[heft] [rig] project field in typescript.json not working.

[ApolloTang]

Summary

According to https://github.com/microsoft/rushstack/issues/2258#issuecomment-895595035

Added "project" option in typescript.json with identical semantics to the tsc --project parameter

However, when a heft project is rigged, in rig's configuration, it is unclear which tscconfig.json the configuration is read from, and the result is in effect that the typescript task being disabled as described in https://github.com/microsoft/rushstack/issues/2258#issuecomment-895595035:

Using the "project" option in typescript.json introduced in #2844, you can set it to a non-existent file and that will disable the plugin execution.

Repro steps

Set up a rigged heft project and specify a custom tsconfig.json in the project field. See example repo:

https://github.com/ApolloTang/study--rush--node-app/blob/main/02b-node-apps-w-rig--typescript-json-project/tools/heft-node-rig/profiles/default/config/typescript.json#L15

Expected result:

Expect the specified tsconfig.json to be adopted and the typescript task run.

Actual result:

Typescript task is disabled

Details

Detailed discussion in zulip:

https://rushstack.zulipchat.com/#narrow/stream/262522-heft/topic/.E2.9C.94.20.5Brig.5D.20file.20path.20for.20project.20field.20in.20typescript.2Ejson

Standard questions

Please answer these questions to help us investigate your issue more quickly:

Question	Answer
@rushstack/heft version?	0.37.0
Operating system?	Mac
Would you consider contributing a PR?	Not right now
Node.js version (node -v)?	v14.17.3

[ApolloTang]

https://github.com/ApolloTang/study--rush--node-app/blob/main/02d-node-apps-w-rig--turn-on-buildProjectReferences/tools/heft-node-rig/profiles/default/config/typescript.json#L20

Above is my attempt setting the flag:

"buildProjectReferences": true,

as seen in: https://github.com/microsoft/rushstack/blob/master/build-tests/heft-typescript-composite-test/config/typescript.json#L15

But to no avail :(

[iclanton]

There may be an option missing here. By default, this should resolve relative to the root of the project being built (see here).

I'll mess around with your repro.

[iclanton]

So what's happening is the "project" field in typescript.json resolves relative to the project root, so it's looking for a file under /apps/app--node-1/tsconfig.heft.json. If you change the "project" field's value to "node_modules/@myscope/heft-node-rig/profiles/default/config/tsconfig.heft.json", you'll get your expected behavior.

I guess this begs the question: what is the expected behavior here? Would a different resolution be more intuitive? @octogonz @dmichon-msft, thoughts on this?