add travis-ci, run tests with phantomjs

[ericblade]

needs some additional work and discussion before merging.

[ericblade]

So, this gets the test process working non-interactively, but there are 3 errors existing in the current test cases. I haven't yet had time to see if the tests themselves are broken, or if there's something up with the library.

First error:

'image-001.jpg'
PhantomJS 2.1.1 (Linux 0.0.0): Executed 1 of 11 SUCCESS (0 secs / 0.944 secs)
PhantomJS 2.1.1 (Linux 0.0.0) decodeSingle EAN-extended should decode base/test/fixtures/ean_extended/ correctly FAILED
	TypeError: undefined is not an object (evaluating 'result.codeResult.code') (test/test-main-integration.js:14676)
PhantomJS 2.1.1 (Linux 0.0.0): Executed 2 of 11 (1 FAILED) (0 secs / NaN secs)
'image-001.jpg'

Second error (looks to be same as first error, different test though)

'image-007.jpg'
PhantomJS 2.1.1 (Linux 0.0.0): Executed 3 of 11 (1 FAILED) (0 secs / NaN secs)
PhantomJS 2.1.1 (Linux 0.0.0) decodeSingle Code39 should decode base/test/fixtures/code_39/ correctly FAILED
	TypeError: undefined is not an object (evaluating 'result.codeResult.code') (test/test-main-integration.js:14676)
PhantomJS 2.1.1 (Linux 0.0.0): Executed 4 of 11 (2 FAILED) (0 secs / NaN secs)
'image-001.jpg'

Third error looks like a decode error

'image-005.jpg'
PhantomJS 2.1.1 (Linux 0.0.0): Executed 4 of 11 (2 FAILED) (0 secs / NaN secs)
PhantomJS 2.1.1 (Linux 0.0.0) decodeSingle EAN-8 should decode base/test/fixtures/ean_8/ correctly FAILED
	AssertionError: expected '74070749' to equal '90162602' (node_modules/chai/chai.js:210)
PhantomJS 2.1.1 (Linux 0.0.0): Executed 5 of 11 (3 FAILED) (0 secs / NaN secs)
'image-001.jpg'

[ericblade]

ok, so, for ean_extended/image-001.jpg and code_39/image-007.jpg the callback is being called without a codeResult. For ean_8/image-005.jpg, it's returning the wrong code.

[ericblade]

Sometimes, the 3rd error (ean_8/image-005.jpg) doesn't come up, but sometimes a different third one does:

LOG: 'image-001.jpg'
PhantomJS 2.1.1 (Windows 8.0.0) decodeSingle UPC-E should decode base/test/fixtures/upc_e/ correctly FAILED
        AssertionError: expected undefined to be an object (http:https://localhost:9877node_modules/chai/chai.js:210)

So, it seems we have some non-deterministic results coming from ean_8 and upc_e .. and some total failures from ean_2_reader and code_39.

[ericblade]

Consistently, on the travis machine that was doing testing, the tests that I commented out here failed 74d8673

... but they did not fail for me on my local machine. It seems to me that there's definitely some strange things afoot in some of the readers, possibly?

[ericblade]

I don't want to merge this until there's some input from others -- not just "looks good", but in regards to the actual functionality -- I couldn't get the tests to run in Chrome at all, I don't know if I was failing at some configuration step or missing some step, or what.

I don't know if there's any disadvantages to running in PhantomJS versus Chrome, so long as Phantom has the support for what is needed (which it seems to, after plugging in the Promises polyfill for it) . . I would think that for now, it would be good to go with it.

I'm not sure if there's an easy way to enable the "watch" mode for testing -- I disabled it here so that the Travis builds would complete, instead of hang watching for file updates .. i'd definitely like to have file watcher on for tests, though, that's super convenient to do quick changes in development.

Basically, I'm sure that this is a change that is in the right direction, for the time being, but we may have to go in a different direction with some of these changes, or add more to these changes, such as not eliminating test watching. :-)