[REQUIRED] Environment info

firebase-tools:
8.2.0

Platform:
macOS

Node:
10.16.0

Yarn:
2.0.0-rc.33

[REQUIRED] Test case

When generating, installing and running a fresh Typescript version of a functions project using the firebase-tools CLI tool and Yarn 2, 20 errors are produced when executing yarn serve - 3 unique:

Cannot find module 'express-serve-static-core'.
Cannot find type definition file for 'node'.
'functions' is declared but its value is never read.

I can resolve these in the following way, but the resolution causes other errors which are not curable:

1. yarn add @types/node -D
2. yarn add @types/express-serve-static-core -D
3. Modify src/index.ts to export the helloWorld function present in the comments.

This causes the following CLI output:

i  Starting emulators: ["functions"]
✔  functions: Emulator started at http://localhost:5001
i  functions: Watching "/Users/craig/dev/sandbox/firebase-functions-yarn-2" for Cloud Functions...
⚠  Error: Cannot find module '/Users/craig/dev/sandbox/firebase-functions-yarn-2/.yarn/cache/firebase-admin-npm-8.11.0-40c4d739ef-3.zip/node_modules/firebase-admin/package.json'
Require stack:
- /usr/local/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js
Require stack:
- /usr/local/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:957:15)
    at Function.module_1.Module._resolveFilename (/Users/craig/dev/sandbox/firebase-functions-yarn-2/.pnp.js:12283:54)
    at Module._load (internal/modules/cjs/loader.js:840:27)
    at Function.module_1.Module._load (/Users/craig/dev/sandbox/firebase-functions-yarn-2/.pnp.js:12160:36)
    at Module.require (internal/modules/cjs/loader.js:1019:19)
    at require (internal/modules/cjs/helpers.js:77:18)
    at /usr/local/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js:123:32
    at Generator.next (<anonymous>)
    at fulfilled (/usr/local/lib/node_modules/firebase-tools/lib/emulator/functionsEmulatorRuntime.js:4:58)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)
⚠  Your function was killed because it raised an unhandled error.

I can confirm that the zip file '/Users/craig/dev/sandbox/firebase-functions-yarn-2/.yarn/cache/firebase-admin-npm-8.11.0-40c4d739ef-3.zip' contains the path 'node_modules/firebase-admin/package.json'.

I tried downgrading to firebase-tools v8.0.3 as per this issue to no avail.

I tried upgrading Yarn to use the latest sources version to no avail.

I tried using a newer version of Node (v12.16.3) to no avail.

I tried using a newer version of tslint (v6.1.2) to no avail.

Could be an issue with the PnP resolver (https://classic.yarnpkg.com/en/docs/pnp/troubleshooting)? Although I tried running the emulator using the following command, and the error still prevailed.

NODE_OPTIONS="--require ./.pnp.js" firebase emulators:start --only functions

I've created a repository containing the generated project so it's as minimal as possible: https://bitbucket.org/cjmyles/firebase-functions-yarn-2/src. I've included firebase-debug.log as well as the Yarn 2 Zero Install files.

[REQUIRED] Steps to reproduce

1. Install Yarn 2.
2. Execute firebase init functions from the CLI - choose a Firebase project; Typescript (Y); TSLint (Y); install dependencies (N).
3. Execute yarn to install dependencies.
4. Execute yarn serve to see the first set of errors.

[REQUIRED] Expected behavior

Generated project should execute without issues, same as if the project's dependencies were installed and the project executed using Yarn 1.

[REQUIRED] Actual behavior

See test case above.