Infer project references from common monorepo patterns / tools

Genesis: see section "Repetitive configuration" in https://github.com/Microsoft/TypeScript/issues/3469#issuecomment-400439520

Search Terms

monorepo infer project references automatically yarn lerna workspace package.json

Suggestion

For common monorepo managers, we should natively understand cross-project references declared in package.json as if they were declared in tsconfig.json

Open questions:

• Which formats (lerna, yarn, pnpm, etc) would be supported? Can all of them be consistently detected, or would you need to opt in to a specific "monorepo format" to enable a specific resolution algorithm?
• How do we find the tsconfig.json file? This data is actually not present in the current (non-tsconfig) dependency graph. We could assume it to be in the package root; what if it's elsewhere?
• Would you need to opt in? Would there be a way to opt out? What should that look like?

Use Cases

• Monorepos of all (supportable) flavors

Examples

https://github.com/RyanCavanaugh/learn-a

This repo has a fair bit of duplication where projects need to write down their dependencies in package.json and as references (with different syntax) in tsconfig.json.

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript / JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. new expression-level syntax)

Beginne damit, die im Issue vorgeschlagene Beziehung zwischen package.json und tsconfig.json project references zu lesen, und untersuche anschließend das verknüpfte learn-a-Beispiel. Vergleiche die in den offenen Fragen genannten Monorepo-Formate, einschließlich lerna, yarn und pnpm, und ermittle, wie die Speicherorte von tsconfig.json und das Opt-in-Verhalten funktionieren sollten. Als abgeschlossen gilt ein festgelegtes Design und ein festgelegter Implementierungsumfang für das konsistente Ermitteln von References.