feat(webpack-preprocessor): Allow specifying typescript path

[chrisbreiding]

• Closes TS error: Option 'sourceMap' cannot be specified with option 'inlineSourceMap' #8477

• Addresses TR-450

• Addresses TR-398

User facing changelog

• Webpack preprocessor now allows passing the path to TypeScript via the typescript option.

Additional details

When we run the default preprocessor and require typescript, it ends up requiring cypress's own version of typescript and not the user's. This prevents us from monkey-patching the correct version of typescript for source maps compatibility.

We already search out the path to the user's typescript and pass it to the preprocessor. This utilizes that path to require typescript.

PR Tasks

• Have tests been added/updated?
• N/A Has the original issue or this PR been tagged with a release in ZenHub?
• N/A Has a PR for user-facing changes been opened in cypress-documentation?
• N/A Have API changes been updated in the type definitions?
• N/A Have new configuration options been added to the cypress.schema.json?

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[cypress]

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Test summary

8746 • 0 • 118 • 3 • 1

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Run details

Project	cypress
Status	Passed
Commit	d26ee43
Started	Nov 24, 2020 8:13 PM
Ended	Nov 24, 2020 8:24 PM
Duration	11:03 💡
OS	Linux Debian - 10.5
Browser	Multiple

View run in Cypress Dashboard ➡️

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Flakiness

	cypress/integration/retries.ui.spec.js		1
1	runner/cypress retries.ui.spec > opens attempt on each attempt failure for the screenshot, and closes after test passes

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[jennifer-shehane]

I verified that this fixes the original issue.

I thought this might have fixed some other weird ts issues:

• 5.4.0 Regression: TypeError: TsconfigPaths.loadConfig if not a function #9326 This issue now throws TypeError: webpack is not a function which I think is the error it should have been initially throwing, meaning it's a duplicate of 5.2.0 Regression: "TypeError: webpack is not a function" when baseUrl present in tsconfig.json #9145 afterall.

[flotwig]

lgtm

[flotwig]

dang it, how else am i supposed to read comments in my 40x12 terminal 😠