fix(testing): prevent find from throwing error when query has no match

[tanner-reits]

What is the current behavior?

An error will get thrown when using page.find() for Puppeteer e2e tests if a query returns no elements.

Fixes: #5639

What is the new behavior?

This commit fixes an issue w/ our Puppeteer testing implementation where the find() method would throw an error if the query had no matching elements.

We do not need to make any changes to findAll since the logic there will only attempt to use any returned handles if they exist in an array. Otherwise, no entries will be pushed to the returned array so the result will be an empty array as expected.

Documentation

Does this introduce a breaking change?

• Yes
• No

Testing

Tested changes in the linked issue reproduction case.

Also added tests to our e2e suite so we can avoid regressions related to these functions moving forward.

Other information

[github-actions]

--strictNullChecks error report

Typechecking with --strictNullChecks resulted in 1137 errors on this branch.

That's 1 fewer than on main! 🎉🎉🎉

reports and statistics

Our most error-prone files

Path	Error Count
src/dev-server/index.ts	37
src/dev-server/server-process.ts	32
src/compiler/prerender/prerender-main.ts	22
src/runtime/client-hydrate.ts	20
src/testing/puppeteer/puppeteer-element.ts	20
src/screenshot/connector-base.ts	19
src/runtime/vdom/vdom-render.ts	17
src/dev-server/request-handler.ts	15
src/compiler/prerender/prerender-optimize.ts	14
src/compiler/sys/stencil-sys.ts	14
src/sys/node/node-sys.ts	14
src/compiler/prerender/prerender-queue.ts	13
src/compiler/sys/in-memory-fs.ts	13
src/runtime/connected-callback.ts	13
src/runtime/set-value.ts	13
src/compiler/output-targets/output-www.ts	12
src/compiler/transformers/test/parse-vdom.spec.ts	12
src/compiler/transformers/transform-utils.ts	12
src/compiler/transpile/transpile-module.ts	12
src/mock-doc/test/attribute.spec.ts	12

Our most common errors

Typescript Error Code	Count
TS2322	361
TS2345	344
TS18048	204
TS18047	82
TS2722	37
TS2532	24
TS2531	21
TS2454	14
TS2790	11
TS2352	9
TS2769	8
TS2538	8
TS2416	7
TS2493	3
TS18046	2
TS2684	1
TS2430	1

Unused exports report

There are 14 unused exports on this PR. That's the same number of errors on main, so at least we're not creating new ones!

Unused exports

File	Line	Identifier
src/runtime/bootstrap-lazy.ts	21	setNonce
src/screenshot/screenshot-fs.ts	18	readScreenshotData
src/testing/testing-utils.ts	198	withSilentWarn
src/utils/index.ts	145	CUSTOM
src/utils/index.ts	269	normalize
src/utils/index.ts	7	escapeRegExpSpecialCharacters
src/compiler/app-core/app-data.ts	25	BUILD
src/compiler/app-core/app-data.ts	115	Env
src/compiler/app-core/app-data.ts	117	NAMESPACE
src/compiler/fs-watch/fs-watch-rebuild.ts	123	updateCacheFromRebuild
src/compiler/types/validate-primary-package-output-target.ts	61	satisfies
src/compiler/types/validate-primary-package-output-target.ts	61	Record
src/testing/puppeteer/puppeteer-declarations.ts	485	WaitForEventOptions
src/compiler/sys/fetch/write-fetch-success.ts	7	writeFetchSuccessSync

[github-actions]

PR built and packed!

Download the tarball here: https://github.com/ionic-team/stencil/actions/runs/8617541404/artifacts/1398111439

If your browser saves files to ~/Downloads you can install it like so:

unzip -d ~/Downloads ~/Downloads/stencil-core-4.15.0-dev.1712673241.a888a7c.tgz.zip && npm install ~/Downloads/stencil-core-4.15.0-dev.1712673241.a888a7c.tgz

[rwaskiewicz]

All in all looks good! I have an ask for an additional test suite with a non-encapsulated component, but nothing too serious. LMK if you have any questions

[rwaskiewicz]

Can we add a similar component (and matching suite of tests) where it doesn't use shadow? I don't think it matters if it's totally non-encapsulated or used scoped - I just want to make sure that in the case there's not an actual shadow root, we handle that case as well.

[kensodemann]

I have also tested this PR using the Esri sample project and it passes there without issue.