Fix/jest esm babel

[patrickleet]

No description provided.

[benmccann]

Hmm. I don't know why Jest is always trying to load the .cjs version. It also looks like it's hardcoded to use transformSource and never uses transformSourceAsync. I think I'd probably report this as a bug to Jest and see if there's something that can be fixed there

https://github.com/facebook/jest/blob/bc50e7f360ab1845abbaa0b3ad788caead0d3174/packages/jest-reporters/src/generateEmptyCoverage.ts#L72

[patrickleet]

I think the require error is from jest.mock jestjs/jest#10025

[benmccann]

The thing about CJS / processAsync is coming from the coverage stuff. If you remove the coverage config from jest.json then those errors disappear. We should file a bug with Jest about that

Even with the coverage stuff removed the tests still fail though since the SvelteKit stuff hasn't been mocked due to lack of mocking support in ESM

[benmccann]

Hmm. I created a new project using coverage and svelte-jester 2.0 and everything's passing (https://github.com/benmccann/svelte-jest-add-example). I'm not sure what's different to be causing the failure here

[patrickleet]

Yea I played around with it more and got past that error but still unable to get mocks working correctly for anything beyond a basic example. which seems more like a jest/esm issue.

[benmccann]

Yeah, we'd need Jest to fix that. Maybe you could try this workaround in the meantime? jestjs/jest#10025 (comment)

[patrickleet]

@benmccann

I got a version of this working - will share pending some clean up, but used strategy from sveltejs/kit#1485 (comment)

collectCoverageFrom is what's causing those coverage errors - without it, there are not errors, however, it doesn't know which files to collect coverage from which throws it off a lot.

[codecov]

Codecov Report

Merging #30 (38dae5d) into master (715e4e3) will decrease coverage by 1.67%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #30      +/-   ##
==========================================
- Coverage   88.08%   86.40%   -1.68%     
==========================================
  Files          10       10              
  Lines         235      206      -29     
  Branches       17       17              
==========================================
- Hits          207      178      -29     
  Misses         28       28              

Impacted Files	Coverage Δ
src/routes/oto.svelte	66.66% <0.00%> (-7.25%)	⬇️
src/routes/upsell.svelte	66.66% <0.00%> (-7.25%)	⬇️
src/routes/downsell.svelte	66.66% <0.00%> (-7.25%)	⬇️
src/routes/index.svelte	81.25% <0.00%> (-4.47%)	⬇️
src/routes/checkout.svelte	83.33% <0.00%> (-3.63%)	⬇️
src/routes/thank-you.svelte	100.00% <0.00%> (ø)

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[patrickleet]

@benmccann pushed

I guess the combination of collectCoverageFrom and actual importing and testing things is enough for the coverage errors to go away - I now only see it for __layout, the only file I'm not explicitly testing

Running coverage on untested files...Failed to collect coverage from /Users/patrickleet/dev/cloudnativeentrepreneur/funnel/src/routes/__layout.svelte
ERROR: Jest: synchronous transformer /Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/svelte-jester/dist/transformer.cjs must export a "process" function.
STACK: Error: Jest: synchronous transformer /Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/svelte-jester/dist/transformer.cjs must export a "process" function.
    at invariant (/Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/@jest/transform/build/ScriptTransformer.js:1092:11)
    at assertSyncTransformer (/Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/@jest/transform/build/ScriptTransformer.js:1098:3)
    at ScriptTransformer.transformSource (/Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/@jest/transform/build/ScriptTransformer.js:611:7)
    at _default (/Users/patrickleet/dev/cloudnativeentrepreneur/funnel/node_modules/@jest/reporters/build/generateEmptyCoverage.js:143:38)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)

This error is just for show though - doesn't actually break anything