[Bug?]: Unknown file extension ".json" in the PNP Loader (ESM, Import Assertions)

[samuelexferri]

Self-service

• I'd be willing to implement a fix

Describe the bug

I'm using Node v18 with ESM and --experimental-json-modules flag active in order to use the import assertion for JSON files like this:

import genericERC20 from '../json/FILE.json' assert {type: "json"};

With Yarn v3.2.2 (Zero Install, PNP) I get this error:

Error: Unknown file extension ".json" for /Users/samuelexferri/GITHUB/PROJECT/dist/json/FILE.json

Solutions?

To reproduce

I'm trying to import into a .ts file a json file using Node v18 and --experimental-json-modules flag like this:

import genericERC20 from '../abi/GenericERC20.json' assert {type: "json"};

But when I try to run the script, I obtain this error:

You have triggered an unhandledRejection, you may have forgotten to catch a Promise rejection:
Error: Unknown file extension ".json" for /Users/samuelexferri/GITHUB/PROJECT/dist/json/FILE.json
    at getFileFormat (file:///Users/samuelexferri/GITHUB/PROJECT/.pnp.loader.mjs:129:13)
    at load$1 (file:///Users/samuelexferri/GitHub/PROJECT.pnp.loader.mjs:177:18)
    at ESMLoader.load (node:internal/modules/esm/loader:431:26)
    at ESMLoader.moduleProvider (node:internal/modules/esm/loader:350:22)
    at new ModuleJob (node:internal/modules/esm/module_job:66:26)
    at ESMLoader.#createModuleJob (node:internal/modules/esm/loader:369:17)
    at ESMLoader.getModuleJob (node:internal/modules/esm/loader:328:34)
    at ModuleWrap.<anonymous> (node:internal/modules/esm/module_job:82:21)
    at async Promise.all (index 3)
    at link (node:internal/modules/esm/module_job:87:9)

So I cannot import a JSON file through the .pnp.loader.mjs.

I run the script with NO ISSUES (so JSON correctly imported) deleting lines 128:130 of .pnp.loader.mjs but every time I will run yarn install I will need to remove these lines again.

case `.json`: {
    throw new Error(`Unknown file extension ".json" for ${filepath}`);
}

Environment

System:
  OS: macOS 12.4
  CPU: (10) arm64 Apple M1 Pro
Binaries:
  Node: 18.2.0 - /private/var/folders/0n/cdtksrxx2cj3zvnnq066_hvh0000gn/T/xfs-55b42ae9/node
  Yarn: 3.2.2 - /private/var/folders/0n/cdtksrxx2cj3zvnnq066_hvh0000gn/T/xfs-55b42ae9/yarn
  npm: 8.9.0 - ~/.nvm/versions/node/v18.2.0/bin/npm

Additional context

My .yarnrc:

yarnPath: .yarn/releases/yarn-3.2.2.cjs

nodeLinker: pnp

pnpEnableEsmLoader: true

My .tsconfig:

{
  "compilerOptions": {
    "target": "esnext",
    "module": "esnext",
    "moduleResolution": "nodenext",
    "rootDir": "src",
    "outDir": "dist",
    "strict": true,
    "skipLibCheck": true,
    "sourceMap": true,
    "removeComments": true,
    "resolveJsonModule": true,
    "allowSyntheticDefaultImports": true,
    "experimentalDecorators": true,
    "forceConsistentCasingInFileNames": true,
    "typeRoots": [
      /* List of folders to include type definitions from */
      "./types",
      "./node_modules/@types",
      "./src/types"
    ]
  },
  "include": [
    "**/*"
  ],
  "exclude": [
    "node_modules",
    "dist"
  ]
}

[merceyz]

Duplicate of #4245