fix(testing): perform string -> boolean type coercion for Jest config

[alicewriteswrongs]

This adds some manual string -> boolean type coercion to the code that we use to convert CLI flags to a Jest config (after parsing them with yargs).

This fixes an issue documented in #5640 where boolean CLI flags like --watchAll were being passed to Jest as strings, instead of as booleans, so that it was not possible to disable a flag by doing --flagName=false (the value of the flag would be set to the string "false" which is a truthy value).

We previously did this only for a few special-cased things, like so:

stencil/src/testing/jest/jest-27-and-under/jest-config.ts

Lines 84 to 86 in 2082368

	if (typeof jestArgv.ci === 'string') {
	jestArgv.ci = jestArgv.ci === 'true' || jestArgv.ci === '';
	}

There was also a somewhat related issue with not properly parsing boolean flags in our CLI parser which was recently fixed in #5646.

fixes #5640
STENCIL-1259

What is the current behavior?

We don't properly coerce strings like 'true', 'false' to booleans when constructing Jest CLI arguments. This results in a situation where if you pass something like --watchAll=false you'll actually end up running tests in watch mode, which isn't what you want!

This fixes that behavior by explicitly coercing strings to booleans when they're in our list of defined boolean CLI flags.

Does this introduce a breaking change?

• Yes
• No

Testing

First I think it's good to confirm you can reproduce the error.

Basically, start a test project w/ @stencil/core@latest installed and do

npx stencil test --spec -- --watchAll=false

you should observe that this starts things in watch mode, contrary to what you might expect.

then build, pack, and install this branch in the same project and run the same command. It should now run the tests without starting watch mode.

[github-actions]

PR built and packed!

Download the tarball here: https://github.com/ionic-team/stencil/actions/runs/8785317808/artifacts/1435751495

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

unzip -d ~/Downloads ~/Downloads/stencil-core-4.16.0-dev.1713794235.0fa4e4a.tgz.zip && npm install ~/Downloads/stencil-core-4.16.0-dev.1713794235.0fa4e4a.tgz

[github-actions]

--strictNullChecks error report

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

That's the same number of errors on main, so at least we're not creating new ones!

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

[rwaskiewicz]

The functionality here LGTM - one question/comment regarding changing the build infra here and why we need to do it as a part of this PR

[rwaskiewicz]

One non-blocking ask - #5672 (comment)

[tanner-reits]

One quick question

[christian-bromann]

Released in Stencil ♨️ v4.17.0