma-runner/karma/blob/master/lib/reporter.js#L36 )
3. Karma uses defaults of 0 for the line & column numbers. (see: https://github.com/karma-runner/karma/blob/master/lib/reporter.js#L45 )
4. The source-map library throws an exception if line or column is 0. (see: https://github.com/mozilla/source-map/blob/master/lib/source-map/source-map-consumer.js#L277 )

This pull request wraps SourceMapConsumer.originalPositionFor in a try-catch block.

[L1fescape]

I ran into a similar problem. Karma was just dying with

Fatal error: Line must be greater than or equal to 1, got 0

and I couldn't figure out why. After modifying lib/reporter.js with the code in this pull request I was able to get karma to tell me it was failing on a Maximum call stack size exceeded error from my code, which I was able to fix. After that I reset lib/reporter.js back to what it originally was and everything worked fine.

Side note: I'm using browserify, and I think with Maximum call stack size exceeded a line number isn't returned with the exception.

[jeeyoungk]

i'm running into the similar error - is there any way this is going to be merged soon?

[maksimr]

I think we can output to warn log message about failing SourceMapConsumer

[maksimr]

Some other way to solve this problem:

1. Set default value '1' for line number
2. Change regexp which extract line number and column so it works only with line

[paldepind]

👍

[maksimr]

\cc @afischer-sfly @akenn @jeeyoungk @paldepind

Guys are you use karma-jasmine?

[vojtajina]

Thanks @afischer-sfly I agree this needs to be fixed.
I think we should correct the regular expression to parse Firefox error stacks, instead of ignoring these errors.

[mtscout6]

Using this change I see the following:

➜  one-exchange git:(team-4) ✗ karma start
INFO [karma]: Karma v0.12.31 server started at http://localhost:9876/
INFO [launcher]: Starting browser Chrome
INFO [launcher]: Starting browser Firefox
INFO [launcher]: Starting browser PhantomJS
INFO [Chrome 40.0.2214 (Mac OS X 10.10.2)]: Connected on socket KvQfC30d23P_S4-w9Pwz with id 6138033
INFO [PhantomJS 1.9.7 (Mac OS X)]: Connected on socket bOGR9WbBI4Jm2kwc9Pw0 with id 9003323
INFO [Firefox 34.0.0 (Mac OS X 10.10)]: Connected on socket Ub3snpehdDscQ1HY9Pw1 with id 74944863
PhantomJS 1.9.7 (Mac OS X) Directive: addToCart toggles the text FAILED
        ReferenceError: Can't find variable: test
            at /mnt/Resources/dev/one-exchange/src/ExtendHealth.OneExchange/content/scripts/specs/test-main.js:218:0 <- webpack:///src/ExtendHealth.OneExchange/content/scripts/specs/add-to-cart-directive-spec.js:58:0
Firefox 34.0.0 (Mac OS X 10.10) Directive: addToCart toggles the text FAILED
        ReferenceError: test is not defined in /mnt/Resources/dev/one-exchange/src/ExtendHealth.OneExchange/content/scripts/specs/test-main.js (line 218)
        __WEBPACK_AMD_DEFINE_RESULT__</</<@/mnt/Resources/dev/one-exchange/src/ExtendHealth.OneExchange/content/scripts/specs/test-main.js:218:10 <- webpack:///src/ExtendHealth.OneExchange/content/scripts/specs/add-to-cart-directive-spec.js:58:0

Chrome 40.0.2214 (Mac OS X 10.10.2) Directive: addToCart toggles the text FAILED
        ReferenceError: test is not defined
            at null.<anonymous> (/mnt/Resources/dev/one-exchange/src/ExtendHealth.OneExchange/content/scripts/specs/test-main.js:218:10 <- webpack:///src/ExtendHealth.OneExchange/content/scripts/specs/add-to-cart-directive-spec.js:58:0)
PhantomJS 1.9.7 (Mac OS X): Executed 1 of 2002 (1 FAILED) (skipped 2001) ERROR (0.711 secs / 0.023 secs)
Firefox 34.0.0 (Mac OS X 10.10): Executed 1 of 2002 (1 FAILED) (skipped 2001) ERROR (2.245 secs / 0.043 secs)
Chrome 40.0.2214 (Mac OS X 10.10.2): Executed 1 of 2002 (1 FAILED) (skipped 2001) ERROR (0.66 secs / 0.059 secs)

The issue with Firefox here is that it looks like the first line contains a line number, but the stack trace hasn't actually started yet. The next line is the actual stack trace and the source map works as expected. In this case I think just logging a warning that there was an error in the SourceMapConsumer would suffice, and you shouldn't need to change the existing regex at all. Or maybe forego attempting source map line number changes on the first line of an error, but I don't know how well that will play with all the other browsers that I'm not using.

[phun-ky]

When can we get this PR in? +1

[maksimr]

@afischer-sfly can you rebase on master and logging error

Thanks

[afischer-sfly]

no problem, just pushed a revised change that includes logging. Happy to make any other changes too.

\cc @afischer-sfly @akenn @jeeyoungk @paldepind

Guys are you use karma-jasmine?

Yup we use karma-jasmine

[maksimr]

@afischer-sfly Thanks!

Left to correct jshint errors

[jmcmichael]

For what it's worth, I'm using karma, mocha, chai, sinon and got the 'TypeError: Line must be greater or equal to 1, got 0' from source-map when setting up sinon-as-promised. Applying this PR fixed it.

[maksimr]

LGTM

[dazz]

👍 When can we get this PR in?

[maksimr]

@dazz
When somebody else from karma team make review this issue

Thanks

[mtscout6]

/cc @karma-runner/owners Can we get a second sign off on this?

[jerryorr]

I use karma + jasmine and got this error when running against Firefox (not Chrome, interestingly). This patch fixed it.

[Sjors]

I ran into the same error with Phantomjs2. I then added the commit from this pull request to the current master in my own fork, ran "grunt build" and the error was replaced by a warning. That and lots of other error messages, but hopefully those are specific to my project.

[BrentWheeldon]

Can this get merged in, please?

[zzo]

Thanks @maksimr! Still working on getting the release process sorted out.

[maksimr]

@zoo no problems!

This PR fix only symptom, source of the problem I describe here. Under the task #1274 we can make more robust solution, about which said @vojtajina

I think we should correct the regular expression to parse Firefox error stacks, instead of ignoring these errors.

[dtabuenc]

I don't like just catching the error, but it seems to me it shouldn't even try to get original location from sourcemap if the regular expression did not match a line number.