Drop ethereumjs-testing dep and fix bug in branch value update

[s1na]

This PR upgrades drops ethereumjs-testing dependency, adds the test fixture files directly to the repository and fixes #54 which caused a new test case to fail.

[holgerd77]

Will do an ethereumjs-testing update in a minute 😄 together with a v1.2.6 release. If you want you can directly upgrade to this. Shouldn't have any effect though since trie tests very likely haven't been touched, so would be only for the "optics". 😛

[coveralls]

Coverage increased (+0.1%) to 94.444% when pulling 8d658c4 on chore/upgrade-ethereumjs-testing into 5b227a1 on master.

[s1na]

@holgerd77 Sure, we might as well upgrade to the latest version :)

Browsers tests are now failing. It seems ethereumjs-testing depends on asyncawait which depends on node-fibers which doesn't work in browsers! Searching more to see if there's a workaround.

[holgerd77]

Just did the v1.2.6 release.

[s1na]

@holgerd77 Even without the asyncawait issue karma isn't able to find the json test files from ethereumjs-testing. Do you have any ideas? Do other projects run ethereumjs-testing tests also in browser?

[holgerd77]

Hmm, not sure. @danjm is also working on a tests update ethereumjs/ethereumjs-tx#131 on the tx library and this library also has a browser test configuration and script. However the test run is deactivated in .travis.yml (which also shouldn't be the case, don't know the reasoning ad hoc).

Maybe the PR from Dan helps nevertheless, eventually you can check it out and see if the browser tests pass manually? Otherwise you can figure out together?

[holgerd77]

One other thing for consideration: these trie tests here are also pretty static, there was just one test case added in the last four years or so. Maybe we should also follow the path here to just remove this dependency all together like being done in ethereumjs/ethereumjs-block#61 for the block library (together with some copying and wrapping - see block PR-related issue - on the test files).

The tests dependency is a super-heavy several hundred MBs dependency which takes ages on installation, think this would very much make sense here too, think trie tests are just some KB compared.

[s1na]

@holgerd77 Took you on your offer 😄 Added the json test files directly to the repository and dropped ethereumjs-testing dependency. Tests are passing now.

[holgerd77]

Ah, but could you add the wrapping of the file structures with some meta fields for file information as well, see ethereumjs/ethereumjs-block#55 for reference.

[s1na]

Ah, I had missed that. Added the metadata.

[holgerd77]

Super-cool, great, thanks! 😄