Integrated tests with Lerna (does not include Block for now)

[evertonfraga]

Down the road of the monorepo transition, this PR introduces integrated module testing, powered by Lerna bootstrap command, with some additional configuration. This enables us to detect possible disruption of downstream libraries before releasing.

The monorepo codebase had Block in a non-production state (3.0.0), that wasn't integrated to the other packages at all, making this very transition a bit cumbersome.

Note to reviewers: I advise review looking at one commit at a time. It contains:

1. Reverts Block code to 2.2.2. This is an inflated commit (12d503d)
2. Removes NodeJS 8.x from tests (soon we'll include node 14) (e8e3201)
3. Removes specific code and scripts for running tests with ts-node with linked packages, which will come at a later stage. (74890a2) and (8d5f3c0)
4. Configures test coverage using the same standard as other ethereumjs-VM packages(ca04215)
5. Puts lerna commands in place (75b0479).

This commit (75b0479) also disables node_modules cache on GitHub Actions test suite. They consider shallow paths (./node_modules), and generic caching keys, which was 100% correct before the monorepo transition. Related: #730

This PR replaces #725 and should be merged to master instead.

[codecov]

Codecov Report

Merging #734 into master will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #734      +/-   ##
==========================================
- Coverage   91.72%   91.71%   -0.01%     
==========================================
  Files          47       46       -1     
  Lines        3008     3005       -3     
  Branches      468      468              
==========================================
- Hits         2759     2756       -3     
  Misses        151      151              
  Partials       98       98              

Flag	Coverage Δ
#account	94.11% <ø> (ø)
#block	88.36% <ø> (ø)
#blockchain	89.15% <ø> (ø)
#common	94.26% <ø> (-0.11%)	⬇️
#tx	94.11% <ø> (ø)
#vm	92.53% <ø> (ø)

Impacted Files	Coverage Δ
packages/common/src/genesisStates/index.ts	100.00% <0.00%> (ø)
packages/common/src/hardforks/index.ts

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[holgerd77]

This "revert Block code to 2.2.2" thing makes me a bit nervous since it is a pretty heavy and invasive step, is this really necessary to achieve what you want? How will you achieve to get these changes in again with a retained authorship and stuff like that? 🤔

[evertonfraga]

You were right @holgerd77, and in the end I just wanted to verify that all the production packages worked well in this new scenario, no need for it to reach master. It did worked nicely, then I moved back to Block v3 source code.

After a surgical rebase, I removed the Revert Block to 2.2.2, along with some other Block-specific commits. I also edited the test: enabling Lerna for integrated tests, excluding the Lerna changes to Block, amending the commit message to test: enabling Lerna for integrated tests, all packages but Block.

These changes guarantees all packages (but Block) work well in conjunction, so we can finally tackle the Block v3 migration with more confidence.

[evertonfraga]

For this PR, Block won't use Lerna for linking packages. So in both CIs, we need to explicitly keep npm install for Block package.

[evertonfraga]

This is important: it tells Lerna to ignore ethereumjs-block from lerna bootstrap commands. It will still be used on lerna run and lerna exec for the time being.

[ryanio]

Great, would love to add this to our global prettier config in the future 👍

[ryanio]

Looks great, thanks for all your hard work on this!

[holgerd77]

👍