Unit tests for all components

[vpulim]

This PR adds unit tests for all components.

• logging
• blockchain
• handler
• net/peer
• net/peerpool
• net/protocol
• net/server
• rpc
• service
• sync
• util
• node

[coveralls]

Coverage decreased (-3.2%) to 92.703% when pulling 231c166 on tests into a45c129 on master.

[holgerd77]

Whew, list completion makes some good progress. 👍 Out of interest: did you find (significant) bugs along the way? Or is everything just working as intended?

[vpulim]

@holgerd77 Just a few bugs... nothing significant. Here are some examples:

1. Block incorrectly wrapped in a Promise: https://github.com/ethereumjs/ethereumjs-client/pull/70/files#diff-939c5cdcb48ce94b997a3d8b68a04b61L90
2. Another incorrect wrapping in a Promise: https://github.com/ethereumjs/ethereumjs-client/pull/70/files#diff-ea1cea58e6f009f5587836522e31cb9fL58
3. Wrong default value: https://github.com/ethereumjs/ethereumjs-client/pull/70/files#diff-ef6d31d2252057eea76e75a9a56715eeL16
4. Missing reject value: https://github.com/ethereumjs/ethereumjs-client/pull/70/files#diff-b131dd2a34954a13576e8d0bf8267c99L204

I think TypeScript would have helped catch most of these cases

[holgerd77]

Just out of interest, no need to change here on the last stages: why are you doing this in such a monster 🐲 PR and not adding test types PR by PR? Does this have advantages regarding working out utility functions or something?

[vpulim]

No real advantages. Just wanted to avoid polluting the commit history. Also, I underestimated the amount of work 😂

In hindsight, if I had known how much work it would be, I would have created a tracking issue and done this PR by PR so that it would have been easier for others to contribute tests.

[holgerd77]

Hehe. 😛

[holgerd77]

Whew. A whopping > 2.000 lines of code added. Not in all cases of software dev a sign for quality, but in this case really impressive! 👍

[vpulim]

😅Thanks @holgerd77. Not sure if it was worth it, but I did catch a few bugs and hopefully will identify any future bugs/typos. Now, on to integration tests! These should be more useful I think.

[holgerd77]

Think so too, this gives a very solid foundation and will likely pay off in the future! 😄