Add per-package coverage reporting [work-in-progress]

[kevinbarabash]

Summary:

Flow had a command to generate coverage reports for a whole project, but TS doesn't have this capability. There is a third party package called typescript-coverage-report that provides this capability. I added a npm script "type:coverage" that can be used to produce type coverage reports for an individual package. For some reason it doesn't work with the base tsconfig.json.

Issue: None

TODO:

• try to figure out the issue with the root tsconfig.json
• experiment with the "historyFile" setting described in https://github.com/plantain-00/type-coverage#config-in-packagejson

Test plan:

• $PKG=perseus yarn type:coverage
• see that it prints the report in the terminal
• open ts-coverage/index.html to see an HTML version of the repo

[changeset-bot]

🦋 Changeset detected

Latest commit: 4a45229

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 0 packages

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[khan-actions-bot]

Gerald

Required Reviewers

• @Khan/perseus for changes to .gitignore, package.json, yarn.lock, .changeset/afraid-timers-juggle.md

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[github-actions]

Size Change: 0 B

Total Size: 652 kB

ℹ️ View Unchanged

Filename	Size
packages/kas/dist/es/index.js	38 kB
packages/kmath/dist/es/index.js	4.13 kB
packages/math-input/dist/es/index.js	60.3 kB
packages/perseus-editor/dist/es/index.js	114 kB
packages/perseus-error/dist/es/index.js	705 B
packages/perseus-linter/dist/es/index.js	21.2 kB
packages/perseus/dist/es/index.js	398 kB
packages/pure-markdown/dist/es/index.js	3.65 kB
packages/simple-markdown/dist/es/index.js	12.6 kB

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[github-actions]

npm Snapshot: Published

🎉 Good news!! We've packaged up the latest commit from this PR (c6e8014) and published it to npm. You
can install it using the tag PR465.

Example:

yarn add @khanacademy/perseus@PR465

[coveralls]

Coverage: 42.994% (-0.003%) from 42.997% when pulling 4a45229 on type-cov-report into 22c5d56 on main.

[kevinbarabash]

This is superseded by #505.