Use Lodash's mergeWith and warn when losing reactivity

[kinow]

These changes close #589 (and removes an unnecessary console.log from tests)

Requirements check-list

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Appropriate tests are included (unit and/or functional).
• No change log entry required (why? e.g. invisible to users).
• No documentation update required.

[codecov-io]

Codecov Report

Merging #591 (0623007) into master (a5c7750) will decrease coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #591      +/-   ##
==========================================
- Coverage   81.66%   81.61%   -0.05%     
==========================================
  Files          66       66              
  Lines        1320     1322       +2     
  Branches       81       81              
==========================================
+ Hits         1078     1079       +1     
- Misses        223      224       +1     
  Partials       19       19              

Flag	Coverage Δ
e2e	48.56% <0.00%> (-0.15%)	⬇️
unittests	79.92% <100.00%> (+0.03%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/components/cylc/tree/cylc-tree.js	99.31% <100.00%> (-0.69%)	⬇️

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[kinow]

With this change, and without #586 , when we hold or release a workflow we get

[kinow]

I think this should be ready for review. Just waiting for CI to complete, and codecov to confirm the code is covered.

@hjoliver after this change, we should see a warning, until #586 is merged. After #586 is merged, we shouldn't — in theory — see any warning again. But if we see the warning in the console, we won't have to spend time investigating reactivity issues in deltas (no fun!) 👍

[kinow]

Funny. The macos build failed. Re-ran all jobs, then now ubuntu+firefox failed. 😕

Working for me locally. Third time's the charm. Let's kick it once again.

[oliver-sanders]

Perhaps we have a flaky test, which test was failing?

[kinow]

Perhaps we have a flaky test, which test was failing?

The build workflow error was due to a no-console that I forgot. The macos build (or job, sorry I keep using both with GH actions) keeps failing when it tries to execute Cypress, before running the tests.

Today: https://github.com/cylc/cylc-ui/actions/runs/555846220

 info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
info There appears to be trouble with your network connection. Retrying...
error An unexpected error occurred: "https://registry.yarnpkg.com/rxjs/-/rxjs-6.6.2.tgz: ESOCKETTIMEDOUT".
info If you think this is a bug, please open a bug report with the information provided in "/Users/runner/work/cylc-ui/cylc-ui/yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.
info There appears to be trouble with your network connection. Retrying...
Error: The process '/Users/runner/.yarn/bin/yarn' failed with exit code 1

From 2 days ago, this branch too: https://github.com/cylc/cylc-ui/actions/runs/552663688

Done in 266.80s.
/usr/local/bin/npx cypress cache list
┌─────────┬──────────────┐
│ version │ last used    │
├─────────┼──────────────┤
│ 6.1.0   │ 2 months ago │
└─────────┴──────────────┘
/usr/local/bin/npx cypress verify

25l[21:33:50]  Verifying Cypress can run /Users/runner/.cache/Cypress/6.1.0/Cypress.app [started]
[21:34:20]  Verifying Cypress can run /Users/runner/.cache/Cypress/6.1.0/Cypress.app [failed]
25hCypress verification timed out.

This command failed with the following output:

/Users/runner/.cache/Cypress/6.1.0/Cypress.app/Contents/MacOS/Cypress --no-sandbox --smoke-test --ping=107

----------

Command timed out after 30000 milliseconds: /Users/runner/.cache/Cypress/6.1.0/Cypress.app/Contents/MacOS/Cypress --no-sandbox --smoke-test --ping=107
Timed out

----------

Platform: darwin (19.6.0)
Cypress Version: 6.1.0
25h::debug::The process '/usr/local/bin/npx' failed with exit code 1
Error: The process '/usr/local/bin/npx' failed with exit code 1

[oliver-sanders]

Ok, have an idea what might be causing that, #592

[oliver-sanders]

Tried upgrading to Yarn2, however, got a load of errors, will need to go through the migration guide properly. Perhaps worth waiting for Yarn2 to stabilise first, dumping in an issue for now.

#593

[oliver-sanders]

Test failure nothing to do with this branch.

[kinow]

I think I found an alternative to this PR, that would add reactivity to an object, instead of just warning. Testing will take a little bit (browser + IDE)

[kinow]

I'm pushing an improved solution to #530 as that branches also has issues with reactivity after deltas are merged. Once that one is merged, will leave this one open a little longer while I look at other PR's, to make sure this issue is really gone.

[kinow]

So far looks like the new solution worked on #530 . If that PR is closed, then this one can be closed as superseded (it has the same code, with a small modification in the merge customizer using Vue.set instead of just warning).

[kinow]

Confirmed it's closed by #530